NIST Technical Note 1813

Effect of Concentration on 

R134a/Al2O3 Nanolubricant Mixture 

Boiling on a Reentrant Cavity 

Surface with Extensive Measurement 

and Analysis Details

Mark A. Kedzierski
NIST Technical Note 1813

Effect of Concentration on R134a/Al2O3 

Nanolubricant Mixture Boiling on a 

Reentrant Cavity Surface with 

Extensive Measurement and Analysis 

Details

Mark A. Kedzierski

Energy and Environment Division

Engineering Laboratory

September 2013

U.S. Department of Commerce 

Penny Pritzker, Secretary

National Institute of Standards and Technology 

Patrick D. Gallagher, Under Secretary of Commerce for Standards and Technology and Director 
Certain commercial entities, equipment, or materials may be identified in this

document in order to describe an experimental procedure or concept adequately.

Such identification is not intended to imply recommendation or endorsement by the

National Institute of Standards and Technology, nor is it intended to imply that the

entities, materials, or equipment are necessarily the best available for the purpose. 

National Institute of Standards and Technology Technical Note 1813

Natl. Inst. Stand. Technol. Tech. Note 1813, 51 pages (September 2013) 

CODEN: NTNOEF
iii

Effect of Concentration on R134a/Al2O3 Nanolubricant Mixture 

Boiling on a Reentrant Cavity Surface with Extensive Measurement 

and Analysis Details

M. A. Kedzierski

National Institute of Standards and Technology

Bldg. 226, Rm B114

Gaithersburg, MD 20899

Phone: (301) 975-5282

Mark.Kedzierski@NIST.gov

ABSTRACT

This paper quantifies the influence of Al2O3 nanoparticles on the pool boiling performance of 

R134a/polyolester mixtures on a Turbo-BII-HP boiling surface. Nanolubricants with 10 nm 

diameter Al2O3 nanoparticles of various volume fractions (1.6 %, 2.3 %, and 5.1 %) in the 

base polyolester lubricant were mixed with R134a at two different mass fractions (0.5 % and 

1 %). The study showed that nanolubricants can improve R134a boiling on a reentrant cavity 

surface as long as the nanoparticles remain well dispersed in the lubricant and are at 

sufficiently large concentration. For example, three of the refrigerant/nanolubricant mixtures 

with the smallest nanoparticle mass fraction exhibited average enhancements over the entire 

heat flux range of approximately 10 %. However, when the nanoparticle mass fraction was 

increased to a point that likely encouraged agglomeration, an average heat transfer 

degradation of approximately 14 % resulted. An expression for the nanoparticle surface 

density was developed for the Turbo-BII-HP surface for use in an existing model for 

predicting refrigerant/nanolubricant boiling. For heat fluxes greater than 35 kWm-2, the 

model was within 0.5 %, 21 %, and 16 % of the measured heat flux ratios for mixtures with

increasing nanoparticle surface density, respectively. The correspondence between the

increases in the model deviation with the increase in nanoparticle surface density may be due 

to the increased propensity for agglomeration at greater nanoparticle surface density. 

Keywords: additives, aluminum oxide, boiling, enhanced heat transfer, nanolubricant, 

nanotechnology, refrigerants, refrigerant/lubricant mixtures, structured surface
iv

TABLE OF CONTENTS

ABSTRACT............................................................................................................................iii

TABLE OF CONTENTS ...................................................................................................... iv

LIST OF FIGURES............................................................................................................... iv

LIST OF TABLES.................................................................................................................. v

INTRODUCTION................................................................................................................... 1

TEST FLUIDS......................................................................................................................... 2

APPARATUS .......................................................................................................................... 3

TEST SURFACE .................................................................................................................... 3

MEASUREMENTS AND UNCERTAINTIES .................................................................... 3

EXPERIMENTAL RESULTS............................................................................................... 4

DISCUSSION/MODEL DEVELOPMENT.......................................................................... 7

CONCLUSIONS ..................................................................................................................... 9

ACKNOWLEDGEMENTS ................................................................................................. 10

NOMENCLATURE.............................................................................................................. 11

REFERENCES...................................................................................................................... 12

APPENDIX A: UNCERTAINTIES .................................................................................... 44

LIST OF FIGURES

Fig. 1 Schematic of test apparatus...................................................................................... 33

Fig. 2 OFHC copper flat test plate with Turbo-BII-HP surface and thermocouple 

coordinate system...................................................................................................... 34

Fig. 3 Photograph of Turbo-BII-HP surface ..................................................................... 35

Fig. 4 TEM of Al2O3 nanolubricant (Sarkas, 2009).......................................................... 36

Fig. 5 Pure R134a boiling curve for Turbo-BII-HP.......................................................... 37

Fig. 6 R134a/RL68H mixtures boiling curves for Turbo-BII-HP ................................... 38

Fig. 7 Boiling heat flux of R134a/RL68H mixture relative to that of pure R134a for 

Turbo-BII-HP............................................................................................................ 39

Fig. 8 R134a/RL68AlO mixtures boiling curves for Turbo-BII-HP ............................... 40

Fig. 9 Boiling heat flux of R134a/nanolubricant mixtures relative to that of 

R134a/RL68H without nanoparticles for Turbo-BII-HP...................................... 41

Fig. 10 Absolute number of nanoparticles determines average heat transfer 

enhancement for three different surfaces............................................................... 42

Fig. 11 Comparison of predicted to measured heat flux ratio for four different 

refrigerant/nanolubricant mixtures boiling on a Turbo-BII-HP ......................... 43

Fig. A.1 Expanded relative uncertainty in the heat flux of the surface at the 95 % 

confidence level.......................................................................................................... 44

Fig. A.2 Expanded uncertainty in the temperature of the surface at the 95 % confidence 

level............................................................................................................................. 45
v

LIST OF TABLES

Table 1 Conduction model choice....................................................................................... 14

Table 2 Pool boiling data..................................................................................................... 15

Table 3 Number of test days and data points.................................................................... 29

Table 4 Estimated parameters for cubic boiling curve fits for Turbo-BII-HP copper 

surface ........................................................................................................................ 30

Table 5 Residual standard deviation of ∆Ts ...................................................................... 31

Table 6 Average magnitude of 95 % multi-use confidence interval for mean Tw -Ts (K)

..................................................................................................................................... 32
1

INTRODUCTION

Recent advances in nanofluids research have demonstrated the potential for using nanofluids 

in heat transfer equipment to enhance its efficiency and/or performance. An advantage of 

nanofluids is that nanoparticle materials can be very inexpensive and the technology for 

producing nanofluids is mature, especially for viscous liquids. In general, viscous liquids 

produce stable nanofluids due to low settling velocities. Despite this, both Wu et al. (2008)

and Park and Jung (2007) have observed significant boiling enhancements by adding 

nanoparticles to a fluid with a relatively low viscosity, i.e., a refrigerant. As one would 

expect, without constant mixing, the probability of nanoparticle settling is greater for a low 

viscosity fluid than for a fluid with a large viscosity. Accordingly, Wu et al. (2008),

Trisaksri and Wongwises (2009), and Das et al. (2003) attributed the boiling degradations 

with nanoparticles that they observed, for low viscosity fluids like refrigerants and water, to 

nanoparticle deposition on the boiling surface. For this reason, lubricants with dispersed 

nanoparticles, i.e., nanolubricants, can offer the possibility of improving the suspension of 

the nanoparticles due to the favorable viscosity of lubricants. In addition, the lubrication of 

friction surfaces can be improved (Lee et al., 2009) like those that exist in air-conditioning 

compressor with the use of nanolubricants. 

Studies by Henderson et al. (2010), Bi et al. (2007a), Peng et al. (2011), Hu (2013), and 

Kedzierski (2008) have explored the use of nanolubricants as a means for improving 

efficiencies of air-conditioning and refrigeration equipment. For low flow qualities, 

Henderson et al. (2010) have shown that CuO nanoparticles can improve the flow boiling 

heat transfer of refrigerant/lubricant mixtures by as much as 76 % and that the lubricant can 

act as a necessary dispersant. Peng et al. (2010) have shown that diamond nanolubricants 

can improve refrigerant/lubricant pool boiling by as much as 63 %. Similarly, Copper-oxide 

nanoparticles have also been shown to improve refrigerant/lubricant pool boiling by as much 

as 245 % (Kedzierski and Gong, 2009). The key to the boiling enhancement for refrigerants 

as caused by nanolubricants is that the nanoparticles inhabit the viscous lubricant excess 

layer that covers evaporator surface and stably interact with nucleating bubbles to cause

enhanced bubble growth (Kedzierski, 2009). In addition, the combined effects of 

nanoparticles on heat transfer and compressor performance were illustrated by Bi et al. 

(2007b) when they showed that nanolubricants produced energy savings of more than 25 % 

in domestic refrigerators. Aluminum-oxide nanoparticles have produced similar 

enhancements for refrigerant/lubricant boiling (Kedzierski, 2011, 2012a). These preceding 

studies suggest that it is worthwhile to investigate the potential benefits of nanolubricants for 

large commercial chillers. 

Kedzierski (2001a) has shown that the lubricant viscosity and density influence the 

performance of boiling refrigerant/nanolubricant mixtures and are required parameters for its 

prediction (Kedzierski, 2012a). Because of works like Eastman et al. (2001), nanofluids 

immediately bring to mind the benefits of increased thermal conductivity as induced by the 

nanoparticles. However, when considering refrigerant/nanolubricant boiling, the 

improvement associated with increased thermal conductivity is generally less than 20 % of 

the total boiling enhancement (Kedzierski, 2008). Most of the enhancement is caused by an 

exchange of momentum between the nanoparticles and the bubbles (Kedzierski, 2011, 

2012a). 
2

The pool boiling heat transfer model that was developed in Kedzierski (2012a) showed that 

the heat transfer depends on, among other things, the nanoparticle surface density in the 

lubricant excess layer that exists on the boiling surface (Kedzierski, 2012a). In fact, if the 

nanoparticle concentration is less than a critical value, boiling heat transfer can be degraded 

because there are insufficient numbers of nanoparticles remaining in the lubricant excess 

layer to interact with bubbles (Kedzierski, 2009). Likewise, the boiling enhancement with 

nanolubricants is surface dependent given that a similar study showed that the same 

nanolubricant caused on average a 12 % boiling heat transfer degradation on a surface with 

reentrant cavities (Kedzierski, 2012b). 

Consequently, the purpose of the present investigation was to determine if the performance 

of reentrant cavity type surfaces, like the Turbo-BII-HP, could be enhanced with sufficiently 

concentrated nanolubricants and, if so, would the enhancement follow the 

refrigerant/nanolubricant boiling theory developed in Kedzierski (2012a). To achieve this, 

boiling tests of four R134a/nanolubricant mixtures with various nanoparticle concentrations

in the nanolubricant were made on a horizontal, flat, copper, Turbo-BII-HP-finned surface. 

A commercial polyolester lubricant (RL68H)1 with a nominal kinematic viscosity of 

72.3 μm

2

/s at 313.15 K was the base lubricant that was mixed with nominally 10 nm diameter 

Al2O3 nanoparticles. Al2O3 nanoparticles have the advantages of a well-established, successful 

dispersion technology and being relatively inert with respect to lubricated compressor parts.

TEST FLUIDS

A manufacturer used a proprietary surfactant at a mass of 6.2 % of the mass of the Al2O3 as a 

dispersant for the RL68H/Al2O3 mixture (nanolubricant). The manufacturer made the 

mixture such that approximately 24.7 % of the mass was Al2O3 particles. From this mixture, 

nanolubricants with three different mass fractions of Al2O3 (5.6 %, 8.2 %, and 16.7 %) were 

made by adding neat RL68H and ultrasonically mixing the solution for approximately 24 h. 

The 5.6 %, 8.2 %, and 16.7 % Al2O3 mass fractions in the nanolubricant correspond to 

volume fractions (φ) of 1.6 %, 2.3 %, and 5.1 %, respectively. In this study, the 1.6 %, 

2.3 %, and 5.1 % volume fraction nanolubricants are identified as 1AlO, 2AlO, and 5AlO, 

respectively. 

Boiling tests with refrigerant/nanolubricant mixtures with increasing concentration of 

nanoparticles were designed to determine if increases in the nanoparticle surface density of

the lubricant excess layer, Nnp/As, resulted in boiling enhancements that agreed with the 

model introduced in Kedzierski (2012a). The Nnp/As was calculated assuming that all of the 

nanoparticles charged to the test rig reside uniformly distributed on the heat transfer surface. 

The test mixtures R134a/1AlO (99.5/0.5), R134a/1AlO (99/1), R134a/2AlO (99/1), and 

R134a/5AlO (99/1) had nanoparticle surface densities of approximately 2.0 x 1019 m-2

,

4.0 x 1019 m-2, 6.8 x 1019 m-2, and 2.8 x 1020 m-2, respectively. The order of magnitude 

variation in Nnp/As was intended to test the limits of the boiling model. Both the R134a/2AlO 

and the R134a/5AlO mixtures were tested at only 1 % nanolubricant mass fractions. In 

addition, the boiling heat transfer of two R134a/RL68H mixtures (0.5 %, and 1 % mass 

fractions), without nanoparticles, was measured to serve as a baseline for comparison to the 

nanolubricant mixtures. 
3

APPARATUS

Figure 1 shows a schematic of the apparatus that was used to measure the pool boiling data 

of this study. More specifically, the apparatus was used to measure the liquid saturation 

temperature (Ts), the average pool-boiling heat flux (q"), and the wall temperature (Tw) of the 

test surface. The three principal components of the apparatus were the test chamber, the 

condenser, and the purger. The internal dimensions of the test chamber were 25.4 mm × 

257 mm × 1.54 m. The test chamber was charged with approximately 7 kg of refrigerant, 

giving a liquid height of approximately 80 mm above the test surface. As shown in Fig. 1, 

the test section was visible through two opposing, flat 150 mm × 200 mm quartz windows. 

