P01

地上重力下における多種微粒子含有プラズマの構造と運動の観察○盛林高志, 増田理沙, 三重野哲（静岡大），林康明（京都工繊維大）Observation of Structures and Motions in the Plasma with Size-Distributed Fine Particles
under the Ground Gravity○Takashi MORIBAYASHI, Risa MASUDA, Tetsu MIENO (Shizuoka Univ.),
Yasuaki HAYASHI (Kyoto Inst. Technol.)Related with complex systems, fine-particle plasmas have

There is a stable 3D structure, in which particles aremuch attention to scientists and engineers [1,2]. Hence, we

vibrating. The bigger particles tend to accumulate at theare making crystal-like structures by using a high-edge of cloud.

frequency (HF) Ar plasma, and try to analyze structures andmotions of charged particles under the ground gravity.
Schematic of the developed plasma machine is shown in
Fig. 1. In a stainless steel chamber (150 mmφ, 150 mmh), a
100 mmφ disk electrode and a 80 mmφ metal ring are set.
In this experiment, HF argon discharge (100kHz) is
produced at 10~13 Pa by applying HF voltage of about
270~290 Vrms to the mesh electrode with respect to theupper grounded electrode. And the ring was set on thelower electrode to confine fine-particles. The cloud diffuses

Fig.2 The disk-shaped cloud of Si3N4 in the HF Ar plasma.

under the upper electrode.

VRF=280Vrms, IRF=0.2Arms, f=100kHz, p(Ar)=13Pa.
Fig.3 Solid structure (profile) by charged particles in theplasma.

Fig.1 Schematic arrangement of experimental setup.
The particles used are silicon nitride which have diameterof d ≃ 1 μm. They were injected from a dust dropper. A
digital high speed camera and a CCD video camera are

Referencesused to investigate the particle behaviors. Under discharge[1] Y. Hayashi, K. Tachibana, J. Vac. Sci. Technol. A 14(2),voltage Vd= 280 Vrm, discharge current Id= 0.2 Arm and thepressure p(Ar) = 13 Pa, a disk-shaped cloud is generated as

Mar/Apr 1996, 506.
[2] H. Thomas, G.E. Morfill, V. Demmel, Phys. Rev. Lett. 73,

shown in Fig.2. The expanded image is shown in Fig.3.

－62－

1994, 652.

P02
無容器プロセスを用いた(In1-xGax)SbⅢ-Ⅴ族混晶半導体の過冷度と微細構造○河村 忠晴, 永山 勝久（芝浦工大）

Undercooling and Microstructure of (In1-xGax)Sb Ⅲ-ⅤSemiconductor Alloys by using
Containerless Solidification Process○Tadaharu KAWAMURA1 and Katsuhisa NAGAYAMA2
1Graduate Student, Shibaura Institute of Technology
2
Department of Materials Science, Faculty of Engineering, Shibaura Institute of Technology
1. Introduction
Semiconductor alloys was known as a semiconductor material
continuously a various the lattice constant and band gap
depending on the composition ratio, the production of the bulk
in the homogeneous composition was difficult from the effects
of segregation and convection on the gravity. We've reported on
the relationship of crystal growth and the undercooling degreeof InSb and GaSb particles by using the short drop tube process(free fall section 2.5m).
In this study, we have investigated the formation of III-V typesemiconductor and semiconductor alloy was prepared fineparticles by using the drop tube process.
In addition, we have investigated the relationship of theundercooling degree and the crystal growth of III-V typesemiconductor by using electromagnetic levitation process.

2. Experimental(In1-xGax)Sb (x=0,0.1,0.2,0.3,0.4,0.5,1) alloys was set into thequartz nozzle. The alloy in the quartz nozzle was heating andmelting by electromagnetic levitation coil. Free fall tube in thisapparatus was evacuated by turbomolecular pump to highvacuum before filling He 1atm atmosphere. The molten sample
was dropped by He gas pressure from upperside of the quartz
nozzle, and solidified with containerless.
The structure of the solidified sample was examined by X-ray

Fig.1 XRD patterns of (In1-xGax)Sb (x=0,0.4,1)

diffractometer (XRD) using CuK radiation. The microstructureof solidified sample was observed by Field-emission scanningelectron microscope (FE-SEM), in detail.

3. Results and Discussions
Fig.1 shows the X-ray patterns of InSb(a), (In0.6Ga0.4)Sb(b)and GaSb(c) fine particle samples by drop tube solidified. The
diffraction peaks of the ternary samples were observed in the
middle range of the InSb compound phase and GaSb compound
phase.

Fig.2 Relationship of the composition ratio
and lattice constantFig.2 shows the summarizing the result of XRD measurementof (In1-xGax)Sb (x=0,0.1,0.2,0.3,0.4,0.5,1) semiconductor alloys.
The vertical axis was shown the lattice constant and thehorizontal axis was shown x (Ga composition). In this results,
the lattice constant is continuously changed by increases of x.
Fig.3 SEM images of the surface and microstructure of(a)InSb, (b)(In0.6Ga0.4)Sb and (c)GaSb－63－

Fig.3 shows the SEM images of surface and microstructure of
InSb(a), (In0.6Ga0.4)Sb(b) and GaSb(c) fine particle sample.
Binary sample of InSb(a) and GaSb(c) was formed sharp
projection by solidification expansion. The surface morphology
was indicated a lateral growth may be attributed to the low
undercooling solidification.
However, ternary samples of(In1-xGax)Sb were formed alot of sample surface. It was shown the fine surface by dendritic
structure formation may be attributed to the high undercoolingsolidification.
Also, the binary sample was composed of several crystal
grains in the low degree of undercooling sample, especially. On
the other hand, ternary sample was polycrystalline structure foralmost all samples were solidified in the high undercooling.
Fig.4 shows the SEM image of microstructure of the(In0.6Ga0.4)Sb sample. (In0.3Ga0.7)Sb phase crystallized as theprimary crystal and InSb phase crystallized as the second phase.
Also, the grain boundary was formed segregated In.
The composition ratio of the primary phase also continuously
changed with changing the composition ratio of the (In1-xGax)Sb
alloys.

－64－

Fig.4 SEM images of the microstructure of the (In0.6Ga0.4)Sb.

P03
音場浮遊液滴の浮遊安定性に関する基礎的検討○河野健吾，長谷川浩司，大竹浩靖（工学院大），合田篤（筑波大院），阿部豊（筑波大）

Experimental Investigation of Levitation Stability of an Acoustically Levitated Droplet○Kengo KONO, Koji HASEGAWA , Hiroyasu OHTAKE (Kogakuin Univ.)
Atsushi GODA, Yutaka ABE (University of Tsukuba)

1. Introduction
Acoustic levitation method is studied to apply to
manufacturing new materials in the microgravity condition,
fluid transportation in the chemical and medical field1).
However, this method causes the translational motion andinterfacial behavior of droplet arises from that acoustic radiationpressure acting on its surface2). These non-linear behavior bringabout the negative effect on the quality of materials and fluid
manipulation. With the flat type reflector, it is necessary toincrease the sound pressure in the test section in order toimprove the holding force of levitated droplet, thus,translational motion and interfacial behavior are even more
noticeable. Meanwhile, Xie et al.4) numerically investigated andshowed that it can be improved levitation stability and restoring
force on the droplet with concave reflector. However, theexperimental findings about levitation stability and restoring
force with concave reflector is not enough. We have developed
acoustic levitation system including concave reflector andexperimentally investigated translational motion and soundpressure distribution in the test section5).
As mentioned above, it is important to clarify the non-linear
effect and dynamic motion acting on a levitated droplet andachieve the stable fluid manipulation. Purpose of our study is tofind out the generating mechanism of translational motion andinterfacial behavior (atomization) acting on the levitated droplet
and improve the levitation stability of the droplet.

Test sample is pure water. Diameter of droplet d is calculated
by assuming as spheroid. Aspect ratio b/a is derived by the ratioof the major axis b to the minor axis a. The distance between thehorn and reflector is approximately 49 mm. Shutter speed is
4000fps with spatial resolution of 47±1 μm/pixel.
2.2 Geometry of reflector
In this study, we used two different types of reflectors shownin Fig. 1. The flat type and the concave type are R=∞ (below,R∞) and R=36 (below, R36), respectively. Curvature
configuration of the reflector is shown that R≒2λ is the best
configuration to inhibit trans rational motion of the levitateddroplet by Xie et al. 4). In this paper, we investigated the effectof the geometry of the reflector on the behavior of the droplet.

(a) Flat type (R=∞)(b) Concave type (R=36mm)

Fig. 1 Geometry of each reflector

2. Experimental apparatus
2.1 Experimental procedure and conditions
The experimental systems are composed of the test section,
ultrasonic transmission unit and observation unit. First, wetransmit sinusoidal signal using the function generator andamplification it using the power amplifier. Then this is inputtedto the ultrasonic transducer through the power meter and soundwave is generated from the bottom horn and it reflects on the
top reflector. Acoustic standing wave is formed between hornand reflector and the droplet is injected using syringe in manual
operation. Droplet levitates near the node of the acoustic
standing wave. To observe behavior of levitated droplet, werecorded levitated droplet by backlight method using high speed
video camera and processed the obtained image using computerand application.

－65－

Table 1 Experimental conditions
Input frequency [kHz]19.36

Input power [W]

8.9-55.0

Test sample

Water

Tenparature [℃]

25.5±1.3

Humidity [%]68.9±5Equivarent diameter d [mm]0.3-4.7

Aspect ratio [-]1.0-3.2

3. Translational motion of levitated droplet
Fig. 2 is translational motion with each reflector. Horizontal
axis is time, vertical axis is translational amplitude. It is shownthat translational amplitude with R36 is smaller than that with
R∞. It is assumed that R36 changed the sound pressure
distribution acting on the levitated droplet surface due to thegeometric configuration. As a result, it is considered that R36
suppressed the translational amplitude than that with R∞. It isnecessary to measure the acoustic pressure distribution at thetest section in the state of droplet levitating.

○：R∞, P = 38.3 W, d = 3.4 mm●：R36, P = 40.7 W, d = 3.4 mm

Amplitude [mm]

0.4
0.2
0
-0.2
-0.4
0

4. Behavior of atomization of water droplet

1000

Fig. 3 shows the droplet atomization process and image.

2000

3000

Time [ms]Fig. 3(a) is the time series of aspect ratio with the two different
droplets. Horizontal axis is time, vertical axis is aspect ratio.
Both droplets caused the atomization eventually with rapid
deformation of its interface within last 3 ms. Droplet atomized

Fig. 2 Translational motion of droplet with each reflector

at t = 0 ms. Fig. 3(b) is the image of just before the atomization

20

10

0

5. Concluding remarks
In the present study, we experimentally investigated about thegenerating mechanism of translational motion and interfacial
behavior (atomization). The following can be acquired;
1.
2.

0

Fig. 3 Interfacial instability on the levitated water droplet
Danilov, S. and Mironov, M., Breakup of a Droplet in a Highintensity Sound Fields, J. Acoust. Soc. Am., Vol. 92, (1992), 2747.
4)

Xie, W. J. and Wei, B., Dependence of Acoustic Levitation
Capabilities on Geometric Parameters, Physical Review E, Vol.

Sciences, Vol. 110, No.32, (2013), 12549.
2)-5Time [ms](b) Atomization of water droplet (d=1.6mm, t = 0 ms)

3)Foresti, D., Nabavi, M., Klingauf, M., Klingauf, Ferrari, A. andPoulikakos, D., Acoustophoretic contactless transport andhandling of matter in air, proceedings of the National Academy of-10(a) Time series of aspect ratio

It is shown that translational amplitude with R36 is smaller
than that with R∞.
Droplets caused the atomization eventually with rapid
deformation of its interface within last 3 ms and atomized
from the right and left edge of surface. In our study, thecritical aspect ratio is different from previous work3) andalso depends on the droplet size.

