ǫǰǡǟVol. 2: )3125*Ą32ġ37ူᆔळȤɢɍ৐ᆔळʯ˄Ĝʠૺ༂ৄࠓࡉɅȤȫɥ
GD.83 ᆔ຦ဖຣɅ࠲ȳɥॸ࢞32୪ὶᆺ࠾ࡼࡧྥὶᆺࣉ࣮ࣞࢺᘧ⇕஺᥮ჾ࡟࠾ࡅࡿ FC-72 ὶືἛ㦐࡟㛵ࡍࡿ◊✲ᑠᒣ ᖾᖹ*1㸪୰ᮧ ཭ဢ*2㸪᭷㤿 ༤ྐ*1
Investigation on FC-72 Flow Boiling in Parallel- and Counter-flow Plate Heat Exchangers
Kohei KOYAMA*1 Yuya NAKAMURA*2, and Hirofumi ARIMA*1*1
Institute of Ocean Energy, Saga University
1-48 Hirao, Kubara-aza, Yamashiro-cho, Imari, Saga 849-4256*2

Department of Mechanical Engineering, Saga University
1 Honjo-machi, Saga, 840-8502

This study investigates FC-72 flow boiling in a plate heat exchanger. Bubble behavior and flow pattern in the heatexchanger are directly visualized. The heat exchanger is tested as parallel- and counter-flow configurations to compare
hydraulic and thermal performances. Experimental result shows that the region of churn flow in parallel-flow heatexchanger is wider than that on counter-flow one. Overall heat transfer coefficient of the parallel-flow plate heatexchanger is larger than that of counter-flow one due to destruction of thermal boundary layer. The results mean that
configuration of plate heat exchanger with flow boiling affects its performances.
Key Words : Heat exchanger, Boiling, Flow pattern, Heat transfer enhancement, Visualization