The bottom of the test surface was heated with high velocity (2.5 m/s) water flow. The vapor 

produced by liquid boiling on the test surface was condensed by the brine-cooled, shell-andtube condenser and returned as liquid to the pool by gravity. Further details of the test 

apparatus can be found in Kedzierski (2002) and Kedzierski (2001b). 

TEST SURFACE

Figure 2 shows the oxygen-free high-conductivity (OFHC) copper flat test plate used in this 

study. The test plate was machined out of a single piece of OFHC copper by electric 

discharge machining (EDM). The internal fins of a commercial 25 mm (outer-diameter) 

Turbo-BII-HP tube were removed by EDM. The tube was then cut axially, annealed, 

flattened, and soldered onto the top of the test plate. Figure 3 shows a photograph of the fin 

surface. The Turbo-BII-HP has approximately 826 fins per meter (fpm) oriented along the short 

axis of the plate. The overall height and tip-width of a fin are 0.76 mm and 0.36 mm, 

respectively.

MEASUREMENTS AND UNCERTAINTIES

The standard uncertainty is the positive square root of the estimated variance. The individual 

standard uncertainties are combined to obtain the expanded uncertainty (U), which is 

calculated from the law of propagation of uncertainty with a coverage factor. All 

measurement uncertainties are reported at the 95 % confidence level except where specified 

otherwise. For the sake of brevity, only a summary of the basic measurements and 

uncertainties is given below. Complete detail on the heat transfer measurement techniques 

and uncertainties can be found in Kedzierski (2000) and Appendix A, respectively.

A Dynamic Light Scattering (DLS) technique was used to measure the average nanoparticle 

size on a number basis. The diameter of most of the particles (Dnp) was approximately 10 nm 

(10.1 nm ± 1.3 nm) and the particles were well dispersed in the lubricant (Kedzierski, 2010). 

Figure 4 shows a Transmission Electron Microscopy (TEM) image of the nanoparticles as 

taken by Sarkas (2009). The image confirms the good dispersion and shows that the particles 

are spherical with most of them having diameters of approximately 10 nm or less and a few 

having diameters close to 50 nm. 
4

All of the copper-constantan thermocouples and the data acquisition system were calibrated 

against a glass-rod standard platinum resistance thermometer (SPRT) and a reference voltage 

to a residual standard deviation of 0.005 K. Considering the fluctuations in the saturation 

temperature during the test and the standard uncertainties in the calibration, the expanded 

uncertainty of the average saturation temperature was no greater than 0.04 K. Consequently, 

it is believed that the expanded uncertainty of the temperature measurements was less than 

0.1 K. 

Twenty 0.5 mm diameter thermocouples were force fitted into the wells of the side of the test 

plate shown in Fig. 2. The heat flux and the wall temperature were obtained by regressing 

the measured temperature distribution of the block to the governing two-dimensional 

conduction equation (Laplace equation). In other words, rather than using the boundary 

conditions to solve for the interior temperatures, the interior temperatures were used to solve 

for the boundary conditions following a backward stepwise procedure given in Kedzierski 

(1995)1

. As shown in Fig. 2, the origin of the coordinate system was centered on the surface 

with respect to the y-direction at the heat transfer surface. Centering the origin in the ydirection reduced the uncertainty of the wall heat flux and temperature calculations by 

reducing the number of fitted constants involved in these calculations.

Fourier's law and the fitted constants from the Laplace equation were used to calculate the 

average heat flux (q") normal to and evaluated at the heat transfer surface based on its 

projected area. The average wall temperature (Tw) was calculated by integrating the local 

wall temperature (T). The wall superheat was calculated from Tw and the measured 

temperature of the saturated liquid (Ts). Considering this, the relative expanded uncertainty 

in the heat flux (Uq") was greatest at the lowest heat fluxes, approaching 13 % of the 

measurement near 10 kW/m2. In general, the Uq" remained approximately between 3 % and 

7 % for heat fluxes greater than 20 kW/m2

. The average random error in the wall superheat 

(UTw) remained mainly between 0.06 K and 0.10 K with an average value of approximately 

0.07 K. Plots of Uq" and UTw versus heat flux can be found in Appendix A. 

EXPERIMENTAL RESULTS

The heat flux was varied between approximately 10 kW/m2 and 120 kW/m2 to simulate a 

range of possible operating conditions for R134a chillers. All pool-boiling measurements 

were made at 277.6 K saturated conditions. The data were recorded consecutively starting at 

the largest heat flux and descending in intervals of approximately 4 kW/m2

. The descending 

heat flux procedure minimized the possibility of any hysteresis effects on the data, which 

would have made the data sensitive to the initial operating conditions. Table 2 presents the 

measured heat flux and wall superheat for all the data of this study. Table 3 gives the 

number of test days and data points for each fluid. A total of 2544 measurements were made 

over 48 days.

The mixtures were prepared by charging the test chamber (see Fig. 1) with pure R134a to a 

known mass. Next, a measured mass of nanolubricant or lubricant was injected with a 

syringe through a port in the test chamber. The refrigerant/lubricant solution was mixed by 

 1 Table 1 provides functional forms of the Laplace equation that were used in this study in the same way as was 

done in Kedzierski (1995) and in similar studies by this author.
5

flushing pure refrigerant through the same port where the lubricant was injected. All 

compositions were determined from the masses of the charged components and are given on 

a mass fraction basis. The maximum uncertainty of the lubricant mass fraction (xb) 

measurement is approximately 0.02 %, e.g., the range of a 1.0 % mass fraction is between 

0.98 % and 1.02 %. Nominal or target mass compositions are used in the discussion. For 

example, the “actual” mass composition of the RL68H in the R134a/ RL68H (99.5/0.5) 

mixture was 0.50 % ± 0.02 %. Likewise, the RL68H mass fraction for the R134a/ RL68H 

(99/1) mixture was 1.00 % ± 0.02 %. Using the same uncertainties, the nanolubricant mass 

fractions as tested for R134a/1AlO (99.5/0.5), R134a/1AlO (99/1), R134a/2AlO (99/1),

R134a/5AlO (99/1) were 0.50 %, 0.98 %, 1.00 %, and 1.00 %, respectively.

Figure 5 is a plot of the measured heat flux (q") versus the measured wall superheat (Tw -

Ts = ∆Ts) for pure R134a pool boiling on the Turbo-BII-HP at a saturation temperature of 

277.6 K. These measurements serve as a baseline for comparison to the refrigerant/purelubricant measurements. The open triangles represent the measured data while the solid line 

is a cubic best-fit regression or estimated means of the data. Three days of boiling pure 

R134a produced 118 measurements over a period of approximately one week. Three of the 

118 R134a measurements were removed before fitting because they were identified as 

“outliers” based on having both high influence and high leverage (Belsley et al., 1980). The 

data sets for each test fluid presented in this manuscript exhibited a similar number of 

outliers and were regressed in the same manner. Table 4 gives the constants for the cubic 

regression of the superheat versus the heat flux for all of the fluids tested here. The residual 

standard deviation of the regressions – representing the proximity of the data to the mean –

are given in Table 5 and are, on average, approximately 0.07 K. The dashed lines to either 

side of the mean represent the lower and upper 95 % simultaneous (multiple-use) confidence 

intervals for the mean and are, for the most part, concealed by the data symbols. From the 

confidence intervals, the expanded uncertainty of the estimated mean wall superheat was, on 

average, 0.02 K. Table 6 provides the average magnitude of the 95 % multi-use confidence 

interval for the fitted wall superheat for all of the test data.

Long-dashed lines in Fig. 5 compare pure R134a measurements from two other studies to 

those of the present study. First, the R134a pool boiling curve of Chen and Tuzla (1996) on a 

19 mm OD Turbo-BII-HP tube at Ts = 277.6 K depicted as a dashed line is within 0.4 K of 

the mean superheat of the present measurements when compared at the same heat flux. 

Second, the R134a boiling on a Turbo-BII-HP surface taken in the same test apparatus

(Kedzierski, 2012b) as the present study is shown as a dashed line that crosses the present 

measured mean at a superheat of approximately 3.7 K. Overall, the Kedzierski (2012b) 

boiling curve is within 0.6 K of the mean superheat of the present measurements. It is 

believed that the above comparisons validate the present measurements. 

Figure 6 is a plot of the measured heat flux (q") versus the measured wall superheat (Tw - Ts) 

for the refrigerant/pure-lubricant mixtures at a saturation temperature of 277.6 K. The 

refrigerant/pure-lubricant measurements serve as the baseline for comparison to the 

refrigerant/nanolubricant pool boiling measurements. Thirteen boiling curves were measured

over the span of approximately three weeks. The open circles and squares represent the 

measured heat flux (q") versus the measured wall superheat (Tw - Ts) at a saturation 
6

temperature of 277.6 K for the R134a/RL68H (99.5/0.5) and the R134a/RL68H (99/1) 

mixtures, respectively. From the 95 % multi-use confidence intervals, the expanded 

uncertainty of the estimated mean wall superheat was, on average, 0.01 K.

A general overview of the effect that the pure lubricant mass fraction has on R134a/lubricant 

pool boiling on the Turbo-BII-HP can be obtained from Fig. 6. Comparison of the mean 

boiling curves for R134a/RL68H (99.5/0.5) and R134a/RL68H (99/1) shows that the 

superheats are within 0.5 K of each other for the entire tested heat flux with the heat transfer 

of the (99.5/0.5) mixture being greater than that of the (99/1) mixture for the same superheat. 

The superheat for the R134a/RL68H (99.5/0.5) mixtures is roughly 0.1 K greater and 0.4 K 

greater than that for pure R134a at 30 kW/m2 and 107 kW/m2

, respectively. Addition of 

lubricant to pure R134a has caused a degradation in the boiling heat transfer of R134a. 

Kedzierski (2001a) has shown that, in general, degradations associated with increased 

lubricant mass fractions occur when the concentration-induced bubble size reduction, and its 

accompanying loss of vapor generation per bubble, is not compensated by an increase in site 

density. Typically, heat transfer degradations have been observed to increase with respect to 

increasing lubricant mass fraction. The present measurements are consistent with this heat 

transfer performance trend where the (99.5/0.5) mixture provides a better boiling 

performance than that of the (99/1) mixture. 

A more precise comparison of the R134a/RL68H heat transfer performances relative to pure 

R134a is given in Fig. 7. Figure 7 plots the ratio of the R134a/RL68H mixture heat flux to 

the pure R134a heat flux (q"PL/q"p) versus the pure R134a heat flux (q"p) at the same wall 

superheat. Figure 7 illustrates the influence of lubricant mass fraction on the R134a/RL68H 

boiling curve with solid and dashed lines representing the mean heat flux ratios for each 

mixture and shaded regions showing the 95 % multi-use confidence level for each mean. A 

heat transfer degradation exists where the heat flux ratio is less than one and the 95 % 

simultaneous confidence intervals (depicted by the shaded regions) do not include the value 

one. Figure 7 shows that a boiling heat transfer degradation exists for the entire heat flux 

range for the R134a/RL68H (99/1) mixture. Likewise, the R134a/RL68H (99.5/0.5) exhibits 

a heat transfer degradation for heat fluxes greater than 40 kW/m2. For heat fluxes less than 

40 kW/m2

, it cannot be stated that the boiling heat transfer for the (99.5/0.5) mixture differs 

from that of pure R134a. The heat flux ratio is relatively constant but decreased marginally 

with respect to increasing q"p. More specifically, the q"PL/q"p for the (99/1) mixture 

decreased from approximately 0.89 to 0.83 and that for the (99.5/0.5) mixture decreased from 

0.98 to 0.91 for an increase in q"p from 30 kW/m2 to110 kW/m2

. The average measured heat 

flux ratio (q"PL/q"p), between roughly 30 kW/m2 and 110 kW/m2, was approximately 

0.95 ± 0.01 and 0.85 ± 0.01 for the (99.5/0.5) and the (99/1) mixture, respectively. 

Figure 8 shows the measured heat flux (q") versus the measured wall superheat (Tw - Ts) for 

four mixtures of R134a and three different nanolubricants at a saturation temperature of 

277.6 K. Thirty-two boiling curves were measured over the span of approximately three

months. The closed circles, squares, diamonds, and triangles represent the measurements for 

the R134a/1AlO (99.5/0.5), R134a/1AlO (99/1), R134a/2AlO (99/1), and R134a/5AlO (99/1) 

mixtures, respectively. From the 95 % multi-use confidence intervals, the expanded 

uncertainty of the estimated mean wall superheat was, on average, 0.02 K. 
7

Figure 8 shows three groups of boiling curves with similar heat transfer performance within 

the group: one for the 1AlO (99/1) and 2AlO (99/1) mixtures, which is in the middle of a 

group to its left (1AlO, 99.5/0.5) and one to its right (5AlO, 99/1). The boiling curve for the 

1AlO (99.5/0.5) mixture exhibits the best heat transfer having a heat flux that is roughly 5 % 

greater than that for pure R134a and approximately 10 % greater than that for 

refrigerant/RL68H (99.5/0.5) without nanoparticles (shown in Fig. 6). However, the boiling 

performance decreases for larger nanoparticle surface density. For example, the boiling 

curves for the 1AlO (99/1) and 2AlO (99/1) mixtures, having a Nnp/As 95 % larger and 231 % 

larger than that of 1AlO (99.5/0.5), respectively, have heat fluxes that are approximately 

10 % less than that of 1AlO (99.5/0.5) for the same superheat. Further increase in Nnp/As to 

more than 10 times that of 1AlO (99.5/0.5) resulted in heat fluxes that were roughly 30 % 

less than that of 1AlO (99.5/0.5). 