References1)●：d = 1.6 mm○：d = 2.6 mm

Aspect ratio [-]of water droplet showed in Fig. 3(a) which its equivalentdiameter is 1.6mm. As shown in red square in the image, theinterfacial deformation was observed and then atomized fromthe right and left edge of surface. In the theoretical investigation
by Danilov et al.3), it is indicated that the critical aspect ratio is
approximately 8.5. However, the critical aspect ratio is different
in our study, and also depends on the droplet size. It isconsidered that the spatial and temporal resolution are notenough yet, and will be required to improve observation system.

66, 026605, (2002), 1.

Foresti, D., Nabavi, M. and Poulikakos, D., On the Acoustic
Levitation Stability Behavior of Spherical and Ellipsoidal

5)Particles, J. Fluid Mech., Vol. 709, (2012), 581.

Hasegawa, K., et.al., Generation Mechanism of Horizontal
Holding Force of an Acoustically Levitated Droplet, Progress inMultiphase Flow Research, Vol. 27, No. 5, (2014), 563.

－66－

P04
非共溶性混合媒体の核沸騰熱伝達特性に関する研究○喜多祥太, 岩田圭介, 新本康久, 大田治彦（九州大学）

Boiling Heat Transfer by Nucleate Boiling of Immiscible Mixtures○Shota KITA, Keisuke IWATA, Yasuhisa SHINMOTO, Haruhiko OHTA (Kyushu Univ.)
1. Introduction

increase the power of heaters corresponding to a heat flux of

By the development of electronic technology, the heatgeneration density from semiconductors is increasing. It holds
true for the space electronic devices in near future. Liquid
cooling systems utilizing the latent heat transportation by
nucleate boiling heat transfer have more advantages than thecooling by single-phase liquid.
In pool boiling experiments, an optimized combination of
two components with different saturation temperatures andliquid densities improves heat transfer characteristics 1). For
example, critical heat flux(CHF) values for FC72/Water at near
optimized layer thicknesses of FC72 before heating are far
higher than that for pure water under the same system pressure
because of high subcooling condition of water resulted from thecompression effect by the high vapor partial pressure of FC72.
In addition, the surface temperature in the high heat flux regime
is clearly reduced from the pure water. Furthermore, in thepresence of the fluctuation of thermal load for practical coolingsystems like automobiles, the stability of surface temperature is
improved because FC72 accumulated on the heating surface isused at the boiling incipience. This paper reports newexperimental data of boiling heat transfer by using immiscible
mixtures.

4.5106 W/m2. In the block, thermocouples are inserted at
different depths to evaluate the heat flux and the temperature on
the heating surface. Heat transfer coefficients are evaluated byusing the temperature of bulk liquid. The heat flux just before
the value accompanied by the temperature excursion is regarded
as CHF.

3. Characteristics of immiscible mixtures120

FC72/Water
P = 0.1MPa

Bubble point curve
Dew point curve

Tsat C

100

80

60

40
0

Fig.2

0.2
0.4
0.6
0.8
Weight fraction of FC72

1

Phase equilibrium diagram

The vapor-phase and liquid-phase for each component are kept
at the thermal equilibrium state under the system pressure,
where the summation of saturated vapor pressures of thecomponents at the equilibrium temperature becomes the totalpressure. Figure 2 shows the phase equilibrium diagrams for
FC72/Water at the total pressure of 0.1MPa. Higher saturated
vapor pressure of more-volatile component compresses the lessvolatile liquid above its saturation pressure corresponding to the

2. Experimental apparatus

equilibrium temperature, e.g. equilibrium temperature is 51.6C,

Fig.1

Experimental apparatus

The experimental apparatus is composed of a boiling vessel,
condensers and a heating block assembly as shown in Fig.1. In
the heating block assembly, the upper edge of the cylindricalcopper block is operated as a heating surface which has ahorizontal circular area with a diameter of 40mm facing
upwards. The block is heated by the cartridge heaters inserted in
the bottom. The design of the heating block is changed toand higher subcooling 48.4K is given to the less-volatile liquid,water. On the other hand, the more-volatile liquid is compressedby the lower partial pressure of less-volatile component, andlower subcooling 4.3K is given to FC72. As a consequence,
self-sustaining subcooling is given for immiscible liquids evenunder the pool boiling conditions.

4. Experimental results
4.1 Heat flux versus temperature difference and heating
surface temperature
Figure 3 shows the relation between the heat flux q and

－67－

107

FC72/Water

cylindrical heating block is caused by the falling condensate
droplets of more-volatile liquid with higher density in addition
to the natural circulation in the vessel. As a consequence, a partof FC72 is carried on the heating surface, and the heat transfer
characteristics at high heat flux become similar to those for[5mm/95mm]. Decreased heating surface temperature for
FC72/Water [5mm/95mm] and [0mm/100mm] than pure water
is observed by the aid of vaporized FC72 as shown in Fig.4.

P = 0.1MPa

Water
FC72

q W/m2

106

105
FC72/Water [0mm/100mm]
FC72/Water [5mm/95mm]
FC72/Water [10mm/90mm]
FC72/Water [50mm/50mm]

104 0
10

101

102

103

Tsat , Tb K
Boiling characteristics

Fig.3
107

4.2 Critical heat flux
The values of CHF accompanied by the surface temperature
excursion are represented by the horizontal dotted lines in Figs.
3-4. The actual CHF values for the mixtures at FC72/Water[0mm/100mm] and [5mm/95mm] were not measured restrictedby the available capacity of condensers. For FC72/Water[0mm/100mm], the maximum value of the heat flux measured
becomes 2.85106W/m2, i.e. 2.2 times higher than CHF for pure

FC72/Water

water under the same pressure. The CHF value for FC72/water
predicted by Ivey-Morris correlation 2) corresponding to theself-sustaining subcooling ΔTsub =48.4K becomes as much as
4.3×106 W/m2, far larger than the value for pure water. Such a
drastic increase of CHF could be expected provided that thelarge layer thickness of more-volatile liquid does not disturb thechange of liquid contacting the heating surface by intermediate
burnout. The verification of larger CHF than obtained so far isscheduled by the improvement of cooling capacity of the boiling
vessel.

P = 0.1MPa

Water
FC72

q W/m2

106

105

104

Fig.4

FC72/Water [0mm/100mm]
FC72/Water [5mm/95mm]
FC72/Water [10mm/90mm]
FC72/Water [50mm/50mm]

60

80

100

120
Tw C

140

160

180

5. Conclusions

Heat flux versus heating surface temperaturetemperature difference for FC72/Water. In the abscissa, thetemperature difference ΔTb between the heating surface and theequilibrium liquid temperature is used for the mixture at thesubcooled state, while it is substituted by the surface superheat
ΔTsat for pure components at the saturation state under the same
total pressure. In the case of small thickness for FC72 layer, i.e.
FC72/Water [10mm/90mm] and [5mm/95mm], the local
burnout and the small temperature excursion occur at the heat
flux of around 2105 [W/m2] which is lower than that of pure
FC72 and [50mm/50mm]. The reduction of CHF is deduced tobe due to the shortage of FC72 supply for such small initiallayer thicknesses. Authors named this temperature jump as“intermediate burnout”. For a large thickness, i.e. FC72/water[50mm/50mm], the curve almost coincides with that for pure
FC72 at the saturation state because of small subcooling of
FC72 for the mixture. On the other hand, FC72 for[0mm/100mm] is filled only around the cylindrical heating
block without the layer on the heating surface at least before theheating. The disturbance at the liquid-liquid interface around theLarger CHF values than that for pure water are obtained under
the high subcooling condition resulted from the compression
effect by the high vapor partial pressure of more volatilecomponent. Moreover, in the less volatile dominated regime at
the heat flux larger than that for intermediate burnout, theheating surface temperature is lower than that for pure lessvolatile component at the same total pressure. By these features,
the boiling of immiscible mixtures has a great potential for thehigh-performance cooling systems for space or groundapplications.

References
1)

2)

－68－

H. Kobayashi, N. Ohtani and H. Ohta: Proc. 9th International
Conference on Heat Transfer, Fluid Mechanics andThermodynamics, (2012) 771
H. J. Ivey and D. J. Morris: Proc. Third International Heat
Transfer Conference, 3 (1966) 129

P05
ISS における InGaSb 結晶成長実験に対する数値シミュレーション○ ミルサンディ ハルヨ，山本卓也，高木洋平，岡野泰則（大阪大），稲富祐光（JAXA），
早川泰弘（静岡大）Numerical Simulation of InGaSb Crystal Growth Experiment on the ISS○ Haryo MIRSANDI, Takuya YAMAMOTO, Youhei TAKAGI, Yasunori OKANO (Osaka Univ.),
Yuko INATOMI (JAXA), Yasuhiro HAYAKAWA (Shizuoka Univ.)
1. Introduction

3. Results and Discussion

InGaSb ternary alloy semiconductor is a highly promisingmaterial for thermo-photo-voltaic devices. However, it isdifficult to grow high quality homogeneous InGaSb crystals on
Earth due to gravitational segregation occurring during growth.
This adverse effect is minimized in the microgravity
environment due to the absence of strong natural convection.
InGaSb crystal growth experiments are being conducted using a
GaSb/InSb/GaSb-sandwich system onboard the International
Space Station (ISS) to investigate the effects of gravity and tounderstand interface kinetics during the growth process1). In thepresent study, the crystal growth process was numericallysimulated in order to shed lights on the transport phenomena
occurring in the solution of this sandwich system.

Fig. 2 shows the time evolution of the center position of theseed/solution interface. The interface position of theseed/solution moved down first and then moved up slowly
indicating that the crystal grew after the dissolution of GaSb
seed crystal. In case of higher heating rate, at 3 min. of theprocess under 1 G, the solution reached supersaturation and thegrowth started. However, under 10-4 G, growth started at 5 min.
It is because under 10-4 G, mixing in the solution became weak
due to the suppression of solutal convection. Moreover, sinceconvection enhances the upward transportation of GaSb solutenear the seed/solution interface, the dissolution length of seed

2. Numerical Method
The numerical model is two-dimensional and axisymmetric.
The computational domain consists of the InGaSb solution, theGaSb solid crystals, and the crucible ampoule wall (Fig. 1). The
governing equations in the liquid phase are the continuity,
Navier-Stokes, energy, and diffusion equations. In the solid
phases, the governing equation is the energy equation. The massand heat balance equations are solved at the crystal/solution
interface for considering the dissolution and growth of thecrystal. Numerical simulations were carried out under both 1 G
and microgravity level of 10-4 G that corresponds to the averagegravity level observed on the ISS for comparison. Two values ofheating rate were used: 10 °C/s and 0.06 °C/s (Table 1).
Label
Case A-1
Case A-2
Case B-1
Case B-2(a)Table 1 Numerical conditions
Heating rate (°C/s)
Gravity level (G)
10
1
10
10-4
0.06
1
0.06
10-4
(b)

under 1 G was longer than that of under 10-4 G (Fig. 3). In caseof lower heating rate, growth started almost at the same time andthe dissolution lengths of seed crystals were almost the sameunder both gravity levels. This is due to the fact that in the caseof lower heating rate, concentration gradient in the solution was
low; as a result the solutal convection was suppressed evenunder 1 G conditions.

Fig. 2 Time evolution of the center position of the seed/solution
interface.

Fig. 3 Time evolution of dissolution length.

References
Fig. 1 (a) Ampoule configuration and (b) an ambient
temperature profile.