1. ⥴   ゝᣢ⥆ྍ⬟࡞♫఍ࢆᵓ⠏ࡍࡿࡓࡵ㸪෌⏕ྍ⬟࢚ࢿࣝࢠ࣮࡬ࡢ♫఍ⓗ㛵ᚰࡀ㧗ࡲࡗ࡚࠾ࡾ㸪ࡑࡢ୰࡛ࡶ㸪ᾏὒࡸἨ࡞࡝࡟Ꮡᅾࡍࡿᑠ ᗘᕪࢆ฼⏝ࡍࡿⓎ㟁ᢏ⾡ࡀᮇᚅࡉࢀ࡚࠸ࡿ㸬ᑠ ᗘᕪ฼⏝Ⓨ㟁࡟࠾࠸࡚ࡣ㸪࣏ࣥࣉ㸪⇕஺᥮ჾ㸦⵨Ⓨჾ㸧㸪ࢱ࣮ࣅࣥ㸪จ⦰ჾࢆ୺࡞ᵓᡂせ⣲࡜ࡍࡿࢩࢫࢸ࣒ෆࢆసືὶయࡀᚠ⎔ࡋ㸪ࢱ࣮ࣅࣥ࡟㐃⤖ࡉࢀࡓⓎ㟁ᶵ࡛Ⓨ㟁ࢆ⾜࠺㸬ᑠ ᗘᕪⓎ㟁ᑟධಁ㐍ࡢࡓࡵ࡟ࡣ㸪౑⏝ࡍࡿ⇕஺᥮ჾࢆᑠᆺ໬㸪㧗ຠ⋡໬ࡋ㸪Ⓨ㟁ࢩࢫࢸ࣒඲యࡢࢥࢫࢺࢆୗࡆࡿࡇ࡜ࡀ㟂せ࡛࠶ࡿ㸬ᑠ ᗘᕪⓎ㟁ࡢ⵨Ⓨჾ࡟࠾࠸࡚ࡣ㸪⇕஺᥮ຠ⋡ࡸ࣓ࣥࢸࢼࣥࢫᛶࡢほⅬ࡛᭷฼࡞ࣉ࣮ࣞࢺᘧ⇕஺᥮ჾࡀ⏝࠸ࡽࢀࡿ㸬Hsieh ࡽ(1) 㸪Gasparella(2, 3)㸪Táboas ࡽ(4)࡞࡝ࡣ㸪ࣉ࣮ࣞࢺᘧ⇕஺᥮ჾ࡟ᑐࡍࡿᐇ㦂ࢆ⾜࠸㸪ᇶᮏⓗ࡞ఏ⇕≉ᛶࡢゎ᫂ࡸ㸪సືὶయ㉁㔞ὶ᮰㸪ຍ⇕⇕ὶ᮰࡞࡝ࡢ㐠㌿᮲௳ࡀఏ⇕≉ᛶ࡟୚࠼ࡿᙳ㡪࡟ࡘ࠸᳨࡚ウࡋ࡚࠸ࡿ㸬ࣉ࣮ࣞࢺᘧ⇕஺᥮ჾࡣ㸪ᚑ᮶㸪సືὶయ࡜㸪సືὶయࢆຍ⇕ࡍࡿ Ỉ࡜ࡀᑐྥࡋ࡚ὶࢀࡿྥὶᆺࡸ㸪సືὶయ࡜ຍ⇕ࡀ஫࠸࡟┤஺ࡍࡿ┤஺ὶᆺ࡟ࡼࡿ㐠㌿ࡀ᝿ᐃࡉࢀ࡚ࡁࡓ㸬ࡇࢀࡣ㸪Ἓ㦐ࢆకࢃ࡞࠸ࣉ࣮ࣞࢺᘧ⇕஺᥮ჾ࡟࠾࠸࡚㸪ྥὶᆺࡸ┤஺ὶᆺࡢ⇕஺᥮ຠ⋡ࡢ᪉ࡀ㸪సືὶయ࡜ Ỉ࡜ࡀྠࡌ᪉ྥ࡟ὶࢀࡿ୪ὶᆺࡼࡾࡶඃࢀ࡚࠸ࡿ࡜࠸࠺ᚑ᮶ࡢ▱㆑࡟ᇶ࡙ࡃࡶࡢ࡛࠶ࡿ㸬ࡋ࠿ࡋ㏆ᖺ㸪୪ὶᆺࣉ࣮ࣞࢺᘧ⇕஺᥮ჾࡀ㸪௚ࡢᆺᘧ࡜ẚ㍑ࡋ࡚㧗ຠ⋡࡛࠶ࡿ࡜ࡍࡿ◊✲⤖ᯝࡀ Djordjevic ࡽ(5)࡟ࡼࡗ࡚ሗ࿌ࡉࢀࡓ㸬ࡇࢀࡣᚑ᮶ࡢ▱㆑࡜ࡣ┦཯ࡍࡿࡶࡢ࡛࠶ࡿ㸬୍᪉㸪
Djordjevic ࡽ(5)ࡢᐇ㦂⤖ᯝࡣ㸪ࣉ࣮ࣞࢺᘧ⇕஺᥮ჾࡢᆺᘧ࡟ࡼࡗ࡚㸪ࡑࡢఏ⇕≉ᛶࡀ኱ࡁࡃኚ໬ࡍࡿࡇ࡜ࢆ♧၀ࡋ࡚࠸ࡿ㸬ࡇࡇ࡛㸪ࣉ࣮ࣞࢺᘧ⇕஺᥮ჾࡢ⇕ὶືἛ㦐≉ᛶࢆ⌮ゎࡍࡿࡓࡵ࡟ࡣ㸪⇕஺᥮ჾෆ㒊ࢆྍど໬ࡍࡿࡇ࡜ࡀ㔜せ࡜࡞ࡿ㸬ࣉ࣮ࣞࢺᘧ⵨Ⓨჾෆ㒊ࡢྍど໬ࡣ㸪 Baba ࡽ(5)㸪୕ᓥࡽ(6)࡞࡝࡟ࡼࡗ࡚⾜ࢃࢀ࡚࠸ࡿࡀ㸪⇕஺᥮ჾෆ㒊ࡢὶືἛ㦐⌧㇟ࡀ༑ศ࡟⌮ゎࡉࢀࡓ࡜ࡣゝ࠸㞴࠸㸬ཎ✏ཷ௜ 2014 ᖺ 7 ᭶ 31 ᪥
బ㈡኱Ꮫᾏὒ࢚ࢿࣝࢠ࣮◊✲ࢭࣥࢱ࣮㸦ࠛ849-4256 బ㈡┴ఀ୓㔛ᕷᒣ௦⏫ஂཎᏐᖹᑿ 1-48㸧
*2
బ㈡኱Ꮫ ᕤᏛ⣔◊✲⛉ ᶵᲔࢩࢫࢸ࣒ᕤᏛᑓᨷ㸦ࠛ840-8502 బ㈡┴బ㈡ᕷᮏᗉ⏫ 1㸧
E-mail: koyama@ioes.saga-u.ac.jp
**1