Figure 9 summarizes the influence of Al2O3 nanoparticles on R134a/RL68H boiling heat 

transfer. The figure plots the ratio of the R134a/RL68H/Al2O3 nanoparticles heat flux to the 

R134a/RL68H heat flux (q"Al/q"PL) versus the R134a/RL68H mixture heat flux (q"PL) at the 

same wall superheat and lubricant mass fraction for the Turbo-BII-HP. Figure 9 presents the 

same measurements of the means for the same mixtures that were presented in Fig. 8 as solid 

lines where each R134a/nanolubricant mixture is compared to the mean of the R134a/purelubricant mixture at the same mass fraction. The maximum heat flux ratio for the 

R134a/1AlO (99.5/0.5) mixture was 1.16 ± 0.02 at a heat flux of 16.5 kW/m2. The heat flux 

ratio, for this mixture, averaged from 10 kW/m2 and 100 kW/m2 was approximately 1.13. 

The maximum heat flux ratio for the R134a/1AlO (99/1) mixture was 1.13 ± 0.01 at a heat 

flux of 33.3 kW/m2. The heat flux ratio, for this mixture, averaged from 10 kW/m2 and 

100 kW/m2 was approximately 1.10. The maximum heat flux ratio for the R134a/2AlO 

(99/1) mixture was 1.11 ± 0.01 at a heat flux of 28.8 kW/m2

. The heat flux ratio, for this 

mixture, averaged from 10 kW/m2 and 100 kW/m2 was approximately 1.09. The maximum 

heat flux ratio for the R134a/5AlO (99/1) mixture was 0.87 ± 0.02 at a heat flux of 

26 kW/m2. The heat flux ratio, for this mixture, averaged from 10 kW/m2 and 100 kW/m2

was approximately 0.86. 

DISCUSSION/MODEL DEVELOPMENT

Recall that the purpose of this study was to determine if the performance of reentrant cavity 

type surfaces could be enhanced with nanolubricants and, if so, would the enhancement 

follow the refrigerant/nanolubricant boiling theory developed in Kedzierski (2012a). One of 

the principles of the refrigerant/nanolubricant boiling theory is shown in Fig. 10, taken from 

Kedzierski (2012a), which illustrates that the absolute number of nanoparticles that are 

suspended in the lubricant excess layer of the boiling surface is a key determinant for the 

boiling enhancement. Figure 10 provides the heat flux ratio averaged between a PL

" q of 

20 kW/m2 and 40 kW/m2 as a function of Nnp/As for three different boiling surfaces.

Measurements for the present study have been added to Fig. 10 using the star symbol. The 

point of Fig. 10 is that despite the variation in nanoparticle volume fraction, 

refrigerant/nanolubricant mass fraction, and the boiling surface geometry, the boiling 

enhancement follows the general trend of increasing with respect to nanoparticle surface 

density. 
8

Comparison of the present measurements to the mean of the Fig. 10 data is not entirely 

conclusive. If only the measurements with the three lowest values of Nnp/As are considered, 

then the largest deviation from the 95 % confidence interval of the mean is roughly 0.01, 

while the measurement for the third largest Nnp/As is within the confidence interval. These 

three data points are neither strong confirmation nor sufficient condemnation of the theory. 

However, the measurement for the largest Nnp/As is approximately 31 % less than the mean of 

Fig. 10. This would be supportive evidence to at least begin to question the theory that 

Nnp/As governs the boiling enhancement had there not been significant nanoparticle 

agglomeration observed during boiling. Consequently, the heat transfer degradation with 

respect to increase in Nnp/As, for the case of largest Nnp/As, is attributed to the observed 

nanoparticle agglomeration. Agglomeration causes loss of nucleation sites by filling the 

boiling cavities with nanoparticles and in addition, agglomeration prevents the nanoparticles 

from becoming part of the lubricant excess layer where they interact with bubbles to induce 

an enhancement (Kedzierski, 2012c). An attempt was made during testing to remedy this by 

attaching an acoustic transducer to the side of the test chamber above the boiling surface; 

however, visible agglomerated nanoparticles persisted. As a result, these tests are not 

adequate to prove or disprove the theory that continued increase in the absolute number of 

nanoparticles in the nanolubricant improves the boiling. 

Equation 1 gives the boiling heat transfer model for refrigerant/aluminum oxide 

nanolubricant mixtures valid for a plain surface and a rectangular-finned surface as a 

function of surface geometry dependent nanoparticle surface density; (Nnp/As)G (Kedzierski, 

2012c):

( ) ( )

9 1 np

" L vb

np s G

" 3/2 " 2

PL np n L np L b

1.45 10 [s m ]

1

(1 )

N

x

q A

q D q g x

σν ρ

ρρ ρ

− − × ⋅

= +

− −

(1)

where "

n q is equal to "PL q normalized by 1 Wm-2 . Properties included in eq. (1) are the 

refrigerant surface tension (σ), the refrigerant vapor density (ρv), the neat lubricant liquid 

density (ρL) and liquid kinematic viscosity (νL), and the nanoparticle density (ρnp).

The model above is based on the assumption that the enhancement is due to surface work on 

bubbles as caused by momentum transfer between growing bubbles and nanoparticles 

suspended within the lubricant excess layer. Equation 1 is a function of the surface geometry 

dependent nanoparticle surface density: (Nnp/As)G. For the smooth surface, (Nnp/As)G is equal 

to Nnp/As. The Nnp/As is obtained by calculating the entire active surface area of the 

evaporator (As) and dividing it into the total number of nanoparticles (Nnp) charged to the 

evaporator, which can be obtained by assuming a spherical particle diameter of an average 

size. 

The expression for (Nnp/As)G that, when substituted into eq. (1), makes it valid for the 

rectangular fin surface is a function of the normalized pure lubricant heat flux ( n

" q ) and 

Nnp/As (Kedzierski, 2012c):
9

( )

1.47

2.53 np 8 " np 20

n

s s G

4.15 10 1 10

N N

q A A

−  

= ×   ⋅ ×

 

(2)

The leading constant includes the surface geometry effects for the 826 fins per meter (fpm) 

rectangular-finned surface with overall fin-height and fin-tip-width of 0.76 mm and 0.36 mm, 

respectively. A crude modification of eq. (2) to make it valid for the 1AlO (99.5/0.5) mixture 

boiling on the Turbo-BII-HP is done so by adding an additional term to account for the 

additional surface area of the Turbo-BII-HP and the greater effectiveness of the surface as 

compared to the rectangular-finned surface:

( )

1.47

2.53 np 8 " np 20 "

n n

s s G

4.15 10 1 10 0.00017

N N

q q A A

−  

= ×   ⋅× +

 

(3)

The additional term is a function of the normalized heat flux to account for the increased 

interaction between bubble and nanoparticles with increase in heat flux as more of the 

surface becomes active with bubble nucleation. This term was determined from regressing 

with the measured 1AlO (99.5/0.5) heat flux ratio. The other mixtures were not used in the 

regression because full dispersion of the nanoparticles was not certain.

Figure 11 shows the predictions of eq. (1) while using the expression for (Nnp/As)G for the 

Turbo-BII-HP fin as given by eq. (3). Predictions using eq. (1) together with eq. (3) were 

done for three of the four refrigerant/nanolubricant mixtures of the study over the entire test 

heat flux range. The 5AlO (99/1) mixture was not included in the prediction because the 

nanoparticles were not well dispersed in the lubricant excess layer. For heat fluxes greater

than 35 kWm-2, the predictions for the 1AlO (99.5/0.5) mixture are within 0.5 % of the 

measured means. For heat fluxes less than 35 kWm-2

, the 1AlO (99.5/0.5) mixture 

predictions are on average 4 % greater than the measured means. For heat fluxes greater than 

35 kWm-2

, the 1AlO (99/1) mixture and the 2AlO (99/1) mixture are overpredicted by, on 

average, 21 % and 16 %, respectively. It is possible that particle agglomeration may have 

reduced the nanoparticle surface density contributing to the overprediction of the 1AlO 

(99/1) and the 2AlO (99/1) mixtures. 

Future research is required to devise a method to measure the quality of the nanoparticle 

dispersion in the lubricant excess layer on a boiling surface. This will permit further 

improvements on the refrigerant/nanolubricant boiling heat transfer model by qualifying data 

that is suitable for analysis. Without a reliable means for qualifying the dispersion in the 

lubricant excess layer, it is not possible to conclusively attribute the boiling heat transfer

degradation of the previous study (Kedzierski, 2012b) and that observed in the present to 

nanoparticle agglomeration. Additional areas for future research are methods for dispersing 

agglomerated nanoparticles in actively boiling fluids, e.g., acoustic excitation.

CONCLUSIONS

The effect of Al2O3 nanoparticles on the boiling performance of R134a/polyolester mixtures 

on a flattened, horizontal Turbo-BII-HP was investigated. Nanolubricants containing 

roughly 10 nm diameter Al2O3 nanoparticles of various volume fractions with a polyolester 

lubricant was mixed with R134a at two different mass fractions. The study showed that 
10

nanolubricants can improve R134a boiling on a Turbo-BII-HP, thus demonstrating that the 

boiling performance of reentrant cavity surfaces can be enhanced if a sufficient nanoparticle 

surface density is achieved. For example, the R134a/1Al0 (99.5/0.5), R134a/1Al0 (99/1), 

and the R134a/2Al0 (99/1) mixtures exhibited average enhancement of approximately 13 %, 

10 % and 9 %, respectively. Only the R134a/5AlO (99/1) mixture exhibited an average heat 

transfer degradation of approximately 14 % and this was believed to be due to nanoparticle 

agglomeration.

An expression for the nanoparticle surface density was developed for the Turbo-BII-HP 

surface for use in an existing model for predicting refrigerant/nanolubricant boiling. For heat 

fluxes greater than 35 kWm-2

, the model is within 0.5 %, 21 %, and 16 % of the measured 

heat flux ratios for the 1AlO (99.5/0.5), the 1AlO (99/1), and the 2AlO (99/1) mixtures, 

respectively. It is possible that particle agglomeration may have reduced the nanoparticle 

surface density contributing to the deviation of the model from the measurements for the 

1AlO (99/1) and the 2AlO (99/1) mixtures. However, without a reliable means for qualifying 

the dispersion in the lubricant excess layer, it is not possible to conclusively attribute the 

deviation to nanoparticle agglomeration.

ACKNOWLEDGEMENTS

This work was funded by the U.S. Department of Energy (project no. DE-EE0002057/004) 

under Project Manager Antonio Bouza. Thanks go to Dongsoo Jung of Inha University and 

to the following NIST personnel for their constructive criticism of the draft manuscript: A. 

Pertzborn, and P. Domanski. Furthermore, the author extends appreciation to W. Guthrie and 

A. Heckert of the NIST Statistical Engineering Division for their consultations on the 

uncertainty analysis. Boiling heat transfer measurements were taken by D. Wilmering of KT 

Consulting at the NIST laboratory. The RL68H (EMKARATE RL 68H) was donated by K. 

Lilje of CPI Engineering Services, Inc. The RL68H1AlO was manufactured by Nanophase 

Technologies with an aluminum oxide and dispersant in RL68H especially for NIST. 
11

NOMENCLATURE

English Symbols

An regression constant in Table 4 n=0,1,2,3

As heat transfer surface area, m

Dnp nanoparticle diameter, m

g gravitational acceleration, m·s-2

Nnp the number of nanoparticles

Nnp/As nanoparticle surface density, m-2

q" average wall heat flux, W·m-2

"

n q

"

PL

-2 1W m

q = ⋅

T temperature, K

Tw temperature at roughened surface, K

U expanded uncertainty

X model terms given in Table 2

xb bulk lubricant mass fraction

Greek symbols

∆Ts wall superheat: Tw - Ts, K 

ν kinematic viscosity, m2·s-1

σ surface tension of refrigerant, N·m-1

ρ density, kg·m-3

φ nanoparticle volume fraction

English Subscripts

Al R134a/nanolubricant mixture

G surface geometry dependent

L pure lubricant without nanoparticles

nL nanolubricant 

np nanoparticle/with nanoparticles

p pure R134a

PL refrigerant/pure lubricant (R134a/RL68H) mixture

q" heat flux

s saturated state

Tw wall temperature

v refrigerant vapor 
12

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Influential Data and Sources of Collinearity, New York: Wiley.

Bi, S., Shi, L., and Zhang, L., 2007a, “Performance Study of a Domestic Refrigerator Using 

R134a/Mineral Oil/Nano-TiO2 as Working Fluid,” Proceedings of International Conference 

of Refrigeration, Beijing, ICRO7-B2-346.

Bi, S., Shi, L., and Zhang, L., 2007b, “Application of Nanoparticles in Domestic 

Refrigerators,” Applied Thermal Engineering, Vol. 28, pp. 1834-1843.

Chen, J., and Tuzla, K., 1996, "Heat Transfer Characteristics of Alternative Refrigerants; 

Volume 3: Condenser and Evaporator Outside Tube," EPRI TR-106016-V3, project 3412-53, 

Palo Alto.

Das, S. K., Putra, N., and Roetzel, W., 2003, “Pool Boiling Characteristics of Nano Fluids,” 

Int. J. of Heat and Mass Transfer, Vol. 46, No. 5, pp. 4499-4502.

Hu, H., Peng, H., and Ding, G., 2013,”Nucleat Pool Boiling Heat Transfer Characteristics of 

Refrigerant/Nanolubricant Mixture with Surfactant,” Int. J. Refrigeration, Vol. 36, pp. 1045-

1055.

Henderson, K., Park, Y., Liu, L., Jacobi, A. M., 2010, “Flow-Boiling Heat Transfer of R134a-Based Nanofluids in a Horizontal Tube,” IJHMT, 53, 944-951

Kedzierski, M. A., 2012a, “R134a/Al2O3 Nanolubricant Mixture Boiling on a Rectangular 

Finned Surface,” ASME J. Heat Transfer, Vol. 134, 121501.