1)

M. Nobeoka, Y. Takagi, Y. Okano, Y. Hayakawa, and S. Dost: J.
Crystal Growth, 385 (2014) 66.

－69－

P06
超音波浮遊液滴の内外部流動と伝熱特性○丹羽基能，合田篤（筑波大），長谷川浩司（工学院大），金川哲也，金子暁子，阿部豊（筑波大）

Flow Behavior and Heat Transfer Characteristics of an Ultrasonically Levitated Droplet○Motonori NIWA, Atsushi GODA (Univ. of Tsukuba), Koji HASEGAWA (Kogakuin Univ.),
Tetsuya KANAGAWA, Akiko KANEKO, Yutaka ABE (Univ. of Tsukuba)
1. Introduction
The container-less processing using levitation techniques canprevent the heterogeneous nucleation and the contamination due
to the container wall. It is expected to be used in analyticalchemistry and production of new materials under microgravity
environment. In addition, laser heating to a droplet is expected
to be used in condensation of solution. An acoustic levitation is
one of the levitation techniques, and induces the internal flow 1)
and external flow which are dependent on volatility 2). However,there are few experiments which evaluate the heat transfer
performance of acoustically levitated droplets. This paper
discusses the relationship between the heat transfer and flow
characteristics of acoustically levitated droplets with
evaporation and on laser heating.

levitated droplet is substantially higher than that estimated by
the well-known empirical equations of a heat transfer
characteristics around a sphere. It suggests that the complex
external flow enhance the heat transfer characteristics.
Fig. 2 (b) shows the heat transfer characteristics on laser
heating at the upper region of a water droplet. The heat transfer
coefficients are calculated based on the volume change andtemperature rise of droplets. We can confirm that Nusselt
number, Nu, increases significantly. It is implied that theevaporation is induced intensively by laser heating and thisenhances the heat transfer characteristics. Thus, the heat transfer
characteristics on laser heating become more effective than thatwith evaporation.

2. Experiments
The experimental setup consists of a single axis acousticallylevitator and measuring devices. The droplets are generated at
the pressure node of the standing wave using a syringe. The sizeof droplets is millimeter-scale, and the shape of droplets is anellipse. Three types of fluids are used: water, 50wt % aqueous
solution of ethanol, and ethanol. The levitated droplet isvisualized by a high speed camera in order to obtain velocity
vector fields by PIV and observe the volume change. The
temperature gradient near the surface and the surface
temperature are measured by a thermocouple and an IR camera,
respectively. In the case of heating, the upper part of a water
droplet is heated by a 1.5 W YAG laser.

(a) Internal flow
Fig. 1(b) External flow

Internal and external flows of a water droplet

(a)

(b)

2.1 Internal and external flows of a levitated droplet
Fig. 1 (a) and (b) represent velocity vector fields of theinternal and external flows of a non-heated water droplet,
respectively. The internal flow rotates around the center of thedroplet as a stagnation point (Fig. 1 (a)). On the other hand, theambient air around a water droplet streams from both side
regions toward the upper and lower regions. In addition,

Fig. 2

toroidal vortices are observed at the bottom of the droplet (Fig.

evaporation and (b) water droplets on laser heating

1 (b)).
2.2 Heat transfer characteristics of a levitated droplet
Fig. 2 (a) shows the heat transfer characteristics with
evaporation. The heat transfer coefficient is estimated from thevolume change and the temperature gradient near the droplet
surface. From this result, the heat transfer of the acousticallyHeat transfer characteristics of (a) droplets with

References
1)

Y. Yamamoto, Y. Abe, A. Fujiwara, K. Hasegawa and K. Aoki:
Microgravity Sci. Technol., 20 (2008) 277.

2)

－70－

K. Shitanishi, Y. Abe and A. Kaneko: Japanese J. Multiphase
Flow, 26 (2013) 537.

P07
超音波浮遊液滴の界面近傍微小スケールにおける流動挙動と輸送現象○合田篤（筑波大院），長谷川浩司（工学院大），金川哲也，金子暁子，阿部豊（筑波大）

Flow Behavior and Transport Phenomena in Vicinity of Interface
around Ultrasonically Levitated Droplet○Atsushi GODA(University of Tsukuba), Koji HASEGAWA (Kogakuin University), Tetsuya KANAGAWA,
Akiko KANEKO, Yutaka ABE (University of Tsukuba)
1. Introduction
By using levitation techniques, the method called thecontainer-less processing can remove influences of walls. An
acoustic levitation is applicable to any objects. There are various
practical studies: the separation of the mixed fluid by using
evaporation behavior1), and the contact-less mixing2), and so on.
On the other hand, an acoustically levitated droplet induces
internal and external unsteady flows with nonlinearity. It is
important to investigate the interaction of such a behavior andthe phase-change process. Our group reported that the flow
structure was different between with and without evaporation3).
However, the cause of the flow generated around the levitateddroplet with evaporation is unclear. In addition, it is importantto understand heat transfer from the levitated droplet in actual
application of the acoustic levitation method. The purpose ofthis study is to clarify the interaction between the flow behavior
and transport phenomena around an acoustically levitateddroplet. Hence, we measured the external flow, and volume andsurface temperature of the levitated droplet, and evaluated theflow structure and heat transfer.

correlation. In the droplet with the circular vortex such as
ethanol solution of 50, 75 and 100 [wt%]5), the heat transfer
coefficient is larger than that estimated from Ranz-Marshal
correlation. This result suggested that the heat transfer
coefficient have been affected by the complex flow structurearound the droplet.

Water

Non-volatility 5.24 [mm]Fig. 1

HexaneEthanol

Volatility 5.24 [mm]Volatility 5.24 [mm]

The Flow trajectory of the external flow

Ua=300 [mm/s](Water）
Ua=150 [mm/s](Ethanol）

2 Results and discussions
Fig. 1 shows the visualization results of the external flow inthe vicinity of droplet. In the case of water droplet, thesurrounding fluid flows out to the upper and lower of thedroplet. In contrast, in the case of the volatile droplet, thesurrounding fluid flows from the upper and lower of the droplet.
In addition, the circular vortices were observed in the vicinity ofthe volatile droplet. In addition, this result suggested that thesize of circular vortex decrease with the increasing in thesaturated vapor pressure.
To calculate the heat transfer coefficient from the time serieschange of the droplet volume, we assume that all the amount ofheat given from the surrounding, are regarded as the latent heatof droplets. Fig. 2 shows the result of heat transfer coefficient,and the curves denoted by estimated from Ranz-Marshal
correlation4; the black solid curve represents the condition
without the convection, and the red and blue dashed represent
show the condition with the convection evaluated by thevelocity in the vicinity of droplet. In the ethanol solution of 25[wt%] and water, the circular vortex was not observed5) and theheat transfer coefficient is the same value as Ranz-Marshall

Ua=0 [mm/s]

Fig. 2 Heat transfer coefficient of levitated droplet,where Ua is the velocity in the vicinity of droplet.

References
1)

S. Santesson, I.B.R. Ramirez, P. Viberg, B. Jergil, and S. Nilsson:
Analytical Chemistry, 76, 2, 2004, 303.

2)

D. Foresti, M. Nabavi, M. Kingauf, A. Ferrari, and D. Poulikakos:
PNAS, 110, 31, 2013, 12549.

3)

H. Ishii, K. Hasegawa, A. Kaneko, and Y. Abe: Transactions of theJapan Society of Mechanical Engineers, Series B, 78, 794, 2012,
1696.

4)
5)

－71－

W. Ranz and W. Marshall: Chem. Eng. Prog, 48, 4, 1952, 141.
A. Goda, K. Hasegawa, A. Kaneko, and Y. Abe: Proc. Japan.
Symp. Multiphase Flow, A143, 2014.

P08
航空機による微小重力環境を用いた金属液滴と溶融酸化物の濡れ性の観察○小野寺健太，水野章敏，渡邉匡人（学習院大）

Observation of Wettability Between Melting Oxide and Liquid Metal Droplet under
Microgravity Conditions by Parabolic Flight○ Kenta ONODERA, Akitoshi MIZUNO, Masahito WATANABE (Gakushuin Univ.)
1. Introduction
The Oscillating drop technique with surface oscillation
analysis is useful for measurements of thermophysical propertiesof high-temperature liquid by using the levitation technique.
The conventional surface oscillation analysis derives surface
tension and shear viscosity of liquid even on the groundconditions. Recently, modified surface oscillation analysis ofcompound droplets has been tried to measurement theinterfacial tension of immiscible liquid system. However,modified surface oscillation analysis for compound droplets canbe applied only in the microgravity conditions because thedensity difference separates two liquid parts under the ground.
Interfacial tension is important thermophysical properties on theindustrial process control, therefore, we propose themeasurements of interfacial tension between steel melts andmolten oxides using the electrostatic levitation furnace (ELF) in
ISS with modified surface oscillation analysis. For preparationof ISS experiments, we performed parabolic flight experiments
to confirm the formation of compound droplet, core-shell
droplets, using liquid metals and molten oxides using theelectromagnetic levitation method.

is core-shell droplets by two phase separated liquids, must
consider the interaction between core and shell by interfacial
tension. In this system, two normal mode frequencies appear on
the surface of shell liquid by following expression3);

 2  K K 

1  mi mo
2   3

W
J

(2)
2

3 

3 

  1  mi  mo   13 
4  
W 0 2 8
1J (1  i ) 10  2 i

(3)

(4)

3

where

3
2
mi   5   555
mo  (1  i ) 5  i 5
i 3 ( i   o )
.
5
o

(5)

(6)

In the eq.(2),  are normal mode frequencies of the twophases separated droplet.    0 12 and Ro Ri is ratio of

2. Droplet Dynamics

surface tension  0 and interfacial tension  12 , ratio of radius,

2.1 Simple droplet
The conventional surface oscillation technique is a suitable
method for measurement of surface tension using noncontact
technique. It assumes non-viscos droplet oscillates without

respectively. If we obtain  , we know the interfacial tension.

external force. In this case, normal mode frequency 0expresses surface tension  0 by Rayleigh's formula;

02 

8 0
o Ro3(1)

where  o is density of droplet and Ro is radius of droplet.
By replacement to o Ro3  3M 4 , Eq.1 becomes the simple
expression not to depend on the density. Under the gravity, it
must correct the frequency by the expression of Cummings andBlackburn, it is because a sample transforms by gravitational
influence and strong electromagnetic force. On the other hand,in microgravity condition, there is only one normal mode
frequency of the simple droplet.
2.2 Two phases separated droplet
The normal mode frequency of the compound droplet, which

3. Experiment
For the observation normal mode frequencies of compound
droplet, we developed a small electromagnetic levitation furnace(Parabolic Flight Experimental Facilities: PFLEX), which isable to put on board a airplane. The radio frequency current
through the coils levitates the sample by Lorenz force. At thesame time, it heats from joule heat, which caused by induction
current at the sample surface. Using 2color-pyrometer and highspeed recording system (250fps), we obtained droplet
oscillation motion with its temperature. In order to melt oxidematerials, we use the heat conduction from the liquid samples
with Eddy current heating by RF current to the oxide samples.
We used the starting samples of Ag partially covered with solid
B2O3. Using the samples, we observed melting and wetting
phenomena and surface oscillation of droplet from the top viewby the parabolic flight during 20s.

－72－

4. Result and discussion
We success to observe wetting phenomena and surface
oscillation for levitated droplet, which liquid Ag was covered
with melted B2O3. Figure 1 (a) shows levitated droplet on the
ground. On the ground conditions, liquid metal and molten
oxide separates top and bottom like a snowman’s shape. For the
shape of liquid drop, we cannot apply to the formula of eq. (2)(6). Figure1 (b) shows the observation results of liquid Ag
covered by molten B2O3 under the microgravity condition.

(a)(b)
Figure 1 (a)Side view of levitated sample on the ground and(b)top view of levitated sample under microgravity condition.
From the surface oscillation images of liquid Ag covered withmolten B2O3 samples observed from the top view images, we
obtained oscillation frequencies by FFT analysis. Figure2 shows
power spectrum of FFT results, where Area is cross-sectional
area of sample. According as R x is sample radius of x-axis
and R y is its radius of y-axis, we define R  Rx  Ry andR  Rx  Ry , respectively. In the compound droplet oscillation,
there are two peaks of normal mode frequencies, which
considered the fully covered droplet model. However, in thisexperiment, the molten B2O3 fragmented without completely
covering the Ag. The flow of B2O3 fragmented evoked
Marangoni flow on the surface of the liquid Ag. Therefore, it isdifficult to identify some peaks clearly. We discuss looking for apeak by appropriate mode choice carefully. The fragmentation
phenomena of molten B2O3 would be cause by starting sample
conditions. In this experiment, we used spherical Ag samples
partially covered by solid B2O3. If molten oxide fully covers on
liquid metal, we must prepare the samples, which solid oxide
samples fully covers with the metal samples.