33

ழટড়ိ -!ෂഺᄯ੖ -!ᄵ༣གષᮏ◊✲࡛ࡣ㸪
㏱᫂࡞⟂యࢆᣢࡘࣉ࣮ࣞࢺᘧ⇕஺᥮ჾࢆ⏝࠸㸪⵨Ⓨჾෆ㒊ࡢὶືἛ㦐ᵝ┦ࢆྍど໬ࡍࡿ࡜࡜ࡶ࡟㸪୪ὶᆺ࠾ࡼࡧྥὶᆺࣉ࣮ࣞࢺᘧ⇕஺᥮ჾࡢ⇕ὶື≉ᛶࢆẚ㍑ࡍࡿࡇ࡜ࢆ┠ⓗ࡜ࡍࡿ㸬
2. ᐇ   㦂2࣭1 ᐇ㦂⿦⨨
ᅗ 1 ࡟ᐇ㦂⿦⨨ࡢᴫ␎ᅗࢆ♧ࡍ㸬ᅗ 1(a)ࡣྥὶᆺ㸪ᅗ 1(b)ࡣ୪ὶᆺ࡛࠶ࡾ㸪㓄⟶⣔ࢆ⤌ࡳ᭰࠼ࡿࡇ࡜࡛⇕஺᥮ჾࡢᆺᘧࢆኚ᭦ࡍࡿ㸬ᐇ㦂⿦⨨ࡣ㸪సືὶయ㸪 Ỉ࠾ࡼࡧ෭Ỉࡢ 3 ⣔⤫࠿ࡽᵓᡂࡉࢀࡿ㸬సືὶయࡣ࣏ࣥࣉ࡟ࡼࡾᚠ⎔ࡉࡏࡽࢀ㸪ࣉࣞࣄ࣮ࢱ࣮࡛௵ពࡢ ᗘ࡟ㄪ⠇ࡉࢀࡓᚋ㸪⇕஺᥮ჾ࡟౪⤥ࡉࢀࡿ㸬⇕஺᥮ჾ࡛ࡣ㸪⇕※࡛࠶ࡿ Ỉ࡟ࡼࡾຍ⇕ࡉࢀ㸪సືὶయࡀἛ㦐ࡍࡿ㸬Ẽᾮ஧┦ὶ࡛⇕஺᥮ჾ࠿ࡽ᤼ฟࡉࢀࡓసືὶయࡣ㸪ࢱࣥࢡ࡟ᡠࡉࢀ㸪෭Ỉ࡟ࡼࡾ෭༷ࡉࢀࡿࡇ࡜࡛จ⦰ࡋ㸪ᾮ༢┦࡜࡞ࡿ㸬⇕஺᥮ჾࡢᆺᘧࡣ㸪సືὶయ࡜ Ỉ࡜ࡀᑐྥࡋ࡚ὶࢀ
ࡿྥὶᆺ࡜㸪ྠࡌ᪉ྥ࡟ὶࢀࡿ୪ὶᆺ࡟ศ㢮ࡉࢀࡀ㸪ᮏ◊✲࡛ࡣ㸪ࡇࢀࡽ୧ᆺᘧ࡟ᑐࡋ࡚ᐇ㦂ࢆ⾜࠺㸬సືὶయ㉁㔞ὶ㔞ࡢ ᐃ࡟ࡣࢥࣜ࢜ࣜᘧὶ㔞ィ㸦Keyence, FD-SS2A, ±1%F.S.㸧ࢆ㸪 Ỉయ✚ὶ㔞ࡢ ᐃ࡟ࡣ㠃✚ᘧὶ㔞ィ
㸦Kofloc RK1950AP, ±2%F.S.㸧ࢆ⏝࠸ࡿ㸬సືὶయ࠾ࡼࡧ Ỉࡢ ᗘ ᐃ࡟ࡣ T ᆺ⇕㟁ᑐࢆ⏝࠸ࡿ㸬ᅗ2࡟ᮏ◊✲࡛⏝࠸ࡿࣉ࣮ࣞࢺᘧ⇕஺᥮ჾࡢᴫ␎ᅗࢆ♧ࡍ㸬⇕஺᥮ჾࡣ㸪సືὶయഃ࠾ࡼࡧ Ỉഃ࢝ࣂ࣮ࣉ࣮ࣞࢺ㸪ࢸࣇࣟࣥ〇࢞ࢫࢣࢵࢺ࠾ࡼࡧఏ⇕㠃࡛ᵓᡂࡉࢀ㸪ࡑࢀࡽࡀ࣎ࣝࢺ࡛⥾ࡵ௜ࡅࡽࢀࡿ㸬࢝ࣂ࣮ࣉ࣮ࣞࢺ࡟ࡣ㸪⇕஺᥮ჾෆ㒊ࢆྍど໬ࡍࡿࡓࡵ㸪㏱᫂࡞࢔ࢡࣜࣝࢆ⏝࠸ࡿ㸬సືὶయὶ㊰ࡣᖜ150mm㛗ࡉ400mm㧗ࡉ2mm㸪Ỉὶ㊰ࡣᖜ150mm㛗ࡉ400mm㧗ࡉ10mm࡛࠶ࡿ㸬ఏ⇕㠃ࡣࢳࢱࣥ〇࡛㸪ᅗ3࡟♧ࡍࡼ࠺࡟㸪సືὶయഃࡢ⾲㠃࡟ࡣ㸪ఏ⇕ಁ㐍ࢆ┠ⓗ࡜ࡋ࡚㸪┤ᚄ300ȝm㸪㧗ࡉ30ȝmࡢᚤ⣽࡞෇ᰕ≧ࡢࣆࣥࣇ࢕ࣥࡀタࡅࡽࢀ࡚࠸ࡿ㸬TTT