Kedzierski, M. A., 2012b, “Effect of Al2O3 Nanolubricant on a Turbo-BII R134a Pool 

Boiling Surface,” Proceedings of MNHMT2012 3rd Micro/Nanoscale Heat & Mass Transfer 

International Conference, Atlanta, Georgia, MNHMT2012-75024.

Kedzierski, M. A., 2012c, “Effect of Diamond Nanolubricant on R134a Pool Boiling Heat 

Transfer,” ASME Journal of Heat Transfer, Vol. 134, 051001.

Kedzierski, M. A., 2011, “Effect of Al2O3 Nanolubricant on R134a Pool Boiling Heat 

Transfer,” Int. J. Refrigeration, Vol. 34, pp. 498-508.

Kedzierski, M. A., 2010, “Effect of Al2O3 Nanolubricant on a Passively Enhanced R134a Pool 

Boiling Surface with Extensive Measurement and Analysis Details,” NIST Technical Note 

1677, U.S. Department of Commerce, Washington, D.C.

Kedzierski, M. A., 2009, “Effect of CuO Nanoparticle Concentration on R134a/Lubricant PoolBoiling Heat Transfer," ASME J. Heat Transfer, Vol. 131, No. 4, 043205.
13

Kedzierski, M. A., 2002, “Use of Fluorescence to Measure the Lubricant Excess Surface 

Density During Pool Boiling,” Int. J. Refrigeration, Vol. 25, pp. 1110-1122.

Kedzierski, M. A., 2001a, “The Effect of Lubricant Concentration, Miscibility and Viscosity 

on R134a Pool Boiling” Int. J. Refrigeration, Vol. 24, No. 4., pp. 348-366.

Kedzierski, M. A., 2001b, “Use of Fluorescence to Measure the Lubricant Excess Surface 

Density During Pool Boiling,” NISTIR 6727, U.S. Department of Commerce, Washington, 

D.C.

Kedzierski, M. A., 2000, “Enhancement of R123 Pool Boiling by the Addition of 

Hydrocarbons,” Int. J. Refrigeration, Vol. 23, pp. 89-100.

Kedzierski, M. A., 1995, “Calorimetric and Visual Measurements of R123 Pool Boiling on 

Four Enhanced Surfaces,” NISTIR 5732, U.S. Department of Commerce, Washington. 

Lee, J, Cho, S., Hwang, Y., Cho, H., J., Lee, C., Choi, Y., Ku, B. C., Lee, H., Lee, B., Kim, 

B., and Kim, S. H., 2009, “Application of Fullerene-Added Nano-Oil for Lubrication 

Enhancement in Friction Surfaces,” Tribology Int., Vol. 42, pp. 440-447.

Park, K. J., and Jung, D., 2007, “Enhancement of Nucleate Boiling Heat Transfer Using 

Carbon Nanotubes,” Int. J. of Heat and Mass Transfer, Vol. 50, pp. 4499–4502.

Peng, H., Ding, G., Hu, H., and Jiang, W., 2011, “Effect of Nanoparticle Size on Nucleate 

Pool Boiling Heat Transfer of Refrigerant/oil Mixture with Nanopartilces,” Int. J. Heat and 

Mass Transfer, Vol. 54, pp. 1839-1850.

Peng, H., Ding, G., Hu, H., Jiang, W., Zhuang, D., and Wang, K., 2010, “Nucleate Pool 

Boiling Heat Transfer Characteristics of Refrigerant/oil Mixture with Diamond 

Nanopartilces,” Int. J. Refrigeration, Vol. 33, pp. 347-358.

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R11 with TiO2 Nano-Particles,” J. of Engr. Thermophysics, Vol. 29, No. 1, pp. 124-126.

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Nanofluids,” Int. J. of Heat and Mass Transfer, Vol. 52, No. 5-6, pp. 1582-1588.
14

Table 1 Conduction model choice

X0= constant (all models) X1= x X2= y X3= xy 

X4=x

2

-y

2

X5= y(3x2-y

2

) X6= x(3y2-x

2

) X7= x

4

+y4-6(x2)y2

 X8= yx

3

-xy

3

Fluid Most frequent models

Pure R134a 

(file: TBC134a.dat)

X1,X2,X5 (78 of 118) 66 %

X1,X3 (35 of 118) 30 %

X1,X2,X3 (5 of 118) 4 %

R134a/RL68H (99.5/0.5) 

(file:TBCRL5.dat)

X1,X2,X5 (212 of 212) 100 %

R134a/RL68H (99/1) 

(file: TBCRL1.dat)

X1,X2,X5 (183 of 359) 51 %

X1,X3(176 of 359) 49 %

R134a/1AlO (99.5/0.5) 

(file:TBCAL5.dat)

X1,X2,X5 (197 of 402) 49 %

X1,X3 (143 of 402) 36 %

X1,X2,X5,X7 (5 of 402) 1 %

R134a/1AlO (99/1) 

(file:TBCAL1.dat)

X1,X3 (215 of 420) 51 %

X1,X2,X5 (207 of 420) 49 %

R134a/2AlO (99/1) 

(file:TBCAL81.dat)

X1,X3 (403 of 749) 54 %

X1,X2,X5 (320 of 749) 43 %

X1,X2,X5,X6 (14 of 749) 2 %

X1,X2,X5,X7 (6 of 749) 1 %

R134a/5AlO (99/1) 

(file:TBCAL17.dat)

X1,X3 (169 of 284) 59 %

X1,X3,X5 (86 of 284) 30 %

X1,X2,X3 (13 of 284) 5 %

X1, X5 (9 of 284) 3 %
15

Table 2 Pool boiling data

Pure R134a

File: TBC134a.dat ∆Ts

(K)

q" 

(W/m

2

)

 5.47 113890.

 5.45 113469.

 5.45 113573.

 5.07 104758.

 5.04 104284.

 5.03 104384.

 4.79 98357.

 4.79 98549.

 4.78 98543.

 4.51 92472.

 4.52 92483.

 4.50 92444.

 4.25 86906.

 4.22 86515.

 4.21 86056.

 3.89 79357.

 3.89 79362.

 3.88 79346.

 3.61 73831.

 3.61 73786.

 3.61 73674.

 3.33 67806.

 3.32 67511.

 3.31 67515.

 3.01 61569.

 3.00 61581.

 3.01 61533.

 2.72 56030.

 2.71 56071.

 4.87 107861.

 4.87 108085.

 4.89 108259.

 4.66 101618.

 4.66 101654.

 4.66 101616.

 4.43 95485.

 4.42 95600.

 4.43 95632.

 4.20 89740.

 4.20 89792.

 4.20 89814.

 3.97 83809.

 3.96 83730.

 3.96 83961.

 3.72 78183.

 3.71 78004.

 3.71 77833.

 3.47 72487.

 3.47 72676.

 3.48 72516.

 3.20 66597.

 3.21 66634.

 3.20 66627.

 2.95 61231.

 2.95 61327.

 2.96 61430.

 2.71 56023.

 2.71 56165.

 2.71 56124.

 2.44 50586.

 2.45 50535.

 2.44 50516.

 2.18 45849.

 2.18 45896.

 2.19 45915.

 1.95 40610.

 1.94 40427.

 1.94 40434.

 1.70 36158.

 1.70 36151.

 1.71 36131.

 1.50 31930.

 1.50 31873.

 4.91 107889.

 4.94 108234.

 4.94 108065.

 4.74 101100.

 4.75 101029.

 4.73 100946.

 4.54 94962.

 4.54 95017.

 4.54 95106.

 4.33 88860.

 4.32 88948.

 4.32 88881.

 4.10 82930.

 4.10 83246.

 4.10 83385.

 3.87 76934.

 3.86 77002.

 3.85 77039.

 3.63 71510.

 3.63 71586.

 3.63 71657.

 3.39 65868.

 3.37 65929.

 3.38 65997.

 3.14 60284.

 3.13 60223.

 3.12 60088.

 2.87 55065.

 2.88 55120.

 2.87 55190.

 2.62 49935.

 2.61 50000.

 2.63 50165.

 2.36 44966.

 2.35 45047.

 2.36 45187.

 2.11 39795.

 2.09 39894.

 2.10 39937.

 1.85 35629.

 1.86 35656.

 1.86 35670.

 1.63 31114.

 1.62 31189.

 1.62 31336.

R134a/RL68H (99.5/0.5)

File: TBCRL5.dat ∆Ts

(K)

q" 

(W/m

2

)

 5.61 110211.

 5.60 110303.

 5.59 110288.

 5.30 104266.

 5.31 104294.

 5.30 104360.

 5.03 98862.

 5.03 98970.

 5.03 99076.

 4.73 92785.

 4.73 92930.

 4.74 93036.

 4.46 87238.

 4.46 87251.

 4.45 87327.

 4.16 81376.

 4.16 81459.

 4.16 81582.

 3.88 75951.

 3.87 75959.

 3.88 76016.

 3.61 70214.

 3.61 70277.

 3.59 70162.

 3.33 64984.

 3.33 65095.

 3.34 65161.

 3.07 59592.

 3.06 59566.

 3.06 59540.

 2.78 53941.

 2.78 53968.

 2.77 53912.

 2.52 48599.

 2.52 48596.

 2.51 48491.

 2.23 43456.

 2.24 43477.

 5.60 110597.

 5.59 110287.

 5.58 110300.

 5.29 104045.

 5.29 104131.

 5.30 104271.

 5.04 98773.

 5.03 98589.

 5.04 98600.

 4.75 92634.

 4.74 92648.

 4.74 92658.

 4.46 86981.

 4.46 87112.

 4.47 87101.

 4.17 80958.

 4.17 80941.

 4.16 80931.

 3.90 75410.

 3.90 75484.

 3.90 75557.
16

 3.62 69911.

 3.63 69990.

 3.62 70047.

 3.35 64444.

 3.35 64376.

 3.35 64272.

 3.07 58812.

 3.07 58930.

 3.07 59011.

 2.82 53698.

 2.81 53636.

 2.81 53665.

 2.54 48399.

 2.54 48391.

 2.55 48442.

 2.27 42990.

 2.26 42945.

 2.26 42947.

 1.98 38367.

 1.99 38328.

 1.99 38377.

 1.75 34065.

 1.75 33963.

 5.51 110725.

 5.50 110884.

 5.51 110995.

 5.22 104593.

 5.23 104747.

 5.23 104820.

 4.95 98624.

 4.96 98811.

 4.96 98822.

 4.69 92809.

 4.68 92838.

 4.68 92799.

 4.41 86946.

 4.42 86956.

 4.41 87031.

 4.14 81560.

 4.14 81649.

 4.16 81959.

 3.89 75757.

 3.87 75765.

 3.88 75696.

 3.61 70035.

 3.61 70103.

 3.60 70075.

 3.34 64531.

 3.34 64558.

 3.34 64546.

 3.07 59076.

 3.07 59122.

 3.07 59114.

 2.79 53640.

 2.78 53524.

 2.79 53671.

 2.53 48396.

 2.53 48417.

 2.54 48434.

 2.26 43234.

 2.25 43141.

 2.26 43205.

 1.99 38444.

 1.99 38351.

 1.99 38384.

 1.75 33996.

 1.74 33919.

 5.50 111168.

 5.51 111350.

 5.52 110988.

 5.22 104612.

 5.23 104758.

 5.23 104761.

 4.96 98676.

 4.96 98643.

 4.97 98675.

 4.70 92915.

 4.69 93003.

 4.70 93038.

 4.42 86873.

 4.42 86933.

 4.42 86934.

 4.14 81343.

 4.14 81457.

 4.15 81360.

 3.87 76301.

 3.88 75909.

 3.88 75640.

 3.59 70343.

 3.60 70376.

 3.60 70466.

 3.33 64626.

 3.33 64651.

 3.33 64558.

 3.07 59346.

 3.07 59399.

 3.08 59439.

 2.80 53636.

 2.79 53628.

 2.79 53521.

 2.53 48597.

 2.53 48714.

 2.53 48636.

 2.26 43213.

 2.26 43281.

 2.27 43451.

 1.98 38385.

 1.98 38437.

 1.98 38362.

 1.75 33968.

 1.73 33814.

 5.47 110181.

 5.46 110199.

 5.47 110247.

 5.17 103591.

 5.17 103608.

 5.16 103567.

 4.89 98019.

 4.89 98183.

 4.91 98322.

 4.65 92600.

 4.64 92398.

 4.64 92226.

 4.36 86604.

 4.37 86706.

 4.36 86820.

 4.09 80756.

 4.08 80779.

 4.09 80784.

 3.82 75149.

 3.83 75168.

 3.82 75159.

 3.56 69664.

 3.56 69725.

 3.57 69806.

 3.30 64265.

 3.30 64287.

 3.29 64331.

 3.03 58838.

 3.03 58761.

 3.03 58791.

 2.77 53238.

 2.72 53827.

 2.73 53870.

 2.48 48421.

 2.48 48465.

 2.48 48534.

 2.22 43039.

 2.22 43016.

 2.21 42790.

 1.92 38524.

 1.97 37903.

 1.92 39081.

R134a/RL68H (99/1)

File: TBCRL1.dat ∆Ts

(K)

q" 

(W/m

2

)

 6.06 109296.

 6.02 109216.

 6.02 109132.

 5.75 103148.

 5.75 103276.

 5.75 103308.

 5.48 97240.

 5.32 97963.

 5.34 98178.

 5.08 92496.

 5.08 92507.

 5.09 92485.

 4.79 86756.

 4.79 86589.

 4.80 86703.

 4.55 81412.

 4.55 81508.

 4.54 81249.

 4.25 75239.

 4.24 75157.

 4.24 75093.