Figure 2 Comparative of oscillation frequencies of Ag+B2O3
droplet in microgravity condition.

6. Summary
We succeeded to levitate the compound sample which consistsof Ag and B2O3 and to obtain surface oscillation frequencies.
However, it is difficult to identify peak origins because in thepresent experiments liquid Ag sample partially covered bymolten B2O3. For the future experiments, we prepare thestarting metal samples fully covered by oxides to makecompound droplets with core-shell structure.

References
1)

L. Rayleigh: 29, No.196-199, Proc. R. Soc. London(1879),
pp.71-97.

2)

D.L.Cummings and D.A.Blackburn: J. Fluid. Mech.
(1991), 224, pp.395-416

3)

－73－

M.Saffren, D.D.Elleman and W.K.Rhim: Proc.2nd Int.
Colloq. On Drop and Bubbles(1982), pp.7-14.

P09
パラボリックフライトによる微小重力環境を利用した
柔軟宇宙構造物の軌道上挙動推定法○丸木悠暉，嶋崎信吾，村田亮，宮崎康行（日本大学）

Estimation Method of Dynamic Behavior of Flexible Structure in Space
Using Microgravity Environment by Parabolic Flight○Yuki MARUKI, Shingo SHIMAZAKI , Ryo MURATA , Yasuyuki MIYAZAKI（Nihon University）
1. Background and Objectives
In recent years, the research on flexible large space structureis rapidly advanced in many country. Nihon university haslaunched a nano-satellite named "SPROUT" which
demonstrates a concept of a flexible space structure. The main
mission of SPROUT is deployment of a triangular membrane
combined with inflatable tubes. In order to utilize the results of
the on-orbit demonstration for the realization of flexible large
space structure, it is important to predict the deployment motion
in advance on the ground. There are several prediction methods,
e.g. numerical simulation 1)2)3) and experiment by using thesmall conceptual model 4). In this paper, the author proposes a
new prediction method by the combination of 1G experimentand the microgravity experiment with ambient.

Fig. 3

Experiment frame

Dynamic behavior is recorded by some angle cameras
and position of the three-dimensional coordinates ismeasured by stereovision from many markers on
combined membrane.
3. Estimation Method and Results
Fig. 4 shows Definition of axis.

Fig. 1

Nano-satellite named "SPROUT"

2. Experimental Method
Fig. 2,3 show experiment sample and frame. Combined
membrane is a triangle with each side about 440 mm. Inflatable
tubes is extended by air with 70 kPaG.

Fig. 4

Definition of axis and position vector

In this estimation method, it is assumed that the air density
and the displacement is proportional. X and y axis displacement“d” on estimation is defined by the equation
t i
x do

t i
x dg

t i
xd

g

t i
xd

(1)

Fig. 2t iy do

Sample（combined membrane）

t i
y dg
g

t i
yd

t i
yd

where ρ is the air density, subscript of upper left is time, upper
right is number of node on combined membrane, left lower is－74－

axial direction, and right lower is environment: o is estimation
on orbit, g is 1G experiment, µ is microgravity experiment.
As well, influence of the air density and gravity about z axis
displacement is corrected by the following equation
t i
zd

t i
z dg

t i
zd

t i
zd

g

t

t i
zd

t i
zd

gg

g

g

t i
z do

t
t

t i
yo
t i

y

t i
yo
t i

t

k

t i
zd

Fig. 7(4)

Fig.5 shows estimation of dynamic behavior on orbit byt izd

membrane. Fig.7 shows the experiment condition in
microgravity experiment: atmospheric pressure in theexperiment plane, microgravity signal (Trigger), andacceleration of each axis.

4.40 [sec]6.50 [sec]Fig.5 Results of estimation on orbit

Fig. 6(3)yresults of 1G experiment and microgravity experiment. Fig.6
shows time history displacement of the node of the tip of thewhere g is gravity acceleration. Furthermore, factor of
proportionality k is expressed by the following equation.

2.30 [sec]

t i
y do
t i
yd

Z axis displacement on estimation is expressed by the following
equation.

(2)
t i
z dg

k

Displacement of y axis direction (left) and z axis direction (right)

Atmospheric pressure in plane(left) and gravity level(right)－75－

8.60 [sec]From results of Fig.6(left),7(left), displacement of 1G
experiment is 0.7～0.9 times smaller than that of microgravity
experiment on y axis. And atmospheric pressure in microgravity
experiment plane is about 0.8 times smaller than that in the
1Gexperiment. So assumption that the air density and thedisplacement is proportional has a validity.
From results of Fig.6(right),7(right), acceleration of each axisof microgravity experiment is about 0 G, and displacement ofz axial direction of estimation and microgravity experiment isapproximately equal. Therefore result of estimation of z axial
direction has a validity.

4. Summary
Author experimented about deployment of combine
membrane in 1G environment and microgravity environment.
Also author estimated dynamic behavior on orbit by the
combination of 1G experiment and the microgravity experiment.
In the future, we will conduct 1 G vacuum experiment, andestimate by result of that. Also we will study the similarity
parameters, then, apply them to actual size combined membrane.

By comparing the estimation and results on orbit by SPROUT,
we will study a validity and accuracy of estimation.

References
1)

A. Muta, S. Matsunaga and N. Okuizumi : 52nd The lecture
meeting about strength of structure, Tottori, JSASS, 2010-3015,
2010.

2)

M. Miyazaki, Y. Shirasawa, O. Mori, H. Sawada, et.al., Proc.
52nd SDM, AIAA , 2011-2181, 2011.

3)

M. Yamazaki, A Study on Model Order Reduction for Nonlinear
Structural Dynamics of Membrane Space Structure, 2011.

4)

M. Yanagisawa : Similarity Rules for Spin-Deployable membrane,
2006.

－76－

P10
物理学教育で使用できる無重力下ルーブ・ゴールドバーグマシンの作製○窪田美紀（東京学芸大学大学院），岡本優輝，柿本嵩人，柳瀬綾花，吉永恭平（東京学芸大学）

Rube Goldberg Machines under Zero-Gravity that can be used in Physics Education○Miki KUBOTA, Yuki OKAMOTO, Takahito KAKIMOTO,
Ayaka YANASE, Kyohei YOSHINAGA (Tokyo Gakugei Univ.)
1. Introduction

Also many students answered that they were interested.

Many students have misconceptions in physics. Also many
students feel that “Physics is difficult.” To motivate students inlearning physics, we have developed a Rube Goldberg machinethat shows several simple physics experiments. We ran thismachine under micro-gravity, recorded this machine motion
with video camera, and tested its educational effectiveness.

4. Conclusion
Our Rube Goldberg machine performed expected motion in
microgravity, and we succeeded in video recording. High school
students are interested in our equipment and video, so thismachine is effective in motivating high school students to think
about physics.

2. Equipment
We developed a Rube Goldberg machine that shows threeexperiments in physics. Experiments chosen for this machine
were the motion of pendulum, relations of mass and acceleration,
uniform linear motion. We named the section which showed the
motion of pendulum as section A, relations of mass andacceleration as section B, uniform linear motion as section C.
Details of each experiment is described. (Shown in Fig.1)
2.1 Section A
In the section A, we observed the motion of pendulum during
1g, 2g, and μg. The pendulums were started at 1g, and isobserved during the machine goes through 2g and μg.

Fig.1 Overview of Rube Goldberg Machine
And camera settings
No.1 Section A recording
No.2 Section B recording
No.3 Section C recording
No.4 Section B/C connection recording

2.2 Section B
The section B is responsible for showing relations of mass
and weight. Four arms with different weights are placed so thatmass gradually grows larger. Constant elastic force is given to
those weights. When the stopper is taken off, the observer can
see the behavior of four arms. (Shown in Fig.2)
2.3 Section C
In the section C, we observed uniform linear motion on therail using two iron balls. Two iron balls are equal in mass andsize. These balls are hit at the same time with a lever, and they
start to roll on the rails. There are magnets at the each end of therails, and due to iron balls sticking to the magnets, electric
circuits made of LEDs and motor are completed, and these will
mark the end of this Rube Goldberg machine.

3. Classroom practice
We recorded the behavior of this machine with five digital
video cameras. After editing the data into one video file, we
showed the video to Tokyo Gakugei university senior highschool and Kunitachi Metropolitan high school students to see
if the video motivated students to think about physics, or madethem interested in physics. As a result, students eagerly
discussed about the results, were surprised that these simple
experiments showed unexpected actions under micro-gravity.

Fig.2 Schematic of Rube Goldberg Machine Section B

References
1)

－77－

Masakazu KUNITOMO, Noboru TAKIGAWA, Kazuo
MAKISHIMA, Toshiro KAWAMOTO, Tatehiko KURODA,
Masanori KOBAYASHI, Teruo TAHARA, Michio HASHIMOTO,
Tetsuo Masubuchi: High school physics, (2006) 166.

P11
次世代宇宙用高機能ループヒートパイプの微小重力下での内部流動キャラクテリゼーション○松田雄太，三富将敬，福嶋一貴，常新雨，長野方星（名古屋大）
Internal Flow Characterization of Next-generation Space Intelligent Loop Heat Pipe under Microgravity○Yuta MATSUDA, Masataka MITOMI , Kazuki FUKUSHIMA, Xinyu CHANG, Hosei NAGANO (Nagoya Univ.)

1. Introduction
Loop heat pipes (LHP) are two phase heat transfer devices
which utilize the capillary forces developed in porous media andlatent heat at phase change of fluid. LHPs have been used forthermal control of spacecraft. However, more functional thermal
control devices are required. A multiple evaporators LHP(MLHP) is one of the solutions. In order to predict its
performance accurately, understanding of complex internal heatflow of the MLHP is required. In the past, observations of LHP

to the CC side. Bubbles in the core never connect to bubbles of
the CC (Fig. 2 (b), (c), (d)). Fig. 3 shows the internal
observation of the CC of the heated side. The vapor phase is at
the top of CC, the liquid phase is at the bottom of the CC under
1g (Fig. 3 (a)). Meanwhile the vapor phase moves in the centerof the core as a large bubble (Fig. 3 (b)).
BubbleBubbleBubble(b) 5Sec (0G)(c) 10Sec (0G)(d) 13Sec(0G)

Vapor phase
110-0W

under 1G are reported1, 2). Observation of LHP under g is also
reported3). However, there are no researches of visualizing(a) Start (1G)internal flow of MLHP under g. In this study, vapor-liquid

Fig.2

distribution in the evaporator under g is revealed.

Inside of the evaporator (Heated side)

Vapor phase

2. Experiments
Fig. 1 shows the scheme of the MLHP for visualization.
MLHP has two evaporators and compensation chambers (CCs).
Insertion opening is provided to each CC to observe the inside
by a bore scope. It is possible to observe both of the CC sideand the wick core side by rotating the bore scope. The
condenser is consisted by the transparent 1/8 inch tube made of
PFA and the A15052 plate of 150×300mm. The condenser iscooled by conduction cooling with sandwiching the refrigerant
and insulation between condenser plate and base plate.
Measurement of the temperature distribution is carried out by 34
T-type thermocouples. The pressure is measured by 4 pressuregauges. Microgravity experiments were held at Diamond Air
Service (DAS) in Komaki, Aichi. The available microgravity
time by a parabolic flight is around 20s3).