T

FC-72 loop

Hot waterloop

FC-72 loop
1Hot waterloop
11010
TCold waterloop

5TTCold waterloop

75T

7
9

966

82

82
443

3

1. Plate heat exchanger (Test section) 2. Working fluid tank 3. Working fluid pump
4. Mass flow meter 5. Pre-heater 6. Chiller 7. Hot water tank 8. Heater 9. Hot water pump
10. Volumetric flow meter(a) Counter-flow arrangement.

(b) Parallel-flow arrangement.

Fig. 1 Scheatic diagram of experimental setup.
275
Outlet port

40 2 30 10 40150400414

540

Titanium heattransfer plate

Workingfluid

Transparent
acrylic coverplate

Inlet port
Unit: mmFig. 2 Dimension of plate heat exchanger.

Fig. 3. Heat transfer surface with pin-fin.

ူᆔळȤɢɍ৐ᆔळʯ˄Ĝʠૺ༂ৄࠓࡉɅȤȫɥ
GD.83 ᆔ຦ဖຣɅ࠲ȳɥॸ࢞

34ᮏ◊✲࡛ࡣ㸪⇕஺᥮ჾෆ㒊ࡢὶືἛ㦐ᵝ┦ࢆྍど໬ࡍࡿ㸬ࢹࢪࢱ࣓࡛ࣝ࢝ࣛὶືἛ㦐ᵝ┦ࢆ᧜ᙳࡋ㸪ὶືᵝᘧࡢほᐹ࠾ࡼࡧ࣎࢖ࢻ⋡ࡢ ᐃࢆ⾜࠺㸬࣓࢝ࣛ࡟ࡣNikon D800ࢆ㸪ࣞࣥࢬ࡟ࡣAF-S NIKKOR 35mm f/1.4Gࢆ⏝࠸ࡿ㸬᧜ᙳ᫬ࡢࢩࣕࢵࢱ࣮㏿ᗘࡣ1/4000s࡜ࡋࡓ㸬2࣭2 