 3.92 69159.

 3.92 69231.

 3.92 69578.

 3.65 64214.

 3.66 63966.

 5.89 108675.

 5.89 108818.

 5.89 108944.

 5.60 102414.

 5.59 102495.

 5.59 102803.

 5.29 96926.

 5.30 97271.
17

 5.31 97271.

 5.06 91614.

 5.06 91754.

 5.06 91801.

 4.73 85760.

 4.73 85825.

 4.75 85878.

 4.45 80346.

 4.43 80542.

 4.49 80703.

 4.19 74626.

 4.20 74584.

 4.20 74689.

 3.92 69334.

 3.91 69414.

 3.92 69450.

 3.63 63464.

 3.60 63382.

 3.60 63449.

 3.34 58161.

 3.33 58167.

 3.33 58048.

 3.05 53132.

 3.04 53121.

 3.04 53284.

 2.76 47992.

 2.76 47959.

 2.76 47980.

 2.47 42935.

 2.46 43227.

 2.46 43271.

 2.21 38490.

 2.20 38236.

 2.20 38178.

 1.92 33688.

 1.91 33692.

 5.89 108513.

 5.90 108593.

 5.90 108727.

 5.62 102274.

 5.61 102472.

 5.61 102538.

 5.34 96444.

 5.33 96392.

 5.33 96345.

 5.05 90570.

 5.05 90702.

 5.05 90658.

 4.79 85394.

 4.80 85548.

 4.79 85574.

 4.48 79470.

 4.50 79955.

 4.50 79898.

 4.22 74126.

 4.21 74320.

 4.22 74496.

 3.93 68678.

 3.93 68763.

 3.92 68714.

 3.66 63409.

 3.66 63478.

 3.65 63566.

 3.36 57893.

 3.35 58089.

 3.37 58197.

 3.09 53110.

 3.09 53092.

 3.09 53107.

 2.80 47761.

 2.79 47841.

 2.81 47810.

 2.53 43325.

 2.51 43171.

 2.51 43309.

 2.25 38588.

 2.24 38393.

 2.23 38374.

 1.96 33624.

 1.94 33495.

 1.95 33660.

 1.70 29535.

 1.69 29389.

 5.90 108940.

 5.90 109137.

 5.90 109202.

 5.60 102375.

 5.59 102345.

 5.59 102528.

 5.32 97015.

 5.32 97111.

 5.32 97226.

 5.05 91224.

 5.05 91334.

 5.04 91200.

 4.76 85441.

 4.77 85804.

 4.78 85885.

 4.47 79757.

 4.47 79702.

 4.47 79654.

 4.20 74673.

 4.21 74701.

 4.21 74686.

 3.92 68971.

 3.91 69009.

 3.91 68998.

 3.63 63484.

 3.62 63519.

 3.62 63416.

 3.34 58444.

 3.34 58481.

 3.35 58629.

 3.08 53286.

 3.07 53197.

 3.07 53183.

 2.79 48255.

 2.80 48296.

 2.80 48189.

 2.51 43255.

 2.50 43369.

 2.51 43377.

 2.24 38337.

 2.22 38313.

 2.22 38296.

 1.95 33944.

 1.94 33832.

 1.94 33803.

 1.69 29416.

 1.68 29260.

 5.95 109349.

 5.96 109576.

 5.96 109619.

 5.66 103050.

 5.66 103048.

 5.67 103134.

 5.40 97441.

 5.40 97531.

 5.40 97344.

 5.12 91685.

 5.12 91660.

 5.12 91782.

 4.84 85984.

 4.84 86109.

 4.84 85839.

 4.55 80268.

 4.55 80523.

 4.56 80488.

 4.26 74635.

 4.26 74388.

 4.26 74480.

 3.98 69325.

 3.99 69505.

 3.98 69478.

 3.71 63977.

 3.70 63887.

 3.70 63734.

 3.41 58650.

 3.42 58749.

 3.41 58692.

 3.14 53235.

 3.12 53134.

 3.12 53074.

 2.84 48363.

 2.85 48471.

 2.85 48454.

 2.57 43700.

 2.56 43604.

 2.56 43605.

 2.29 38718.

 2.27 38710.

 2.27 38711.

 2.00 34149.

 1.98 33937.

 5.93 109447.

 5.94 109746.

 5.93 109816.

 5.64 102930.

 5.65 103020.

 5.64 103242.

 5.37 97252.

 5.37 97295.

 5.37 97441.

 5.10 91649.

 5.10 91784.

 5.10 91665.

 4.83 86060.

 4.82 85953.

 4.82 85967.

 4.53 80167.

 4.53 79977.

 4.53 80076.

 4.24 74495.

 4.23 74579.

 4.24 74642.
18

 3.97 68987.

 3.96 69108.

 3.96 69197.

 3.69 63877.

 3.69 63943.

 3.70 64009.

 3.40 58251.

 3.40 58466.

 3.40 58476.

 3.12 53253.

 3.12 53203.

 3.11 53148.

 2.84 48345.

 2.84 48586.

 2.85 48324.

 2.56 43291.

 2.54 43300.

 2.54 43329.

 2.27 38442.

 2.24 38158.

 2.23 38101.

 1.95 33637.

 1.94 33697.

 5.38 96378.

 5.38 96278.

 5.38 96419.

 5.11 90746.

 5.11 90882.

 5.12 90936.

 4.84 85142.

 4.83 85034.

 4.84 85150.

 4.54 79220.

 4.54 79187.

 4.54 79279.

 4.25 74205.

 4.27 74315.

 4.27 74381.

 3.98 68783.

 3.98 68777.

 3.98 68712.

 3.70 63182.

 3.67 63121.

 3.68 62891.

 3.40 58100.

 3.40 57958.

 3.41 57913.

 3.11 53076.

 3.10 52870.

 3.09 52769.

 2.81 47810.

 2.80 47871.

 2.80 47686.

 2.52 42863.

 2.50 42539.

 2.49 42518.

 2.23 38108.

 2.22 38186.

 2.22 38094.

 1.95 33707.

 1.95 33644.

 1.95 33862.

 1.68 29475.

 1.67 29107.

 1.68 29374.

 1.46 25337.

 1.43 25033.

 1.43 24833.

 1.20 21595.

 1.15 21212.

 1.15 21094.

 0.92 17477.

 0.89 17044.

 0.88 16898.

 0.62 13450.

 0.59 13245.

 5.31 96522.

 5.31 96861.

 5.31 96974.

 5.04 90821.

 5.04 90905.

 5.04 91033.

 4.74 85093.

 4.74 85058.

 4.74 85090.

 4.45 79237.

 4.46 79275.

 4.46 79514.

 4.18 73811.

 4.18 73811.

 4.18 73997.

 3.91 68310.

 3.88 68381.

 3.91 68361.

 3.60 62903.

 3.59 62972.

 3.60 63082.

 3.28 57931.

 3.26 58060.

 3.25 58003.

 3.02 52771.

 3.04 52815.

 3.03 52816.

 2.75 48045.

 2.72 48093.

 2.76 48016.

 2.47 42868.

 2.45 42809.

 2.44 42832.

 2.24 38186.

 2.23 38140.

 2.25 38188.

 2.00 33702.

 1.99 33697.

 1.99 33490.

 1.72 29492.

 1.70 29444.

 1.71 29377.

 1.47 25269.

 1.46 24893.

 1.46 25082.

 1.22 21142.

 1.20 20831.

 1.20 20838.

 0.94 17449.

 0.91 16802.

 0.90 16777.

 0.67 13435.

 0.67 13454.

 0.67 13319.

R134a/1ALO(99.5/0.5)

File: TBCAL5.dat ∆Ts

(K)

q" 

(W/m

2

)

 5.24 112950.

 5.25 113082.

 5.26 112719.

 5.00 106344.

 5.01 106490.

 5.02 106595.

 4.76 100085.

 4.76 100379.

 4.77 100060.

 4.49 93887.

 4.48 93916.

 4.48 94102.

 4.23 88118.

 4.22 88124.

 4.22 88287.

 3.97 82391.

 3.97 82412.

 3.97 82395.

 3.68 76695.

 3.69 76746.

 3.68 76776.

 3.42 71525.

 3.42 71641.

 3.43 71588.

 3.18 66145.

 3.18 66158.

 3.18 66092.

 2.93 60792.

 2.92 60685.

 2.91 60654.

 2.67 55431.

 2.66 55479.

 2.65 55339.

 2.42 50461.

 2.42 50260.

 2.40 50082.

 2.16 45068.

 2.15 44934.

 2.15 44982.

 1.91 40256.

 1.89 40070.

 1.91 40155.

 1.65 35261.

 1.65 35198.

 1.65 35130.

 1.42 30934.

 1.40 30753.

 1.41 30674.

 1.18 26240.

 1.18 25891.

 1.17 25773.

 0.96 21924.

 0.94 21648.

 0.94 21525.

 0.73 17657.

 0.71 17379.

 5.36 111708.
19

 5.36 111580.

 5.35 111585.

 5.07 104957.

 5.07 105153.

 5.09 105243.

 4.81 99180.

 4.82 99634.

 4.83 99562.

 4.55 93443.

 4.56 93625.

 4.56 93576.

 4.27 87870.

 4.27 87973.

 4.27 88045.

 3.99 82231.

 3.98 82382.

 3.99 82393.

 3.72 76821.

 3.72 76811.

 3.72 76844.

 3.45 71305.

 3.44 71271.

 3.44 71434.

 3.18 65916.

 3.17 66016.

 3.18 66144.

 2.93 60556.

 2.92 60420.

 2.92 60413.

 2.65 55363.

 2.65 55276.

 2.65 55251.

 2.39 50173.

 2.39 50001.

 2.38 50061.

 2.15 45507.

 2.15 45395.

 2.15 45193.

 1.90 40090.

 1.89 39926.

 1.89 39858.

 1.63 35018.

 1.62 34934.

 1.62 34970.

 1.39 30882.

 1.40 30827.

 1.40 30822.

 1.16 26290.

 1.16 25956.

 1.15 25911.

 0.95 22094.

 0.92 21689.

 0.92 21621.

 0.71 17607.

 0.68 17231.

 5.23 112163.

 5.23 112418.

 5.23 112412.

 4.96 106133.

 4.97 106247.

 4.96 106267.

 4.68 99913.

 4.68 99879.

 4.68 100030.

 4.40 94157.

 4.39 94182.

 4.41 94292.

 4.13 87926.

 4.13 88032.

 4.13 87811.

 3.83 81978.

 3.82 81943.

 3.82 82076.

 3.54 76454.

 3.54 76753.

 3.55 76977.

 3.30 71199.

 3.30 71279.

 3.30 71248.

 3.05 65899.

 3.04 65798.

 3.04 65711.

 2.81 60334.

 2.81 60518.

 2.81 60492.

 2.56 54983.

 2.56 55042.

 2.56 55018.

 2.32 50257.

 2.31 50222.

 2.31 49979.

 2.08 45181.

 2.08 44950.

 2.08 45050.

 1.85 40408.

 1.85 39984.

 1.84 40061.

 1.58 35069.

 1.58 35030.

 1.58 34865.

 1.35 30558.

 1.34 30444.

 1.35 30356.

 1.13 25888.

 1.11 25820.

 1.11 25630.

 0.90 21395.

 0.89 21156.

 0.89 21076.

 0.66 16974.

 0.66 17090.

 0.66 16980.

 0.49 13177.

 0.48 13099.

 5.16 112641.

 5.16 112652.

 5.16 112728.

 4.85 105831.

 4.85 106161.

 4.85 106190.

 4.59 100438.

 4.59 100556.

 4.62 100541.

 4.34 94220.

 4.35 94095.

 4.36 94479.

 4.09 88517.

 4.09 88688.

 4.09 88737.

 3.80 82797.

 3.81 83177.

 3.81 83343.

 3.52 77297.

 3.52 77898.

 3.54 77606.

 3.28 72256.

 3.29 72034.

 3.30 72097.

 3.03 66851.

 3.03 66749.

 3.03 66936.

 2.79 61452.

 2.78 61198.

 2.78 61118.

 2.53 56104.

 2.52 56127.

 2.52 56236.

 2.27 50995.

 2.27 50728.

 2.27 50778.

 2.07 45733.

 2.06 45497.

 2.06 45437.

 1.81 40641.

 1.80 40706.

 1.80 40575.

 1.56 35634.

 1.57 35484.

 1.56 35404.

 1.35 31141.

 1.35 30862.

 1.35 30821.

 1.12 26359.

 1.11 25977.

 1.10 26067.

 0.90 22023.

 0.88 21811.

 0.88 21816.

 0.68 17885.

 0.66 17578.

 0.66 17542.

 0.47 13354.

 0.47 13231.

 5.07 112580.

 5.07 112663.

 5.07 112818.

 4.81 106509.

 4.80 106616.

 4.80 106912.

 4.53 100410.

 4.51 100531.

 4.51 100610.

 4.24 94491.

 4.24 94649.

 4.24 94651.

 3.99 88749.

 4.00 88620.

 3.99 88877.

 3.72 83071.

 3.73 82850.

 3.74 83056.

 3.48 77524.

 3.49 77806.

 3.51 77711.

 3.25 71793.
20

 3.26 71990.

 3.26 72043.

 3.02 66587.

 3.01 66696.

 3.01 66741.

 2.75 61184.

 2.75 61248.

 2.75 61244.

 2.51 55943.

 2.49 56089.

 2.50 56029.

 2.26 50753.

 2.26 50533.

 2.27 50353.

 2.03 45796.

 2.03 45740.

 2.04 45827.

 1.81 40463.

 1.79 40360.

 1.80 40159.

 1.56 35388.

 1.54 35298.

 1.54 35332.

 1.33 30823.

 1.33 30792.

 1.33 30762.

 1.12 26308.