Vapor phase

Mirror image ofBayonet tube

Bayonet tube

Vapor-liquidinterface
Bayonet tube

Vapor-liquidinterface

LiquidLiquid(a) 1G(b) 0G

Fig. 3 inside of the CC (Heated side)
Fig. 4 shows the vapor-liquid distribution conceptual diagramof the heated evaporator and the CC. In the heating side, thevapor-liquid distribution follows gravity. The vapor phase is at
the top of the CC, the liquid phase is at the bottom of the CC(Fig. 4 (a)). On the other hand, the effect of surface tension
becomes dominant in g. Because of this, the liquid stick to thewall and the bubbles gather in the center of the core.
Wick

B
Vapor

A

Vapor

Vapor

Case

Case
LiquidBubbleA’ Wick
Bayonet tube A-A’
Liquid B’
Bayonet tube

LiquidCase

B-B’ Bayonet tube(a) Vapor-liquid Distribution Under 1g
Wick

B

Vapor

A

Vapor

Vapor

Case

Case
LiquidLiquidBayonet tube A-A’ Bubble

Fig. 1A’

Bayonet tube

Scheme of the MLHP

Wick

Liquid B’

Case

B-B’ Bayonet tube(b) Vapor-liquid Distribution Under gFig. 4

3. Result and Discussion
3.1 Vapor-liquid distribution in the evaporator and CC
Fig. 2 shows the internal observation of the evaporator of theheating side. Under 1g condition, the vapor phase is at the topof the core, and the liquid phase is at the bottom of the core (Fig.
2(a)). On the other hand, the vapor phase moves to the center ofthe core under g. After that, the bubbles grow so as to extend

Vapor-liquid distribution (Heated side)

References
1)
2)

B. P. d’Entremont, J. M. Ochterbeck, Proc. Of the ASME Summer
Heat Transfer Conference, 2, 387 (2008)
J. M. Climbala, J. S. Brenizer, Po-Ya Chuang, S. Hanna, C. T.

3)

Conroy, D. R. Riley, Appl. Radiat. Isot, 61 (2004) 701-705
T. Ogushi, A. Yao, J. J. Xu, H. Masumoto, M. Kawaji, The Japan－78－

of Society of Mechanical Engineers, 66,646 (2006) 230-235

P12
パラボリックフライトによる微小重力曝露が換気効率ならびに自律神経活動に及ぼす影響○平山佑介，前沢寿亨，田中雅侑，傳秋光，藤野英己（神戸大学）

Effects of Microgravity Induced by Parabolic Flight on Ventilation Efficiency and Autonomic
Nervous Activity○Yusuke HIRAYAMA, Toshiyuki MAEZAWA, Masayuki TANAKA, Akimitsu TSUTOU, Hidemi FUJINO(Kobe University)

Abstract
Gravity plays a major role to determine respiratory function.
For example, functional residual capacity (FRC) is reduced
under microgravity condition 1-2). The reduced FRC also
decreases ventilation efficiency. However, it is not clear that
acute effect of exposure to microgravity on ventilation efficiency.
In addition, the relationship between ventilation efficiency andautonomic nervous activity during microgravity exposure has
not been discussed. Therefore, we measured both ventilation
efficiency and autonomic nervous activity, and discussed thechanges under microgravity condition.
The data were divided into five phases by gravitational
acceleration (Fig1A). Microgravity resulted in a reduction of theventilation efficiency that was indicated by increase in minute・・

ventilation-to-oxygen consumption ratio (VE/VO2) and minute・・

ventilation-to-carbon dioxide production ratio (VE/VCO2) (Fig.
1B, C). In addition, the ratio of abdominal-to-thoracic motion(Vabd/Vrib) increased and the duration of expiratory phase of
respiration (TE/TTot) shortened during microgravity (Fig. 1D, E).
Furthermore, LF/HF in sympathetic nervous activity wasincreased under microgravity (Fig. 1F). However, these resultsin Vabd/Vrib, TE/TTot, and LF/HF were not consistent withprevious reports 1, 3). Finally, we observed using a videorecorder that subject’s trunk was extended during microgravity
exposure (Fig. 2).
It has been reported that abdominal motion becomes smaller
as trunk is extended 4). In addition, the decrease in theabdominal motion shortens expiratory time. Since prolonged
expiratory had decreases sympathetic nervous activity 5), thedecrease in the duration of expiratory phase might result inincreasing sympathetic nervous activity during microgravity
exposure. Therefore, the change of subject’s posture could
indirectly affect sympathetic nervous activity. These results
suggest that autonomic nervous activity does not always play
key role to regulate ventilation efficiency in case of exposure to
microgravity.

Fig. 1 Change of respiratory function and autonomic
nervous activity

Acknowledgement
This study was partly supported by the 11th student contest of
microgravity experiments using an aircraft. We thank Japanese
Aerospace Exploration Agency, Japanese Space Forum, andDIAMOND AIR SURVICE.

－79－

Fig. 2 Change of subject’s posture during 1G and 0G

References
1) M. Paiva, M. Estenne, L. A. Engel: J Appl Physiol (1985),
67 (1989). 1542-50.
2) D. Bettinelli, C. Kays, O. Bailliart, A. Capderou, P.
Techoueyres, J. L. Lachaud, P. Vaida, G. Miserocchi: J Appl
Physiol (1985), 93 (2002). 2044-52.
3) B. Verheyden, F. Beckers, A. E. Aubert: Eur J Appl Physiol,95 (2005). 557-68.

4) D. Paek, K. B. Kelly, F. D. McCool: J Appl Physiol (1985),
68 (1990). 2482-7.
5) T. Matsumoto, T. Masuda, K. Hotta, R. Shimizu, A. Ishii, T.
Kutsuna, K. Yamamoto, M. Hara, N. Takahira, A.
Matsunaga: Respir Physiol Neurobiol, 178 (2011). 275-82.

－80－

P13
微小重力下における炊飯器内を想定した
三相系熱輸送の観察および地上実験との比較○瀧本理仁，小林芳成，引地悠太（東京大）Observation of Three-Phase Heat Transportation Simulating a Rice Cooker and Its Comparison
between Microgravity and Ground Conditions○Rihito TAKIMOTO, Yoshinari KOBAYASHI , Yuta HIKICHI (Univ. of Tokyo)
1. Introduction
The astronaut food and diet is one of the important problems
in outer space. Taking food which are similar to what we usuallytake on earth is said to be effective to reduce stress in outerspace. For us Japanese, eating freshly cooked rice in outer space
is of great importance. Cooking rice contains physicalphenomenon that rice is heated under gas-liquid-solid threephase flow. Thermal convection caused by gravity play animportant role when cooking rice on earth. However, under
microgravity condition, heat convection does not occur because
buoyancy caused by density difference does not exist. Therefore,
there is a possibility of observation of other physicalphenomenon dominating the thermal transportation. A large
amount of study on heat transfer has been done including poolboiling and forced convective boiling using various
microgravity facilities such as parabolic flight on airplanes,
drop towers, and rockets, but no experiment has been done
based on cooking in microgravity. In this study, theexperimental vessels which contain water and rice is heated toboiling point in microgravity to obtain knowledge of the effectof microgravity condition on heat transportation of the liquidcontaining rice.

Fig.1 Schematic of Experimental Equipment

2. Experimental
The experiment was done during parabolic flight whichenables to create microgravity condition below 3×10-2G. The
experimental apparatus is shown in Figure 1. The experimental
apparatus consists of three parts including heating part,measuring part, and control part. It is difficult to cook rice fromthe beginning because duration of microgravity in thisexperiment is about 20s. Therefore, we used comparatively
small vessel (φ30mm×40mm) and measured the temperature
history while heating to the boiling point. The surface
temperature of the heater was kept to be 400℃ during groundcondition, and 500 ℃

during microgravity using K-type

thermocouple and heat regulator. The behavior of the boiling
fluid in microgravity was recorded using video camera (SONYHDR-CX430V) and history of temperature inside theexperimental vessel was recorded using data logger (OMRONZR-RX70).

Fig.2 The overall view of the experimental equipment

3. Results and Discussion
The behavior of boiling fluid in microgravity is shown in Fig.3.
The vessel of left figure contains 15cc of water and right vessel
contains 30cc of water. The bubbles formed during microgravity
didn`t coalesce and stayed individual. Bubbles formed frombottom surface that is closest to the heating part and the baby
bubbles grew while pushing up older bubbles. During thedevelopment of bubbles, rice grains were observed to stir up.
For the case of 15cc, the fluid stream up the wall of the vessel
due to surface tension, and we predicted that this effect may
enhance thermal transportation.

－81－

Fig.5 The hisory of temperature(20mm from the upper surface of the experimental vessel)

Fig.3 The behavior of the fluid while boiling in microgravity(Left: 30cc of water, Right:15cc of water)
The comparison figure of heat transportation between
microgravity and ground condition is shown in Fig.4-6.
Temperature history was measured at 10mm, 20mm, and 30mm
from the upper surface. For the case of Fig.4, the temperature in
microgravity doesn’t increase while it keeps increasing in 1g
condition. This suggests that the thermal transportation issuppressed in microgravity. Fig.5 doesn’t show clear difference
between microgravity and ground, but from Fig.6, you can seethat the temperature increases rapidly in microgravity condition
compared to ground condition. Also, in 1g condition, thetemperature seems to oscillate during heating. This may be due
to convection caused by boiling.

Fig.6 The hisory of temperature(30mm from the upper surface of the experimental vessel)

4. Conclusion
1.

Under microgravity condition, the boiling bubbles
stayed individual.
The thermal transportation was suppresed in
microgravity condition compared to ground condition.

2.

3.

Thermal concentration near heating surface was moresignificant under microgravity compared to groundcondition.

References
Fig.4 The hisory of temperature(20mm from the upper surface of the experimental vessel)

1)

NASA: Space food and nutrition An Educator’s Guide with
Activities in Science and Mathematics, 1999

2)

A. F. Witt, H. C. Gatos, M. Lichtensteiger, M.C. Lavine and C. J.
Herman: J. Electrochem. Soc., 122 (1975) 276.

3)

K. W. Benz and G. Nagel: Proc. 5th Europ. Symp. Mat. Sci. under
Microgravity, Schloss Elmau, FRG, Nov. 1984, 157

4)

Johannes Straub; Boiling heat transfer and bubble dynamics inmicrogravity, Advances in Heat Transfer, 35 (2001) 57-172

－82－

P14
微細流路内における非共沸混合媒体の強制流動沸騰熱伝達○梅野晃太郎，岩田圭介，山崎優佑，大田治彦（九州大）

Flow Boiling Heat Transfer of Non-Azeotropic Binary Mixture in a Small-Diameter Tube
○Kotaro UMENO, Keisuke IWATA, Yusuke YAMASAKI and Haruhiko OHTA (Kyushu Univ.)
1. Introduction

Table 1In the thermal management system for space application, thedevelopment of the system which has no gravity effect is desired
for reliable operation after ground tests. Flow boiling in minitube is one of the promising means for cooling at high heat flux
density because its interfacial behaviors and heat transfer are
dominated by surface tension.
However, the flow fluctuation and partial dryout occur inflow boiling in mini tube because the vapor bubble growtowards also upstream and fill cross-section of the tube. As aconsequence, no coherent experimental data was obtained so far,and it varies with different experimental manners and devices
employed. To suppress flow fluctuation and to avoid theresulting partial dryout are essential requirement to clarify heattransfer characteristics in mini tubes.
We focus attention on the characteristics of non-azeotropic
binary mixture such as alcohol aqueous solutions to reduce thevapor bubble growth rate by the mass transfer resistanceexisting inherently in the mixtures in order to suppress the flow
fluctuation [1].

Experimental conditions.