 1.09 26160.

 1.09 26034.

 0.89 22047.

 0.87 21919.

 0.88 21860.

 0.69 17565.

 0.66 17128.

 0.66 16982.

 0.47 13295.

 0.46 13295.

 5.05 112931.

 5.06 112570.

 5.07 112632.

 4.81 106690.

 4.82 106874.

 4.81 106735.

 4.53 100591.

 4.54 100662.

 4.54 100788.

 4.27 94735.

 4.25 94753.

 4.26 94881.

 3.99 88864.

 3.99 88978.

 3.99 88963.

 3.72 82454.

 3.74 82692.

 3.73 82687.

 3.47 77205.

 3.47 77248.

 3.46 77210.

 3.22 71685.

 3.21 71503.

 3.23 71599.

 2.97 66544.

 2.96 66379.

 2.97 66192.

 2.71 60949.

 2.72 61060.

 2.72 61017.

 2.47 55871.

 2.47 55809.

 2.47 55871.

 2.24 50656.

 2.23 50486.

 2.22 50460.

 1.99 45418.

 1.99 45635.

 2.00 45752.

 1.78 40505.

 1.78 40406.

 1.77 40445.

 1.53 35249.

 1.53 35024.

 1.53 35056.

 1.31 30671.

 1.30 30453.

 1.30 30394.

 1.09 26181.

 1.08 25889.

 1.08 25873.

 0.88 21763.

 0.87 21681.

 0.88 21656.

 0.68 17447.

 0.68 17246.

 0.68 17177.

 0.49 13285.

 0.47 13217.

 5.08 112508.

 5.09 112788.

 5.10 112540.

 4.82 106262.

 4.81 106456.

 4.82 106619.

 4.55 100402.

 4.55 100376.

 4.56 100228.

 4.27 94606.

 4.28 94567.

 4.31 94840.

 4.03 88810.

 4.03 88850.

 4.02 89012.

 3.74 82740.

 3.74 82748.

 3.74 82893.

 3.48 77361.

 3.47 77428.

 3.48 77308.

 3.21 71833.

 3.20 71971.

 3.21 72048.

 2.96 66765.

 2.97 66810.

 2.96 66680.

 2.71 61818.

 2.72 61526.

 2.72 61488.

 2.45 55716.

 2.45 55958.

 2.45 55888.

 2.19 50663.

 2.19 50565.

 2.19 50444.

 1.99 45898.

 1.98 45619.

 1.98 45664.

 1.76 40647.

 1.76 40519.

 1.76 40406.

 1.52 35419.

 1.52 35132.

 1.52 35085.

 1.30 30841.

 1.29 30801.

 1.31 30646.

 1.07 26323.

 1.06 26007.

 1.06 25980.

 0.86 21936.

 0.86 21810.

 0.85 21825.

R134a/1Al0 (99/1)

File: RFAl5.dat ∆Ts

(K)

q" 

(W/m

2

)

 5.90 110502.

 5.89 110450.

 5.90 110621.

 5.62 105016.

 5.62 105149.

 5.63 105259.

 5.34 99359.

 5.35 99453.

 5.35 99417.

 5.05 93478.

 5.06 93498.

 5.06 93605.

 4.76 87958.

 4.76 88128.

 4.77 88093.

 4.45 82156.

 4.46 82219.

 4.45 82108.

 4.12 76405.

 4.12 76591.

 4.13 76702.

 3.82 71015.

 3.81 70909.

 3.81 71028.

 3.51 65763.

 3.51 65662.

 3.52 65855.

 3.22 60432.

 3.22 60280.

 3.23 60247.

 2.94 55154.

 2.95 55222.

 2.95 55118.

 2.68 50321.

 2.68 50368.
21

 2.68 50352.

 2.41 45139.

 2.40 45067.

 2.40 44910.

 2.14 40315.

 2.14 40174.

 2.14 40093.

 1.88 35219.

 1.87 35234.

 1.88 35151.

 1.62 30734.

 1.63 30721.

 1.63 30632.

 1.40 26418.

 1.37 25880.

 1.38 26012.

 1.13 22045.

 1.11 21821.

 1.11 21798.

 0.90 17851.

 0.88 17562.

 0.88 17544.

 0.66 13711.

 0.63 13237.

 0.62 13099.

 0.46 10625.

 0.39 9768.

 5.68 109447.

 5.69 110492.

 5.71 110591.

 5.42 104581.

 5.44 104848.

 5.47 104204.

 5.22 99194.

 5.23 99094.

 5.24 99380.

 4.94 93738.

 4.95 93783.

 4.96 93760.

 4.64 87724.

 4.64 87858.

 4.64 87824.

 4.32 81953.

 4.32 82101.

 4.32 82086.

 4.01 76490.

 4.01 76647.

 4.02 76611.

 3.72 70794.

 3.71 70652.

 3.72 70675.

 3.43 65531.

 3.43 65661.

 3.44 65723.

 3.17 60162.

 3.16 60095.

 3.16 60035.

 2.88 55019.

 2.88 55164.

 2.88 55080.

 2.64 50285.

 2.63 50174.

 2.63 50059.

 2.37 45198.

 2.37 45208.

 2.37 45180.

 2.11 40216.

 2.10 39977.

 2.10 40028.

 1.85 35513.

 1.84 35343.

 1.84 35451.

 1.59 30808.

 1.59 30709.

 1.60 30517.

 1.36 26572.

 1.35 26347.

 1.34 26134.

 1.09 21967.

 1.08 21741.

 1.07 21716.

 0.87 17789.

 0.85 17369.

 0.85 17256.

 0.61 13593.

 0.59 13435.

 5.58 110468.

 5.59 110516.

 5.59 110492.

 5.34 104572.

 5.37 104793.

 5.43 104249.

 5.14 99488.

 5.16 99527.

 5.15 99662.

 4.86 93618.

 4.86 93631.

 4.86 93758.

 4.56 87944.

 4.56 88014.

 4.57 88065.

 4.25 81817.

 4.24 81802.

 4.25 81964.

 3.94 76368.

 3.93 76367.

 3.95 76501.

 3.66 71022.

 3.65 70995.

 3.65 71086.

 3.38 65457.

 3.38 65611.

 3.37 65498.

 3.10 60278.

 3.10 60328.

 3.10 60360.

 2.84 55012.

 2.84 54979.

 2.82 54917.

 2.58 50058.

 2.57 50019.

 2.57 50060.

 2.32 45302.

 2.31 45371.

 2.32 45307.

 2.08 40440.

 2.08 40205.

 2.09 40095.

 1.81 35277.

 1.80 35232.

 1.78 35245.

 1.54 30579.

 1.54 30374.

 1.55 30298.

 1.32 26294.

 1.31 26138.

 1.31 26191.

 1.09 21579.

 1.05 21370.

 1.05 21316.

 0.84 17527.

 0.81 17254.

 0.81 17119.

 0.59 13812.

 0.57 13391.

 5.57 110368.

 5.58 110631.

 5.59 111052.

 5.32 104194.

 5.32 104437.

 5.35 104637.

 5.06 98766.

 5.07 98865.

 5.07 99053.

 4.79 93240.

 4.79 93235.

 4.80 93535.

 4.51 87631.

 4.51 87745.

 4.52 87864.

 4.20 81906.

 4.21 82125.

 4.20 82041.

 3.92 76088.

 3.93 76360.

 3.93 76228.

 3.63 70904.

 3.64 70895.

 3.64 70659.

 3.35 65280.

 3.35 65330.

 3.36 65314.

 3.09 60135.

 3.09 60283.

 3.10 60362.

 2.86 55310.

 2.85 55190.

 2.86 55236.

 2.60 50287.

 2.59 50269.

 2.60 50225.

 2.34 45240.

 2.34 45188.

 2.34 45239.

 2.09 40465.

 2.09 40267.

 2.07 40201.

 1.83 35257.

 1.81 34941.

 1.81 34977.

 1.57 30547.

 1.57 30374.

 1.57 30443.

 1.34 26409.

 1.34 26194.
22

 1.33 26187.

 1.09 21848.

 1.07 21644.

 1.08 21581.

 0.86 17897.

 0.84 17490.

 0.83 17344.

 0.61 13607.

 0.60 13388.

 5.55 110539.

 5.57 110647.

 5.60 109672.

 5.34 105082.

 5.35 105206.

 5.37 105276.

 5.08 99514.

 5.09 99455.

 5.10 99510.

 4.81 93545.

 4.80 93596.

 4.81 93725.

 4.52 88080.

 4.51 88196.

 4.53 88142.

 4.21 82053.

 4.21 82153.

 4.21 82082.

 3.92 76488.

 3.91 76587.

 3.92 76608.

 3.63 70995.

 3.62 71050.

 3.62 71096.

 3.34 65475.

 3.34 65619.

 3.35 65637.

 3.07 60223.

 3.07 60235.

 3.07 60277.

 2.81 55065.

 2.81 55002.

 2.81 54849.

 2.56 50416.

 2.56 50401.

 2.56 50399.

 2.31 45259.

 2.31 45212.

 2.30 45243.

 2.06 40234.

 2.05 40200.

 2.05 40178.

 1.78 35178.

 1.77 35146.

 1.77 35084.

 1.51 30406.

 1.52 30530.

 1.51 30236.

 1.30 26208.

 1.30 26089.

 1.31 26223.

 1.07 21781.

 1.06 21709.

 1.07 21679.

 0.86 18022.

 0.83 17574.

 0.82 17505.

 0.60 13538.

 0.58 13243.

 5.51 110614.

 5.52 110776.

 5.54 110830.

 5.27 104484.

 5.30 104683.

 5.30 104707.

 5.04 99420.

 5.04 99276.

 5.05 99220.

 4.77 93696.

 4.76 93747.

 4.78 93880.

 4.48 87871.

 4.49 87946.

 4.50 88061.

 4.18 82043.

 4.18 81999.

 4.18 82137.

 3.88 76362.

 3.89 76451.

 3.90 76659.

 3.62 71141.

 3.63 71227.

 3.63 71332.

 3.36 65680.

 3.36 65691.

 3.36 65758.

 3.07 60478.

 3.07 60436.

 3.09 60599.

 2.82 55386.

 2.83 55465.

 2.83 55470.

 2.58 50428.

 2.56 50461.

 2.56 50467.

 2.31 45475.

 2.31 45313.

 2.31 45315.

 2.06 40233.

 2.04 40053.

 2.04 39979.

 1.78 35397.

 1.76 35151.

 1.76 35242.

 1.53 30726.

 1.52 30610.

 1.53 30728.

 1.31 26604.

 1.29 26183.

 1.30 26213.

 1.07 22111.

 1.05 21780.

 1.04 21742.

 0.85 18105.

 0.81 17674.

 0.81 17576.

 0.60 13345.

 0.59 13113.

 0.59 12839.

 0.38 9525.

 0.36 9461.

 5.55 110750.

 5.56 110846.

 5.57 110887.

 5.31 105007.

 5.31 105261.

 5.32 105316.

 5.04 99384.

 5.04 99412.

 5.05 99403.

 4.77 93858.

 4.77 93901.

 4.77 93840.

 4.48 87913.

 4.47 88021.

 4.49 88036.

 4.17 81843.

 4.17 81843.

 4.16 81811.

 3.87 76302.

 3.87 76340.

 3.87 76506.

 3.59 70714.

 3.59 70805.

 3.58 70755.

 3.30 65473.

 3.30 65566.

 3.31 65676.

 3.04 60363.

 3.04 60354.

 3.04 60332.

 2.78 55164.

 2.78 55030.

 2.79 54944.

 2.53 50097.

 2.52 49984.

 2.53 50135.

 2.29 45379.

 2.28 45308.

 2.28 45205.

 2.03 40447.

 2.04 40383.

 2.04 40356.

 1.79 35241.

 1.78 35058.

 1.77 34917.

 1.51 30508.

 1.50 30309.

 1.49 30263.

 1.28 26088.

 1.28 25981.

 1.28 25956.

 1.04 21952.

 1.03 21664.

 1.02 21510.

 0.81 17554.

 0.79 17321.

 0.79 17247.

 0.62 13705.

 0.59 13271.

 0.59 13189.
23

R134a/2Al0 (99/1)

File: TBCAL81.dat ∆Ts

(K)

q" 

(W/m

2

)

 5.94 110548.

 5.93 110718.

 5.93 110844.

 5.60 104410.

 5.60 104760.

 5.62 104951.

 5.30 99080.

 5.32 99209.

 5.32 99209.

 5.01 93418.

 5.03 93509.

 5.02 93497.

 4.72 87776.

 4.72 87901.

 4.73 87900.

 4.43 82193.

 4.42 82166.

 4.42 82341.

 4.14 76724.

 4.14 76679.

 4.13 76738.

 3.84 71071.

 3.84 71064.

 3.83 71070.

 3.54 65569.

 3.54 65565.

 3.54 65602.

 3.25 60277.

 3.25 60322.

 3.25 60368.

 2.96 55054.

 2.97 55114.

 2.96 55064.

 2.70 50094.

 2.69 49998.

 2.68 49983.

 2.41 44919.

 2.40 44826.

 2.40 44911.

 2.13 39794.

 2.11 39703.

 2.11 39711.

 1.85 34963.

 1.83 34886.

 1.84 34977.

 1.60 30602.

 1.59 30521.

 1.58 30454.

 1.35 26164.

 1.35 26035.

 1.35 25950.

 1.13 21869.

 1.10 21500.

 1.10 21346.

 0.88 17767.

 0.84 17263.

 0.84 17175.

 0.63 13924.

 0.60 13547.

 0.60 13528.

 0.44 9569.

 0.43 9200.

 5.80 110207.

 5.79 110965.

 5.80 111047.

 5.50 105071.

 5.51 105202.

 5.51 105230.

 5.23 99382.

 5.23 99166.

 5.23 99155.

 4.93 93274.

 4.92 93415.

 4.92 93573.

 4.64 87996.

 4.65 88227.

 4.66 88028.

 4.34 82115.

 4.34 82014.

 4.34 82066.

 4.05 76695.

 4.05 76743.

 4.03 76714.

 3.77 71157.

 3.77 71135.

 3.77 71031.

 3.48 65720.

 3.48 65525.

 3.48 65605.

 3.19 60321.

 3.17 60397.

 3.18 60364.

 2.89 55080.

 2.89 55063.

 2.90 54961.

 2.62 50089.

 2.62 50127.

 2.61 50090.

 2.34 45142.

 2.32 44950.

 2.31 44899.

 2.06 39892.

 2.05 39691.

 2.06 39639.

 1.78 34775.

 1.78 34827.

 1.78 34790.

 1.55 30531.

 1.55 30220.

 1.55 30297.

 1.33 26201.

 1.32 25985.

 1.32 25927.

 1.08 21745.

 1.06 21601.

 1.05 21519.

 0.84 17873.

 0.81 17463.

 0.82 17397.

 0.62 13714.

 0.60 13340.

 0.60 13333.

 0.41 9869.

 0.39 9551.

 5.66 111778.

 5.67 111544.

 5.67 111605.

 5.38 105285.

 5.39 105309.

 5.40 105390.

 5.11 99524.

 5.12 99595.

 5.12 99671.

 4.83 93761.

 4.84 93742.

 4.84 93733.

 4.58 87949.

 4.58 87927.

 4.57 87953.

 4.28 82244.

 4.29 82275.

 4.29 82338.

 4.00 76635.

 4.00 76758.

 4.00 76799.

 3.73 71248.

 3.71 71167.

 3.72 71220.

 3.42 65748.

 3.42 65631.

 3.41 65518.

 3.12 60162.

 3.12 60341.

 3.12 60337.

 2.86 55247.

 2.85 55103.

 2.85 55181.

 2.60 50136.

 2.59 50137.

 2.58 50117.

 2.33 44634.

 2.31 44446.

 2.31 44405.

 2.05 40190.

 2.04 40013.

 2.04 39915.

 1.78 34854.

 1.79 35071.

 1.79 35021.

 1.55 30618.

 1.54 30378.

 1.55 30421.

 1.30 26001.

 1.31 26102.

 1.31 26045.

 1.07 21833.

 1.06 21420.

 1.05 21275.

 0.84 17506.

 0.82 17259.

 0.82 17190.

 0.61 13825.

 0.58 13549.

 0.59 13481.

 0.43 9827.

 0.40 9252.

 5.61 111718.

 5.63 111864.

 5.62 111305.
24

 5.35 105244.

 5.35 105269.

 5.36 105429.

 5.15 99485.

 5.17 98702.

 5.16 99799.

 4.88 93606.

 4.89 93742.

 4.88 94032.

 4.59 88178.

 4.60 88179.

 4.61 88329.

 4.30 82218.

 4.30 82444.

 4.31 82529.

 4.02 76698.

 4.01 76758.

 4.01 76469.

 3.71 71351.

 3.73 71402.

 3.73 71084.

 3.42 65561.

 3.42 65691.

 3.42 65916.

 3.13 60236.

 3.14 60453.

 3.15 60382.

 2.85 55235.

 2.86 54910.

 2.86 55288.

 2.59 50252.

 2.58 49938.

 2.58 49798.

 2.30 44749.

 2.29 44548.

 2.29 44554.

 2.01 39869.

 2.01 39902.

 2.02 40167.

 1.78 35125.

 1.78 35311.

 5.65 111632.

 5.66 111694.

 5.67 111814.

 5.40 104619.

 5.38 105370.

 5.38 105669.

 5.10 99783.

 5.09 99816.

 5.10 99884.

 4.83 94262.

 4.84 94231.

 4.83 94165.

 4.56 88398.

 4.55 88508.

 4.57 88520.

 4.27 82413.

 4.27 82438.

 4.28 82424.

 3.98 76798.

 3.98 76870.

 3.98 76820.

 3.70 71256.

 3.69 71218.

 3.68 71216.

 3.41 65889.

 3.41 65984.

 3.41 66075.

 3.14 60579.

 3.14 60599.

 3.13 60607.

 2.86 55220.

 2.86 55163.

 2.87 54989.

 2.60 50261.

 2.59 50297.

 2.60 50384.

 2.35 44867.

 2.34 44802.

 2.33 44588.

 2.04 40134.

 2.04 40112.

 2.05 40036.

 1.80 35192.

 1.80 35188.

 1.80 34964.

 1.56 30435.

 1.56 30259.

 1.55 30212.

 1.32 26042.

 1.33 26018.

 1.32 25777.

 1.11 21970.

 1.07 21648.

 1.07 21674.

 0.87 18010.

 0.84 17517.

 0.85 17581.

 0.63 13527.

 0.60 13249.

 0.61 13239.

 0.41 9712.

 0.40 9593.

 5.86 112087.

 5.88 112324.

 5.90 112146.

 5.62 105729.

 5.61 105654.

 5.62 105618.

 5.33 99686.

 5.34 99836.

 5.34 99943.

 5.07 94141.

 5.07 94233.

 5.08 94365.

 4.80 88252.

 4.80 88245.

 4.82 88075.

 4.53 82650.

 4.52 82921.

 4.52 82909.

 4.24 77223.

 4.23 77255.

 4.23 77227.

 3.93 71678.

 3.92 71739.

 3.93 71683.

 3.63 66136.

 3.63 66182.

 3.62 66124.

 3.33 60830.

 3.33 60828.

 3.33 60789.

 3.03 55544.

 3.03 55431.

 3.01 55442.

 2.73 50080.

 2.73 50204.

 2.73 50105.

 2.43 45080.

 2.42 45141.

 2.43 45174.

 2.15 39765.

 2.15 39511.

 2.14 39413.

 1.85 35233.

 1.86 35328.

 1.86 35232.

 1.61 30536.

 1.61 30255.

 1.61 30208.

 1.36 25758.

 1.36 25655.

 1.36 25522.

 1.10 21298.

 1.08 21130.

 1.08 21090.

 0.84 17302.

 0.83 17172.

 5.72 111639.

 5.75 111890.

 5.76 111751.

 5.46 105425.

 5.46 105565.

 5.48 105584.

 5.20 99470.

 5.21 99693.

 5.22 99673.

 4.93 93564.

 4.94 93786.

 4.94 93918.

 4.67 88434.

 4.67 88535.

 4.66 88505.

 4.39 82547.

 4.37 82478.

 4.38 82637.

 4.09 76886.

 4.09 76967.

 4.10 76958.

 3.80 71368.

 3.80 71525.

 3.80 71514.

 3.53 66065.

 3.52 66027.

 3.53 66081.

 3.24 60553.

 3.23 60507.

 3.23 60452.

 2.95 55432.

 2.94 55417.

 2.95 55494.

 2.68 50432.

 2.67 50387.

 2.67 50365.
25

 2.40 44907.

 2.39 44875.

 2.40 44792.

 2.11 40084.

 2.09 39956.

 2.10 39955.

 1.84 35375.

 1.83 35391.

 1.84 35274.

 1.60 30595.

 1.60 30424.

 1.59 30253.

 1.32 26094.

 1.33 26182.

 1.34 26306.

 1.11 22147.

 1.11 21990.

 1.10 21798.

 0.87 17967.

 0.86 17544.

 0.85 17655.

 0.64 13977.

 0.61 13676.

 0.61 13617.

 0.44 9699.

 0.43 9377.

 5.65 111056.

 5.65 111006.

 5.68 111059.

 5.41 104849.

 5.43 105058.

 5.43 105020.

 5.15 99393.

 5.17 99494.

 5.17 99487.

 4.89 93728.

 4.89 93769.

 4.90 93803.

 4.61 87987.

 4.62 87938.

 4.63 87328.

 4.33 82389.

 4.33 82269.

 4.34 82311.

 4.04 76458.

 4.04 76563.

 4.05 76541.

 3.75 71262.

 3.76 71424.

 3.76 71482.

 3.48 65921.

 3.48 65781.

 3.49 65603.

 3.19 60358.

 3.18 60399.

 3.18 60392.

 2.91 55291.

 2.90 55418.

 2.91 55514.

 2.65 50180.

 2.66 50250.

 2.64 50221.

 2.38 45068.

 2.37 44834.

 2.38 44983.

 2.09 40241.

 2.08 40210.

 2.08 40143.

 1.83 35336.

 1.83 35441.

 1.83 35440.

 1.59 30847.

 1.58 30701.

 1.58 30604.

 1.35 26342.

 1.33 26006.

 1.33 25909.

 1.09 21942.

 1.06 21643.

 1.06 21551.

 0.85 17807.

 0.83 17588.

 0.82 17408.

 0.62 13700.

 0.60 13328.

 0.59 13385.

 0.41 9873.

 0.39 9562.

 5.61 111429.

 5.64 111698.

 5.66 111928.

 5.39 105416.

 5.41 105438.

 5.43 105466.

 5.14 99385.

 5.14 99373.

 5.15 99323.

 4.88 93763.

 4.88 93855.

 4.88 93892.

 4.61 87384.

 4.59 88012.

 4.61 88108.

 4.31 82357.

 4.33 81433.

 4.32 82468.

 4.04 76769.

 4.03 76799.

 4.02 76715.

 3.74 71143.

 3.73 71200.

 3.74 71105.

 3.44 65755.

 3.43 65525.

 3.45 65753.

 3.15 60394.

 3.14 60333.

 3.15 60255.

 2.85 55266.

 2.86 55404.

 2.87 55316.

 2.62 49974.

 2.61 49880.

 2.62 49905.

 2.33 44998.

 2.33 44904.

 2.33 44951.

 2.07 39865.

 2.05 39951.

 2.05 39896.

 1.80 35225.

 1.79 35013.

 1.79 35217.

 1.54 30520.

 1.55 30411.

 1.53 30347.

 1.31 26039.

 1.29 25717.

 1.29 25557.

 1.06 21940.

 1.04 21659.

 1.04 21575.

 0.84 17916.

 0.82 17652.

 0.82 17544.

 0.62 13832.

 0.59 13371.

 0.58 13264.

 0.39 9629.

 0.38 9428.

 5.77 111716.

 5.77 111733.

 5.78 111541.

 5.51 104306.

 5.50 105270.

 5.49 105319.

 5.23 98350.

 5.22 99326.

 5.22 99244.

 4.93 93777.

 4.93 93633.

 4.93 93745.

 4.65 88029.

 4.66 88130.

 4.65 88090.

 4.36 82244.

 4.36 82138.

 4.37 82324.

 4.07 76606.

 4.06 76740.

 4.07 76723.

 3.78 71410.

 3.78 71571.

 3.79 71693.

 3.50 66087.

 3.50 66023.

 3.50 66079.

 3.22 60671.

 3.20 60632.

 3.21 60639.

 2.92 55507.

 2.91 55446.

 2.92 55432.

 2.63 50172.

 2.64 50218.

 2.63 50176.

 2.35 45192.

 2.35 45160.

 2.33 45073.

 2.07 39922.

 2.05 39761.

 2.05 39620.

 1.79 35263.

 1.77 35200.

 1.77 35182.
26

 1.55 30402.

 1.54 30406.

 1.54 30370.

 1.30 26331.

 1.27 26187.

 1.29 26181.

 1.06 21339.

 1.06 21137.

 5.79 110694.

 5.79 110534.

 5.81 110246.

 5.53 104385.

 5.58 99872.

 5.52 104658.

 5.25 98862.

 5.26 98792.

 5.25 98835.

 4.96 93179.

 4.97 93121.

 4.98 93146.

 4.69 87640.

 4.69 87631.

 4.69 87521.

 4.41 81660.

 4.39 81622.

 4.39 81738.

 4.11 76287.

 4.11 76207.

 4.11 76271.

 3.84 70777.

 3.83 70809.

 3.85 70930.

 3.56 65412.

 3.54 65124.

 3.54 65189.

 3.18 57849.

 3.09 57058.

 3.20 58774.

 2.96 54423.

 2.96 54460.

 2.97 54527.

 2.69 49677.

 2.67 49409.

 2.67 49435.

 2.42 44261.

 2.39 44322.

 2.38 44104.

 2.14 39594.

 2.11 39213.

 2.10 39270.

 1.86 34614.

 1.84 34603.

 1.85 34588.

 1.61 30093.

 1.60 29908.

 1.58 29684.

 1.38 25505.

 1.38 25288.

 1.37 25168.

 1.04 20027.

 1.11 21047.

 5.68 111593.

 5.67 111869.

 5.70 110925.

 5.40 104482.

 5.39 104742.

 5.42 105080.

 5.13 98717.

 5.13 98693.

 5.13 99236.

 4.84 93522.

 4.85 93791.

 4.86 93861.

 4.61 88071.

 4.61 87787.

 4.61 88240.

 4.20 79963.

 4.28 81282.

 4.34 80494.

 3.87 73102.

 3.97 75448.

 4.03 76355.

 3.78 71007.

 3.77 71361.

 3.78 71253.

 3.50 65532.

 3.49 65453.

 3.49 65498.

 3.21 59982.

 3.21 59749.

 3.20 59996.

 2.91 54970.

 2.91 55106.

 2.92 54991.

 2.65 49841.

 2.76 49337.

 2.73 49594.

 2.42 44579.

 2.41 44445.

 2.41 44392.

 2.14 39602.

 2.12 39386.

 2.11 39195.

 1.87 34488.

 1.85 34468.

 1.92 33834.

 1.61 29968.

 1.61 30057.

 1.62 30069.

 1.40 25411.

 5.68 110802.

 5.67 111665.

 5.70 111728.