Tube inner diameter

di = 0.51mm

Mass velocity

G = 100 – 200kg/m2s

2, 5, 10, 15, 20,72(Az.)
wt% of 1-Propanol
Test fluid
2, 4, 6, 7.15 wt%
1-Butanol/Waterof 1-Butanol
Outlet pressure
Pout = 0.101MPa
1-Propanol/Water

Heated length

L = 100mm

Heat flux

q = 70 – 120 kW/m2

3. Experimental results
Saturated value of fluid temperature is evaluated from theliquid-vapor equilibrium diagram (Fig.2). Under saturated
conditions, the increase of fluid temperature along the tube axis
due to the preferential evaporation of more volatile component
is calculated by the heat balance equation. Fig.3 shows
distribution of wall temperature Tw and fluid temperature Tf
along the tube axis for 1-Propanol/Water (15wt% of 1-propanol)

2. Experimental Apparatus

at G = 100kg/m2s and q = 85kW/m2. Fig.4 shows the relation
between heat transfer coefficient α and vapor quality x at

The outline of experimental apparatus is shown in Fig.1. The
test section is a 0.51mm-diameter single mini-tube heateddirectly by the passage of alternative current. Nineteen
thermocouples are soldered on the outer wall to evaluate thelocal heat transfer along the tube. The experimental conditions

different heat fluxes. Fig.5 and 6 show the transition of pressure
drop ΔP corresponding to the flow rate fluctuation in the heatedtube and of wall temperature Tw at z = 35mm from the inlet ofheated test section for pure water and 1-Propanol/Water (15wt%
of 1-propanol). The results are summarized as follows.

are summarized in Table 1. 1-Propanol/Water and 1Butanol/Water are used as test fluids varying mass concentration
under different combinations of mass velocity G and heat flux q.

1. At x = 0.06 - 0.1, heat transfer coefficient drop sharply
because of the overshooting of wall temperature at theincipience of nucleate boiling.
2. Under the saturated condition of Fig.3, the wall temperaturerises gradually which is consistent with the increased fluid
temperature obtained from the calculation under theassumption of almost constant region.
3. In Fig.4, heat transfer coefficient decreases with increasingheat flux after the initiation of boiling. The trend is against
the effect of heat flux on nucleate boiling heat transfer but isconsistent with the effect of partial dryout which isemphasized at higher heat flux.
4. The use of single-component water or alcohol, a large flow
fluctuation is observed, while it is drastically suppressed by

Fig.1

using aqueous solutions (Fig.5 and 6). The result is along
the objective of the present study.

Experimental apparatus.

－83－4. Concluding remarks
1-Propanol/Water
375 P = 0.1MPa

370

T℃

The use of non-azeotropic mixtures seems to become a key
technology to stabilize flow boiling in mini tubes in theapplication to the cooling of electronic devices with high heat
flux density. However, it is well known that the heat transfer
coefficient due to nucleate boiling of non-azeotropic mixture
deteriorates from that of the single component liquid with thesame thermal properties as the relevant mixture or from theinterpolated value of heat transfer coefficient between those of
single components. Further investigation is needed to evaluate
the heat transfer characteristics for mixtures in flow boiling of
mixtures in the entire quality range.

365

360
0

0.4

0.6

0.8

1

Weight fraction of 1-Propanol

5. ReferencesFig.2

liquid-vapor equilibrium diagram.

J.R. Thome and R.A.W. shock, "Boiling of Multicomponent
Liquid Mixtures", Advances in Heat Transfer, Academic Press,
Vol.16, 1984, pp. 59-156.

150 1-Propanol/Water(15wt%)
5

2

10

q = 85 kW/m

 W/m2K

T℃

Pout = 0.1MPa
G = 100kg/m2s

100
Tw
Tf

1-Propanol/Water(15wt%)
Pout = 0.1MPa
G = 100kg/m2s
q = 75 kW/m22
q = 80 kW/m2
q = 85 kW/m2
q = 90 kW/m2
q = 95 kW/m

104

50
0

20

60

Fig. 3Distribution of wall temperature

z mm

80

10-2

100

Heat transfer coefficient α

versus vapor quality x.

3

Tw ℃

2.5

90

2.5

90

P

P

Tw
20

40

60

Tw
80

80
100

2
0

Time sFig. 5100

Water/1-Propanol(15wt%)
Pout = 0.1MPa
G = 100kg/m 2s
q = 80 kW/m 2

P kPa100

Water
Pout = 0.1MPa
G = 100kg/m 2s
q = 80 kW/m 2

2
0

100

x

Fig. 4

Tw and fluid temperature Tf .

3

10-1

Tw ℃

40

P kPa

1)

0.2

20

40

60

80

80
100

Time sFluctuation of flow rate represented by

Fig. 6

Fluctuation of flow rate represented by thethe pressure drop ΔP and of wall temperature Tw

pressure drop ΔP and of wall temperature Tw at z =at z = 35mm for pure water.

35mm for 1-Propanol/Water (15wt% of 1-propanol).

－84－

P15
一成分二相流のボイド率特性に及ぼす管径の影響○五明泰作，浅野等（神戸大学）

Effect of Tube Diameter on Void Fraction Characteristics of One-Component
Gas-Liquid Two-Phase Flow
○Taisaku GOMYO, Hitoshi ASANO (Kobe Univ.)
Mishima-Ishii’s transition boundaries when semi-annular flow
was included in slug flow.
Average void fractions for annular flow were arranged based

1. Introduction

on drift-flux model, as shown in Fig. 3(a), (b). For 4.0 mm,
average void fraction measured by capacitance sensor, ave,
agreed well with the Ishii’s annular flow model(3). However, for
2.0 mm, the Ishii’s model over-estimates a little. The reason
might be on the flow behaviors. Void fraction at lower jL might
be lower due to higher liquid velosity with large waves.
100

jL [m/s]

10

10

Slug
AnnularSemi-annular
Churn
Churn
Slug

10-3 -2
10

10-1

Annular100

jG [m/s]

10-3 -2
10

10-1

Annular100

jG [m/s](b) Din = 2.0 mm.

Annular flow
(3)
Ishii's annular flow model

6

6

jG/ave [m/s]Annular flow
(3)
Ishii's annular flow model

4

2

4

2

0
0

2

4

6

jT [m/s]jT [m/s](a) Din = 4.0 mm.

(b) Din = 2.0 mm.

Fig. 3

Capacitance sensor for void fraction measurement.

Average void fractions arranged based on the driftflux model.

References
1)

T. Gomyo, H. Asano, H, Ohta, Y. Shinmoto, O. Kawanami, T.
Kurimoto, M. Komasaki, A. Matsumoto, Japanese Journal of
Muntiphase Flow, 27, 5, 2014, 547-554

2)

K. Mishima, M. Ishii, Int. J. Heat Mass Transfer, 27, 1984, 723737

3)

M. Ishii, ANL Report, ANL-77-47, 1977

(2)transition boundaries are shown in Fig.2(a), (b), respectively.
The flow pattern transition boundaries agreed well with the101

Flow pattern map with Mishima-Ishii’s transition
boundaries(2).

00 1 2 3 4 5 6

3. Experimental results
Flow patterns observed in the test section were classified into
bubble flow, slug flow, churn flow, semi-annular flow, andannular flow for each tube diameter. Churn flow was defined as
the flow with intermittent liquid reverse flows. The flow patternmaps for 4.0 and 2.0 mm tubes with the Mishima-Ishii’s

Slug
AnnularSemi-annular
Churn
Churn
Slug

10-2

(a) Din = 4.0 mm.
Fig. 2

observation section with the configuration as shown in Fig. 1(1).
In the observation section, void fraction measurement by acapacitance sensor and flow behavior observation by a highspeed camera were conducted simultaneously. The detail of themeasurement was reported in the previous report (1).

Fig. 1-1

jG/ave [m/s]Vertical upward two-phase flows were examined for 2.0 and
4.0 mm diameter tubes. FC-72 was used as the refrigerant. The
refrigerant was circulated by a gear pump. The inlet conditions
were maintained by heat input at a pre-heater and a main heater,
and then two-phase flow was supplied to the vertical

BubbleBubble-1

10-2

2. Experimental setup

Mishima-Ishii's equation

Mishima-Ishii's equation

100

jL [m/s]

Two-phase flow loop system has been attracting attention as acooling and temperature control system for space structure. For
the design of this system used in space, it is important to clarify
the two-phase flow dynamics under microgravity. In a reduced
gravity condition, the effect of surface tension on two-phaseflow behaviors becomes larger. On the other hand, the effectalso becomes larger with decreasing the channel diameter. In
this paper, the transition of dominant force, especially between
gravity and surface tension, and gravity and inertia force, wasdiscussed based on void fraction characteristics. Void fraction
was measured by a capacitance method.

－85－

101

P16
ガスジェット浮遊法を用いた C12A7 エレクトライドの作成における酸素分圧の影響○松原宏次，水野章敏，渡邉匡人（学習院大）

Effect of Oxygen Partial Pressure on Preparation of C12A7 Electride by using Conical Nozzle
Levitation○Koji MATSUBARA, Akitoshi MIZUNO, Masahito WATANABE(Department of Physics, Gakushuin University)
1. Introduction
The compound 12CaO-7Al2O3 (C12A7) is well known

solidified in the Ar/H2(7%) atmosphere, the color ofas an insulator used for cement raw materials. However, it

C12A7 sample was reported as a peculiar feature of

was recently discovered that the compound became the

C12A7 electride. 1) This indicates that the reducing

conductive material called the electride by replacing an

condition due to the Ar/H2(7%) gas promoted aoxygen ion loosely bound in the cage structure with an

substitution of an oxygen ion in the cage to an electron.

electron.

1)

The C12A7 electride can be prepared bysample showed dark green. The dark green coloring of

By increasing the internal pressure in the chamber fromextracting an oxygen ion in the cage structure under the

1 atm

reducing atmosphere. In addition, the vitrification of theAr/H2(7%) atmosphere was pronounced. Furthermore,

C12A7 electride has been also reported.2) In this case, it iswhen keeping the melt at 2073 K before cooling, thenecessary to use a quenching method to vitrify the C12A7

coloring of sample in the Ar/H2(7%) atmosphere wasmelt. Therefore, we made an attempt to prepare thepromoted than keeping it at 2273 K. Meanwhile, a distinct

C12A7 electride glass by using the conical nozzle

difference was not observed by changing the keeping timelevitation (CNL) technique which is known as a method toof the melt.

to 1.5 atm, the coloring of sample in the

suppress a nucleation in a melt efficiently. In this study,

In this talk, we will discuss an effect of oxygen partial

we investigated an influence of the oxygen partialpressure on preparation of C12A7 electride by usingpressure on solidification of the C12A7 melt underconical nozzle levitation.

different gas environments around the sample.
2. Experiment
Figure 1 shows the schematic illustration of the CNL
apparatus. A spherical sample of C12A7 compound about
2 mm in diameter was prepared from a powder of CaO
and Al2O3 by melting with the use of a CO2 laser.
Containerless solidification of the C12A7 compound was
conducted under different gas environments. We used
three kinds of gas, air (PO2=2×104 Pa), Ar (PO2=10 Pa)
and Ar/H2(7%) (PO2=10-19 Pa), which have different
oxygen partial pressure. In addition, we investigated a

Fig.1 Schematic illustration of experimental set up using theconical nozzle levitation apparatus.

influence of the sample temperature, heating time andinternal pressure in the chamber.
3. Results and discussion
Figure 2 shows the C12A7 samples solidified under thedifferentgas

atmospheres.

Conventional

XRD

measurements confirmed that the samples vitrified. It was
found that the sample became transparent when solidified
in the air or the Ar atmospheres. On the other hand, whenFig.2 The C12A7 samples solidified by using conical nozzle
levitation under different gas atmospheres.

References
1)
2)

－86－

S. Matsuishi et al., Science, 301, (2003) 626
S. W. Kim et al., Science, 333, (2011) 71

P17
過冷メルトからの急速凝固における Double Recalescence○加藤寛隆，永山勝久（芝浦工大），稲富裕光，M. S. Vijaya KUMAR，栗林一彦（ISAS/JAXA）

Double Recalescence during Rapid Solidification into Undercooled Melt
○Hirotaka KATO, Katsuhisa NAGAYAMA, Yuko INATOMI, M. S. Vijaya KUMAR
and Kazuhiko KURIBAYASHII

1. Introduction
On the thermodynamic criterion for forming a metastablephase from undercooled melt (Mat. Sci. Eng. A, 449-451 (2007)675), we carried out the containerless solidification to verify thevalidity of the criterion using LuFeO3 as the model material. In
LuFeO3, hexagonal modification (h-LuFeO3) was formed as themetastable phase and the criterion was well satisfied. In YbFeO3,
however, X-ray diffraction shows the mixed structure of hLuFeO3 and o-YbFeO3 (orthorhombic perovskite). This result
suggests that o-YbFeO3 also nucleated although the criterion for
h-LuFeO3 to nucleate is satisfied. In this study, in order to makeclear the reason why the mixed structure is constituted in thesample of YbFeO3, we observe precisely the solidification
sequence using a high-speed video (HSV) and investigate thethermodynamic condition.

2. Experimental

Figure 1 shows the typical T-t curves of YbFeO3. In thisfigure, the curve after the recalescence is unsteady comparedwith that before the recalescence. This unsteadiness is owing to
the unstable positioning of the sample in the conical nozzle
because h-YbFeO3 shaped a polyhedron similar to that of
LuFeO3. However, the peculiar point that is different from thecurve of the LuFeO3 sample is that the post-recalescencetemperature shows two stages, corresponding to double
recalescence. Post-recalescence temperature TE,s, undercoolingTs and hyper-cooling limit Thyp, which are required foranalysis of the criterion, are 1848 K, 97 K and 240 K,
respectively. The critical index calculated by using these values
obviously satisfy the criterion. Nevertheless, mixed structurewith o-YbFeO3 was formed in the as-solidified sample. The firststages are approximately at 1850 K and the hyper-cooling limit
at 1890 K, respectively.

As a tool for performing the sample to undercool, we usedaero-dynamic levitator ADL. The spherical sample which istrapped inside the conical nozzle of ADL by the pressure
difference of oxygen gas was melted completely by theirradiation of CO2 laser beam from the top of the nozzle. The
temperature of samples was measured with a mono-color
pyrometer, whose sampling rate and the emissivity were fixed to
1 kHz and 0.8, respectively.

3. Results and Discussion

Fig. 2. HSV images of YbFeO3 captured during recalescence. The
frames are taken at a time interval of 0.001 s, and the elapsed time
indicated in each image was set to 0 s for one frame before thenucleation.

Figure 2 shows the HSV-images captured during therecalescence. As time t passes from the onset of recalescence,
the form of the sample changes to a polyhedral shape fromspherical one. If the first recalescence corresponds to forming
the metastable h-YbFeO3, the T-t curve must satisfy the criterion
for forming the metastable phase. In fact, the critical index, c,Fig. 1. Temperature-time relation of YbFeO3.

is larger than 1.0; that means the criterion is satisfied. However,the second recalescence suggests the competition between
growth of the metastable phase and the nucleation of the stablephase. Based on this suggestion, we regard this competition asthe decisive factor for double recalescence, and calculated therelative relation of the activation energies for forming a 2D
nucleus of h-LnFeO3 and a heterogeneous nucleus of o-LnFeO3.
According to the neg-entropy model for the interfacial freeenergy, the activation energies for forming a 2D nucleus G*2D
and a heterogeneous nucleus G*hetero are respectively given by2
πh 2 S ms
f T

G2*D N V  T
2 23
A m

*
Ghetero,(1)f   .

(2)

ms

16π 3S sf T 3

 

3N AVm2 T s

2where NA, Vm, Sf, T, h,  l, and GV are Avogadro’s number,

Fig. 3. Relation between Gn* for 2D homo-epitaxial nucleus ofmolar volume, entropy of fusion, temperature, ledge height of
2D nucleus, interfacial free–energy and Gibbs free-energy

and 3D heterogeous nucleus and T .

Therefore, if the melt of LuFeO3 is undercooled to thedifference, respectively. f() that is acatalytic potency fortemperature T  0.98 , that is approximately 0.4 % lower thanheterogeneous nucleation, depends on the contact angle  of a
nucleus cap to a substrate and is given by

(

()

)

1
f q = 2 - 3cosq + cos3 q .
4
By using the relation Vm=h3NA, the dimensionless forms of Eqs.
1 and 2 are expressed as follows:G2*D ms 2
πC p ThypTs
2πC p Thyp
T

3

 

3N A 1  T

2

T

ms

,

(3)

T 

T
TEs

, T ms TEs

as a result, double recalescence does not occur. On the other
hand, even if the criterion for forming a metastable phase issatisfied and f() is 0.02, the double recalescence occurs and theof the cases of these materials.

f   ,and T solidified sample whose T ms is less than 0.975, because in thissample G2D* is absolutely larger than G*hetero. YbFeO3 is one

(4)

where
s

G*hetero of o-LuFeO3, under the condition that f() is 0.02, and,mixed structure of h-LnFeO3 and o-LnFeO3 is formed in the as-

4 N A T ms  T ms  T *
GheteroTEms of h-LuFeO3,G*2D of h-LuFeO3 becomes smaller than

T
TEs

.

Figure 3 shows G*2D and G*hetero as a function of T . In
this figure, T ms and f() were used as parameters under theassumption that Thypms is half of Thyps: G2D* was calculated
for two cases: one is that T ms ’s are 0.984, the other is 0.974;
those are the dimensionless melting temperatures of h-LuFeO3
and h-YbFeO3, respectively. On the other hand, as for G*hetero,three cases that f()’s are 0.01, 0.02, and 0.05 are calculated.

4. Summary
In YbFeO3, double recalescence that suggests the nucleation oforthorhombic perovskite was observed although the criterion forforming a metastable phase was satisfied. The analysis of theactivation energies for forming a two dimensional nucleation ofmetastable phase and the heterogeneous nucleation of stablephase shows that double recalescence occurs if the difference ofmelting temperatures of stable phase and metastable phase islarge and the undercooling is smaller than the critical ones. If
compared the melting temperature of YbFeO3 with that of
LuFeO3, the former is 1 % larger than the latter; This differenceis sufficient for double recalescence to occur.

P18
InGaSb 結晶成長に対する重力効果―国際宇宙ステーション内の微小重力下と 1G 下実験―
○Velu NIRMAL KUMAR, Mukannan ARIVANANDHAN, Govindasamy RAJESH, 小山忠信,

百瀬与志美（静岡大），稲富裕光， 阪田薫穂，石川毅彦，高柳昌弘,上垣内茂樹（JAXA），
小澤哲夫（静岡理工科大），岡野泰則（大阪大），早川泰弘（静岡大）Effect of Gravity on InGaSb Crystal Growth―Microgravity at International Space Station and 1G Conditions―○Velu NIRMAL KUMAR, Mukannan ARIVANANDHAN, Govindasamy RAJESH, Tadanobu KOYOMA,
Yoshimi MOMOSE (Shizuoka Univ.), Yuko INATOMI, Kaoruho SAKATA, Takehiko ISHIKAWA,
Masahiro TAKAYANAGI, Shigeki KAMIGAICHI (JAXA), Tetsuo OZAWA (Shizuoka Inst. Sci. Tech.),Yasunori OKANO (Osaka Univ.), Yasuhiro HAYAKAWA (Shizuoka Univ.)
1. Introduction
InGaSb, a ternary alloy semiconductor having tunable lattice
constant and wavelength ranging 6.096 ~ 6.479 Å and 1.7 ~ 6.8
μm is a potential material for thermo photovoltaic and IR
detector applications1). Since the high temperature solution
growth process is affected by solute convection on earth, it isimportant to understand the growth kinetic due to solute andheat transport. Microgravity is an ideal condition to study
growth kinetics of crystals due to the suppression of convection.
In the present study, we have grown InGaSb crystals under
microgravity at International Space Station as well as on earth
and investigated the effect of gravity on the growth.

2. Experiment
The growth experiments were carried on earth andmicrogravity conditions by vertical gradient freezing method
using the sandwich structure of sample GaSb(seed)/Te-doped
InSb/GaSb(feed). Prepared sample was heated at around 700 ˚Cwith temperature gradient 0.6 ˚C/mm and heat pulses at 2 hinterval were applied to measure the growth rate. The grown
crystals were cut along (110) plane after taking Laue pattern.
Cut crystals were mirror polished and analyzed by electronprobe micro analysis (EPMA). The growth striations wererevealed by etching with 1:3:1 ratio of HF : KMnO4 :CH3COOH for 30 min. at room temperature.

Fig. 1 (a) Indium composition profile and (b) indium
mapping of microgravity and earth grown samples.
The observed growth striations (marked with red lines forclear visibility) of microgravity and earth grown samples areshown in Fig. 2(a) and (b). It also revealed that the shape ofgrowth interface was almost flat in microgravity sample whereas
it was concavely curved in earth grown sample owing tosolution convection at higher temperature. The maximum
growth rate was calculated to be 0.149 and 0.103 mm/h for
InGaSb crystal grown under microgravity and on earth,respectively.

3. Results and discussions
Fig. 1 (a) shows indium composition profile of InGaSb
crystals grown under microgravity and on earth. It revealed
gradual decrease of indium composition along growth direction
owing to shift in growth interface towards high temperature feed
region. Dissolution of seed on earth (4.9 mm) was larger than
microgravity (2.3 mm) due to strong convection and it is inagreement with the numerical simulations2). EPMA mapping in
Fig. 1 (b) revealed that the growth interface shape was flat under
microgravity and curved concavely towards feed in the earthgrown sample. It conformed the dominant melt convection onearth and convection free growth under microgravity.

Fig. 2 Growth striations of (a) microgravity and (b) earthgrown samples

References
1)

P. S. Dutta, H.L. Bhat and V. Kumar: J. Appl. Phys., 81 (1997)
5821.

2)

M. Nobeoka, Y. Takagi, Y. Okano, Y. Hayakawa and S. Dost:－89－

J. Crystal Growth, 385 (2014) 66

P19
温度差マランゴニ効果による自由液膜内対流 -液膜形状が基本対流場に及ぼす影響○費林昊（東理大院学），金子敏宏（東理大），上野一郎（東理大）Effect of Static Deformation on Basic Flow Patterns in Thermocapillary-Driven Free Liquid
Film○Linhao Fei1, Toshihiro KANEKO2, 3, Ichiro UENO2, 3
1

Div. Mechanical Engineering, Graduate School of Science & Technology, Tokyo Univ. Science2

Dept. Mechanical Engineering Fac. Science & Technology, Tokyo Univ. Science3

Research Institute for Science & Technology (RIST), Tokyo Univ. Science

1. Introduction
Fluid has in general negative temperature coefficient of
surface tension; the fluid over the free surface is driven from ahigher-temperature region to a lower-temperature region. In thecase of a thin free liquid film with two free surfaces, however, aunique flow pattern is realized. Dr. Donald R. Pettit, a NASA
astronaut, demonstrated a series of experiments in theInternational Space Station in 2003[1]. Among the fabulous
demonstrations, he prepared a thin liquid film of water in a ring
made by metal wire, and placed a heated iron close to one edgeof the film. What he realized was that the fluid was driven in thefilm toward the heated iron, that is, from a colder region to ahotter region (Fig. 1). After this demonstration, there had been
discussion on the mechanism of such a unique fluid motion.
Ueno & Torii [2] demonstrated the thermocapillary-driven flow
in a rectangular thin free liquid film in the terrestrial
experiments. They indicated that there exist two major basic
flows as a function of the shape of the liquid film in terms ofaspect ratio by preparing a quite thin liquid film less than 1 mm
in thickness to prevent the breakage of the film due to thenormal gravity. The direction of the net flow, however, was fromthe hotter end to the colder one as generally expected.

the effect of the volume ratio was numerically investigated by
Yamamoto et al. in 2013[5]; they proposed that the direction of
the net flow is governed by the vortex shape near the hot-end
region.
The flow structures inside the film, however, have never been
experimentally indicated because of the unique target geometry
with deformation free surface. In order to understand themechanism how the fluid chooses the direction of the net flow,
there is no doubt that the information of the flow structuresinside the film is indispensable. In the present study, we focus
on the flow structures of the thermocapillary convection in across section normal to the end walls. We will present our latest
results of our measurements in the poster.