 5.41 104866.

 5.41 104974.

 5.40 104951.

 5.12 99084.

 5.13 99186.

 5.12 99208.

 4.85 92946.

 4.85 93658.

 4.74 91467.

 4.56 87936.

 4.58 88044.

 4.58 88125.

 4.29 82293.

 4.29 82291.

 4.29 82282.

 4.02 76356.

 4.02 76362.

 4.02 76303.

 3.74 71061.

 3.73 71120.

 3.74 71218.

 3.46 65653.

 3.45 65674.

 3.45 65670.

 3.16 60219.

 3.16 60230.

 3.16 60242.

 2.88 55041.

 2.88 54978.

 2.87 54925.

 2.61 49865.

 2.60 49650.

 2.59 49645.

 2.33 44744.

 2.32 44583.

 2.32 44615.

 2.07 39843.

 2.05 39688.

 2.05 39743.

 1.82 34729.

 1.80 34592.

 1.81 34582.

 1.57 30014.

 1.55 29771.

 1.56 29748.

 1.32 25747.

 1.31 25636.

 1.30 25609.

 1.10 21902.

 1.07 21404.

 1.06 21362.

 0.87 17704.

 0.86 17433.

 0.85 17226.

 0.64 13382.

 0.62 13228.

 0.62 13084.

R134a/5Al0 (99/1)

File: TBCAL17.dat ∆Ts

(K)

q" 

(W/m

2

)

 6.50 106979.

 6.49 106675.

 6.49 106483.

 6.24 100731.

 6.24 100855.

 6.26 100942.

 6.00 95112.

 5.98 95170.

 6.00 95176.

 5.72 89359.

 5.71 89315.

 5.72 89363.

 5.43 83463.

 5.42 83453.

 5.43 83449.
27

 5.10 77446.

 5.09 77369.

 5.10 77415.

 4.82 72015.

 4.82 72069.

 4.82 72159.

 4.53 66554.

 4.53 66515.

 4.53 66466.

 4.22 61317.

 4.22 61341.

 4.22 61368.

 3.88 55926.

 3.88 55951.

 3.88 55921.

 3.58 51123.

 3.57 51217.

 3.59 51207.

 3.27 46506.

 3.27 46522.

 3.27 46486.

 2.92 41726.

 2.93 41736.

 2.93 41664.

 2.60 37205.

 2.60 37212.

 2.58 37133.

 2.29 32849.

 2.27 32701.

 2.27 32665.

 1.98 28439.

 1.94 28236.

 1.95 28187.

 1.64 23905.

 1.63 23919.

 1.63 23921.

 1.34 20106.

 1.33 19974.

 1.32 19985.

 1.10 16755.

 1.05 16338.

 1.04 16252.

 0.78 12565.

 0.76 12430.

 6.86 105619.

 6.87 105871.

 6.88 106080.

 6.53 99465.

 6.53 99491.

 6.52 99435.

 6.18 93484.

 6.18 93631.

 6.18 93586.

 5.83 88053.

 5.83 88041.

 5.84 88078.

 5.50 82593.

 5.50 82627.

 5.50 82625.

 5.17 77245.

 5.17 77320.

 5.17 77429.

 4.84 72150.

 4.85 72209.

 4.86 72277.

 4.53 67046.

 4.53 67179.

 4.55 67276.

 4.21 61885.

 4.21 61786.

 4.21 61755.

 3.87 56466.

 3.88 56538.

 3.87 56521.

 3.54 51605.

 3.54 51628.

 3.54 51594.

 3.21 46870.

 3.22 46929.

 3.22 47014.

 2.89 42166.

 2.88 42048.

 2.88 41953.

 2.56 37278.

 2.54 37192.

 2.55 37287.

 2.26 33104.

 2.25 33049.

 2.25 33025.

 1.96 28871.

 1.95 28776.

 1.95 28707.

 1.67 24734.

 1.65 24561.

 1.66 24513.

 1.38 20650.

 1.35 20364.

 1.35 20232.

 1.09 16896.

 1.06 16531.

 6.69 106276.

 6.70 106420.

 6.70 106092.

 6.35 99607.

 6.35 99535.

 6.36 99503.

 6.03 94023.

 6.03 94165.

 6.03 94238.

 5.71 88727.

 5.71 88815.

 5.72 88901.

 5.38 83206.

 5.38 83212.

 5.38 83227.

 5.04 77463.

 5.04 77428.

 5.04 77450.

 4.72 71998.

 4.72 72113.

 4.73 72150.

 4.39 66889.

 4.39 66930.

 4.40 66951.

 4.08 61730.

 4.06 61630.

 4.07 61647.

 3.73 56459.

 3.74 56525.

 3.73 56437.

 3.42 51587.

 3.41 51513.

 3.41 51589.

 3.10 46739.

 3.10 46765.

 3.10 46749.

 2.77 41858.

 2.77 41775.

 2.76 41687.

 2.46 37351.

 2.44 37342.

 2.45 37316.

 2.18 32943.

 2.17 32898.

 2.16 32860.

 1.90 28756.

 1.88 28630.

 1.87 28581.

 1.61 24582.

 1.59 24424.

 1.59 24461.

 1.35 20806.

 1.31 20438.

 1.31 20340.

 1.07 16816.

 1.05 16552.

 6.59 106389.

 6.60 106610.

 6.61 106698.

 6.28 100351.

 6.27 100409.

 6.28 100471.

 5.96 94454.

 5.95 94469.

 5.96 94496.

 5.63 88763.

 5.64 88899.

 5.63 88951.

 5.32 83335.

 5.32 83415.

 5.31 83360.

 4.99 77646.

 4.99 77684.

 4.99 77697.

 4.68 72295.

 4.69 72421.

 4.69 72414.

 4.38 66836.

 4.37 66788.

 4.36 66726.

 4.04 61451.

 4.05 61583.

 4.04 61638.

 3.74 56633.

 3.74 56711.

 3.74 56797.

 3.44 51634.

 3.43 51546.

 3.41 51403.

 3.09 46749.

 3.10 46952.

 3.11 47170.

 2.80 41995.

 2.77 41817.

 2.78 41747.
28

 2.48 37332.

 2.45 37237.

 2.47 37184.

 2.18 33023.

 2.18 32967.

 2.18 32975.

 1.92 28727.

 1.90 28629.

 1.90 28570.

 1.62 24562.

 1.61 24392.

 1.61 24356.

 1.35 20751.

 1.33 20430.

 1.32 20409.

 1.08 16852.

 1.06 16459.

 6.52 106422.

 6.52 106531.

 6.51 106396.

 6.20 100198.

 6.19 100134.

 6.19 100115.

 5.86 94140.

 5.86 94301.

 5.87 94329.

 5.55 88581.

 5.55 88619.

 5.55 88604.

 5.24 82998.

 5.23 82943.

 5.23 82966.

 4.91 77375.

 4.91 77437.

 4.91 77506.

 4.60 72149.

 4.61 72200.

 4.61 72206.

 4.30 66929.

 4.30 67022.

 4.31 67032.

 3.98 61563.

 3.98 61615.

 3.98 61612.

 3.66 56269.

 3.66 56242.

 3.65 56177.

 3.34 51446.

 3.34 51546.

 3.36 51620.

 3.05 46791.

 3.04 46743.

 3.05 46771.

 2.73 41776.

 2.73 41821.

 2.73 41760.

 2.44 37456.

 2.43 37463.

 2.43 37481.

 2.17 33235.

 2.16 33167.

 2.16 33102.

 1.89 29002.

 1.87 28829.

 1.87 28752.

 1.59 24646.

 1.58 24652.

 1.58 24613.

 1.31 20557.

 1.30 20491.

 1.30 20467.

 1.05 16913.

 1.03 16693.

 1.03 16668.
29

Table 3 Number of test days and data points

Fluid (% mass fraction) Number of days Number of data points

Pure R134a 

1.6 K ≤ ∆Ts ≤ 5.0 K

3 118

R134a/RL68H (99.5/0.5) 

1. 7 K ≤ ∆Ts ≤ 5.6 K

5 212

R134a/RL68H (99/1) 

0.6 K ≤ ∆Ts ≤ 6.0 K

8 359

R134a/1AlO (99.5/0.5) 

0.4 K ≤ ∆Ts ≤ 5.2 K

7 402

R134a/1AlO (99/1) 

0.4 K ≤ ∆Ts ≤ 5.8 K

7 420

R134a/2AlO (99/1) 

0.4 K ≤ ∆Ts ≤ 5.8 K

13 749

R134a/5AlO (99/1) 

0.8 K ≤ ∆Ts ≤ 6.7 K

5 284
30

Table 4 Estimated parameters for cubic boiling curve fits for Turbo-BII-HP copper 

surface

∆Ts = A0 + A1 q” + A2 q”2 + A3 q”3

∆Ts in kelvin and q” in W/m2

Fluid Ao A1 A2 A3

Pure R134a 

1.6 K ≤ ∆Ts ≤ 5.0 K 0.107591 4.31453x10-5 1.55837x10-10 -1.27477x10-15

R134a/RL68H (99.5/0.5) 

1. 7 K ≤ ∆Ts ≤ 5.6 K -0.213154 6.17060x10-5 -1.31398x10-10 3.94500x10-16

R134a/RL68H (99/1) 

0.6 K ≤ ∆Ts ≤ 6.0 K -0.248401 7.09353x10-5 -1.78672x10-10 4.35663x10-16

R134a/1AlO (99.5/0.5) 

0.4 K ≤ ∆Ts ≤ 5.2 K -0.190960 5.09350x10-5 -3.05821x10-11 2.50653x10-17

R134a/1AlO (99/1) 

0.4 K ≤ ∆Ts ≤ 5.8 K -0.129380 5.59308x10-5 -3.59544x10-11 5.52927x10-17

R134a/2AlO (99/1) 

0.4 K ≤ ∆Ts ≤ 5.8 K -0.117681 5.47738x10-5 3.14180x10-11 -4.54983x10-16

R134a/5AlO (99/1) 

0.8 K ≤ ∆Ts ≤ 6.7 K -0.182003 7.63341x10-5 -1.07500x10-10 -7.00023x10-17
31

Table 5 Residual standard deviation of ∆Ts

Fluid (K)

Pure R134a 

1.6 K ≤ ∆Ts ≤ 5.0 K 0.09

R134a/RL68H (99.5/0.5) 

1. 7 K ≤ ∆Ts ≤ 5.6 K 0.03

R134a/RL68H (99/1) 

0.6 K ≤ ∆Ts ≤ 6.0 K 0.03

R134a/1AlO (99.5/0.5) 

0.4 K ≤ ∆Ts ≤ 5.2 K 0.09

R134a/1AlO (99/1) 

0.4 K ≤ ∆Ts ≤ 5.8 K 0.07

R134a/2AlO (99/1) 

0.4 K ≤ ∆Ts ≤ 5.8 K 0.06

R134a/5AlO (99/1) 

0.8 K ≤ ∆Ts ≤ 6.7 K 0.09
32

Table 6 Average magnitude of 95 % multi-use confidence interval for mean ∆Ts

Fluid U (K)

Pure R134a 

1.6 K ≤ ∆Ts ≤ 5.0 K 0.06

R134a/RL68H (99.5/0.5) 

1. 7 K ≤ ∆Ts ≤ 5.6 K 0.01

R134a/RL68H (99/1) 

0.6 K ≤ ∆Ts ≤ 6.0 K 0.01

R134a/1AlO (99.5/0.5) 

0.4 K ≤ ∆Ts ≤ 5.2 K 0.03

R134a/1AlO (99/1) 

0.4 K ≤ ∆Ts ≤ 5.8 K 0.02

R134a/2AlO (99/1) 

0.4 K ≤ ∆Ts ≤ 5.8 K 0.01

R134a/5AlO (99/1) 

0.8 K ≤ ∆Ts ≤ 6.7 K 0.03
33

Fig. 1 Schematic of test apparatus
34

Fig. 2 OFHC copper flat test plate with Turbo-BII-HP surface and thermocouple 

coordinate system
35

Fig. 3 Photograph of Turbo-BII-HP surface
36

Fig. 4 TEM of Al2O3 nanolubricant (Sarkas, 2009)
37

Fig. 5 Pure R134a boiling curve for Turbo-BII-HP
38

Fig. 6 R134a/RL68H mixtures boiling curves for Turbo-BII-HP
39

Fig. 7 Boiling heat flux of R134a/RL68H mixture relative to that of pure R134a for 

Turbo-BII-HP
40

Fig. 8 R134a/RL68AlO mixtures boiling curves for Turbo-BII-HP
41

Fig. 9 Boiling heat flux of R134a/nanolubricant mixtures relative to that of 

R134a/RL68H without nanoparticles for Turbo-BII-HP
42

Fig. 10 Absolute number of nanoparticles determines average heat transfer 

enhancement for three different surfaces
43

Fig. 11 Comparison of predicted to measured heat flux ratio for four different 

refrigerant/nanolubricant mixtures boiling on a Turbo-BII-HP
44

APPENDIX A: UNCERTAINTIES

Figure A.1 shows the relative (percent) uncertainty of the heat flux (Uq") as a function of 

the heat flux. Figure A.2 shows the uncertainty of the wall temperature as a function of 

the heat flux. The uncertainties shown in Figs. A.1 and A.2 are "within-run 

uncertainties." These do not include the uncertainties due to "between-run effects" or 

differences observed between tests taken on different days. The "within-run 

uncertainties" include only the random effects and uncertainties associated with one 

particular test. All other uncertainties reported in this study are "between-run 

uncertainties" which include all random effects such as surface past history or seeding. 

Fig. A.1 Expanded relative uncertainty in the heat flux of the surface at the 95 % 

confidence level
45

Fig. A.2 Expanded uncertainty in the temperature of the surface at the 95 % 

confidence level