2. Experimental Setup
Figure 2 represents the target geometry of the thin free liquid
film, and apparatus in the present study. A liquid film is formed
in a rectangular hole in the middle of a glass plate. A designatedconstant temperature difference T is added to both end walls.
A thin liquid film of designated volume V is formed inside
the hole. The 6-cSt silicone oil of 83 in Prandtl number (at25 °C) is employed as the test fluid. The shape of the liquid filmis described with three parameters[3], that is, the aspect ratios x= Lz/Lx and y = Lx/d, and the volume ratio V/V0, where Lx, dand Lz are the lengths in x, y and z direction, respectively, and
V0 is the volume of the hole LxdLz. We prepare two kinds of theplate; 0.6 mm and 0.2 mm in thickness. We define theFig. 1Marangoni number Ma = |d/Lx in order to indicate

Experiments on fluid dynamics by Dr. Donald Roy
Pettit[1]. The fluid in a thin free liquid film is driven
toward the heated area.

In 2010, Ueno et al.[3] firstly indicated by their experimentsthat the direction of the net flow by thermocapillary-effect in arectangular thin liquid film is governed by the volume ratio of
the film. In the case of the “fat” film, the direction is from thecolder end to the hotter end, which corresponds to the result by
Dr. Pettit. In the case of “thinner” film, on the other hand, thefluid is driven toward the colder end as indicated numerically by
Kawamura et al.[4], and as indicated experimentally[2]. Recently,

the intensity of the thermocapillary effect.
We monitor the surface temperature variation with theinfrared (IR) camera, and the static profile of the film with thelaser displacement sensor. In order to visualized the flow
patterns, florescent particles of 13 m in diameter are dispersedin the fluid of the film. The flow pattern in x-z plane is
integratedly detected through the bottom free surface of the filmby the whole illumination, and the pattern in x-y plane as the
cross-sectional view is detected through the side wall of theplate. We prepare the laser light sheet of 0.3 mm in thickness todetect the cross-sectional view.

－90－Fig. 2

Target geometry: a free liquid film exposed to atemperature gradient

2. Results and Discussion
In the present abstract, we focus on the results in the case of
the liquid film in the plate of 0.6 mm in thickness, and (x, y) =(2, 3.33). The temperature difference T is fixed at 6 K, whichcorresponds to Ma = 1.8×102. Under this condition, the flow
patterns realized in the film exhibit a transition from “singlelayered” flow to “double-layered” flow by varying the volume
ratio[4].
Figure 3 indicates the results in the case of V/V 0 = 0.75. This
figure consists of (a) the snapshot of the surface temperature
obtained by the IR camera, (b) typical example of the particle
path line observed from beneath (exposure time: 1.5 s), (c)profiles of the liquid film along x direction at different z, and (d)the typical example of the cross-sectional view of the particle
path line in x-y plane at z = 2 mm (the center line) (exposure
time: 1.5 s). In the frames of (b) and (d), arrows are added inorder to illustrate the direction of the convection. As the Prandtl
number of the test liquid is high, the temperature field is quite
concurrent with the convective field. From the IR image and theparticle path line observed from beneath, a single-layered flowis realized as observed by Ueno & Torii [3]; that is, a pair ofvortexes exists in the span-wise direction. The vortexes are
symmetrical with respect to the center line along the x direction.
The fluid flows from hot wall to cold wall in the middle of thefilm along the center line. Frame (c) indicates that the profiles
do not change drastically in x-y plane at different z. And, theconvection under this condition does not affect the profile along
x direction. From frame (d), the structure of convective field in
x-y plane at z = 2 mm is clearly observed. Fluid comes into x-yplane along z direction near the hot wall. Then it flows from hotwall to cold wall over the free surfaces, rolling and turning
sideward along z direction near the cold wall. A pair of vortexes
exists in x-y plane near the cold wall to form double-layered
structure in the depth direction. In the region near the hot wall,on the other hand, a “single-layered” structure is formed. It is
firstly revealed that the so-called “single-layered” flow definedby Ueno & Torii [3] consists of two major regions along thecenter line.

Fig. 3 Experimental results for (Lx, d, Lz) = (2 mm, 0.6 mm, 4mm) under V/V0 = 0.75: (a) snapshot of the temperatureof the top surface by IR camera, (b) particle path lines
for 1.5 s observed from beneath, (c) profiles of liquidfilm and (d) particle path lines obtained from the side.
Noted that all results are obtained in a single experiment
run but not-simultaneously.
Flow patterns change with aspect ratio and volume ratio. We
will discuss with more results by varying these parameters in theposter.

4. References1)

http://science.nasa.gov/headlines/y2003/25feb_nosoap.htm

2)

I. Ueno & T. Torii: Acta Astronautic, 66 (2010) 1017-1021.

3)

I. Ueno, T. Katsuta & T. Watanabe: Proc. 2nd European
Conf. on Microfluidics, 12 (2010) 1-9.

4)

H. Kawamura, K. Iwamoto and M. Harashima: Journal of
the Japan Society of Microgravity Application, 23 (2006)
157-160

5)

T. Yamamoto, Y. Takagi, Y. Okano and S. Dost: Phys.
Fluids, 25 (2013) 082108.

－91－

P20
水平円形伝熱面を用いた気泡微細化沸騰と伝熱面内温度分布の関連性について○堀内和菜（東理大），安藤洵（東理大院），金子敏宏（東理大），上野一郎（東理大）Correlation of Microbubble Emission Boiling on a Horizontal Circular Plate with Temperature
Distribution of Heating Surface○Kazuna HORIUCHI1, Jun ANDO2, Toshihiro KANEKO1, 3, Ichiro UENO1, 3
1

Dept. Mechanical Engineering Fac. Science & Technology, Tokyo Univ. Science

2

Div. Mechanical Engineering, Graduate School of Science & Technology, Tokyo Univ. Science3

Research Institute for Science & Technology (RIST), Tokyo Univ. Science

1. Introduction
Recently, many people have requested improvement ofcooling devices for developing highly-compacted and highly
efficient electric devices. Boiling heat transfer with a liquidvapor phase change accompanying a latent heat has been
attracting rising attention because it indicates higher heat flux
than the one that of single-phase cooling device. Under gcondition, however, heat-transfer efficiency drastically decreases
because of the effect of derived vapor stagnating on the heating
surface1). A unique phenomenon named microbubble emission
boiling (MEB) 2) has been introduced to solve this problem. The
MEB is a regime of the subcooled boiling in which the heat flux
exceeds the upper limit of the heat flux, called critical heat flux
(CHF), accompanying emission of the microbubbles of theorder of 10-6 m in radius from heating surface. By the reasonsstated above, the MEB is as a potential phenomenon for cooling

was measured in the preliminary experiments in order toconvince ourselves that a designated temperature is realized far
apart the heating surface. The degree of subcooling was definedby using that temperature. The diameter of the heating surface(ф) is 5, 10 and 15 mm. Four thermocouples are placed in thecopper block, three of them are placed along the center of theblock. Each thermocouple is positioned at 1, 3 and 5mm fromthe surface of the rod. The other is placed at 1-mm depth fromthe heating surface and 1-mm depth from the side wall of thecopper rod. The temperature and the heat flux on the heating
surface are evaluated from the temperatures along the center lineof the rod using Fourier’s law under assumption of onedimensional steady heat conduction. The behavior of the vapor
bubbles on the heating surface is tracked by using a high-speed
camera with a frame rate up to 30,000 fps under a back-lighting
system.

devices under g conditions. Although a number of experiments
e.g. 3, 4)

have been conducted to indicate its occurring conditions
and the heat transfer coefficient, the mechanism itself ofrealizing high heat flux has not been elucidated clearly yet.
In this study, we have conducted experiments focusing on thecorrelation of the MEB on a horizontal circular plate. We
especially focus on the uniformity of the boiling regimes overthe heating surfaces of different size.

2. Experimental apparatus
Figure 1 shows a schematic view of the experimental
apparatus. The copper block with a cylindrical rod is heated by
cartridge heaters. The copper-rod surface is the test section. In
prior to the series of experiments, we sanded the heating surface
by using emery papers of #1000 to unify its roughness. After
that, we cleaned the copper block using acetone. The block is
installed the bottom of the test chamber, the surface of thecopper rod only exposed to the test fluid. The chamber ispartially filled the distilled water as the test fluid. The coolingchannel made of copper was installed in the test fluid in order todefine the degree of subcooling. The temperature distribution

Fig. 1

Experimental apparatus

3. Results and discussion
3.1 Boiling curve
Figure 2 indicates the boiling curves in the case of ф = 10 mm.
Under the condition ΔTsub = 0 and 10 K, after the heat flux
reaches the CHF point, a significant “jump” of the wall
superheat emerges and the heat flux decreased drastically torealize the film or transient boiling. On the other hand, under－92－

the condition Δ Tsub ≧ 20 K, even though the heat flux
reaches CHF, heat flux is not decreasing but increasing with thewall superheat. This regime is called “MEB,” and a typicalexample of the vapor bubbles’ behavior over the heating surface
is shown in Fig. 3 .In this regime, smaller vapor bubbles cover
the surface and violently bounce up and down over the surface.
Such a bouncing of the vapor bubbles is always accompanied by
the MEB.

Fig. 4(a) Successive images of the condensing vapor

bubbles on the heating surface under ΔTsub =30 K and q = 4.67
MW/m2. Frame interval Δt = 35 ms and the shutter speed =1/10000 s. Frame (a’) indicates zoomed view of the rightheating surface of (a).

Summary
Boiling curve under ΔTsub = 0, 10, 20, 30 and 40 K

･Experimental study on the microbubble emission boiling in awith the boiling on the heating surface of 10 mm in diameter.
Each point except null ones plot when temperature becomessteady. Dashed arrow represent significant jump of temperaturepool is conducted by focusing on the bubble behaviors and theheated surface.

under ΔTsub = 20 K.

this regime, the vapor bubbles on the heated surface bounce up
and down with shooting out microbubbles in all directions.
After the onset of MEB, The heat flux increase with the wall
superheat.

Fig. 2･The MEB occurs under the condition ΔTsub ≧ 20 K. During･From the observation on the heating plate, we assume that
Fig. 3

Successive images of the MEB under ΔTsub =30 K

there is the coalesced bubble near the center, while the nucleateboiling still activity at the edge of the surface.

and q= 5.46 MW/m2. Frame interval Δt= 4 ms and the shutter
speed = 1/10000 s.

References

3.2 Behavior of vapor bubbles
Under the condition near the CHF point, the vapor forms
coalesced bubbles covering the almost of whole area of heating
surface. (Fig. 4(a)) From Fig. 4(a’) which shows zoomed
pictures of Fig. 4(a), one can find that the liquid-solid contact
actively remains near the edge of the heating region because of
the existence of nucleate boiling.5) Then, we assume that there
might be two regions on the heating surface with different
boiling regimes. In this study, we take note of temperature
distribution of the heating surface in the MEB region.

1) J. Kim, J. F Benton and D. Wisriewski: Int. J. Heat Mass
Trans., 45, 19 (2002) 3919
2) S. Inada, Y. Miyasaka, S. Sakamoto andChandratilleke: J. Heat Trans., 108, 1 (1986) 219.

G.

R.

3) S. Kumagai, R. Kubo and T. Kawasaki: Heat Transfer-Asian
Research, 32, 2 (2003) 130.
4) G. Wang and P. Cheng: Int. J. Heat Mass Trans., 52 (2009)79.
5) T. Saiki, T. Osawa, I. Ueno and C. Hong: Proc. the ASME
2013 Int. Tech. Conf. and Exh. (2013) 1－93－