ᐇ㦂᪉ἲᮏ◊✲࡛ࡣ㸪௨ୗࡢᡭ㡰࡟ᚑࡗ࡚ᐇ㦂ࢆ⾜࠺㸬(1) సືὶయ࠾ࡼࡧ෭Ỉࢆᚠ⎔ࡉࡏࡿ㸬(2)ỈࢱࣥࢡෆࡢỈࢆ㸪௵ពࡢ ᗘࡲ࡛ᚎࠎ࡟ຍ⇕ࡋ࡞ࡀࡽᚠ⎔ࡉࡏࡿ㸬ྠ᫬࡟㸪ࣉࣞࣄ࣮ࢱ࣮ࡢ㟁ᅽࢆ㸪సືὶయࡀ௵ពࡢ⇕஺᥮ჾධཱྀ ᗘ࡜࡞ࡿࡼ࠺࡟ㄪ⠇ࡍࡿ㸬(3)ᐃࢹ࣮ࢱࡀ௵ពࡢᐇ㦂᮲௳࡛ᐃᖖ≧ែ࡜࡞ࡗࡓᚋ㸪ࢹ࣮ࢱ࣮ࣟ࢞࡟ࡼࡾ ᐃࢹ࣮ࢱࢆ཰㞟ࡍࡿ㸬(4) ࢹࢪࢱ࣓࡛ࣝ࢝ࣛࣉ࣮ࣞࢺᘧ⇕஺᥮ჾࢆ᧜ᙳࡋ㸪ὶືἛ㦐ᵝ┦ࡢྍど໬⏬ീࢆྲྀᚓࡍࡿ㸬
2࣭3 ⏬ീฎ⌮࠾ࡼࡧ࣎࢖ࢻ⋡⇕஺᥮ჾෆ㒊ࡢὶືἛ㦐ᵝ┦ࢆࢹࢪࢱ࣓࡛ࣝ࢝ࣛ᧜ᙳࡋ㸪ᚓࡽࢀࡓ⏬ീ࡟ᇶ࡙ࡁ㸪సືὶయࡢὶࢀ᪉ྥ࡟ἢࡗࡓ࣎࢖ࢻ⋡ࢆồࡵࡿ㸬⏬ീฎ⌮࠾ࡼࡧ࣎࢖ࢻ⋡ࡢ⟬ฟࡣ㸪௨ୗࡢᡭ㡰࡛⾜࠺㸬(1) ᅗ 4 ࡟♧ࡍࡼ࠺࡟㸪᧜ᙳ࡛ᚓࡽࢀࡓ⏬ീ࡟ᑐࡋ࡚㸪Ẽ┦㒊ศࢆⓑⰍ࡟ࡍࡿ⏬ീฎ⌮ࢆ᪋ࡍ㸬(2) ࣃࢵ࢟ࣥ➼㸪సືὶయὶ㊰௨እࡢせ⣲ࢆ๐㝖ࡍࡿ㸬(3) ⏬ീࢆࢢ࣮ࣞࢫࢣ࣮ࣝ࡟ኚ᥮ࡍࡿ㸬(4) సືὶయࡢྛὶࢀ᪉ྥ఩⨨࡟࠾ࡅࡿ࣎࢖ࢻ⋡ࢆ⟬ฟࡍࡿ㸬࣎࢖ࢻ⋡ࡣ㸪ྛ఩⨨࡟࠾ࡅࡿ⏬ീࡢࣆࢡࢭࣝᩘ࡟ᇶ࡙ࡁ㸪ḟᘧ࡟ࡼࡾồࡵࡿ㸬
D N G NT(1)ࡇࡇ࡛㸪NG ࡣ௵ពࡢసືὶయὶ㊰᩿㠃࡟࠾ࡅࡿẼ┦ࡢࣆࢡࢭࣝᩘ㸪NT ࡣࡑࡢ᩿㠃ࡢ඲ࣆࢡࢭࣝᩘ࡛࠶ࡿ㸬

Gas-phase

Liquid-phaseFig. 4. Image processing for two-phase flow.

2࣭4 ⇕㏻㐣⋡ࣉ࣮ࣞࢺᘧ⇕஺᥮ჾࢆ୪ὶᆺ࡜ྥὶᆺ࡛㐠㌿ࡋ㸪⇕㏻㐣⋡ࢆẚ㍑ࡍࡿ㸬⇕㏻㐣⋡ U ࡣḟᘧ࡟ࡼࡾồࡵࡿ㸬(2)
U Q A'Tlmࡇࡇ࡛㸪஺᥮⇕㔞Qࡣḟᘧ࡟ࡼࡾồࡵࡿ㸬࡞࠾㸪ῧ࠼Ꮠwࡣ Ỉࡢ್࡛࠶ࡿࡇ࡜ࢆ♧ࡋ࡚࠸ࡿ㸬Q w c p, w Tw,in  Tw,outm(3)

ࡲࡓ㸪ᑐᩘᖹᆒ ᗘᕪǻTlmࡣḟᘧ࡛ᐃ⩏ࡉࢀࡿ㸬

'TlmTw,in  Tw,outlnTw,in  TsatTw,out  Tsat(4)35ழટড়ိ -!ෂഺᄯ੖ -!ᄵ༣གષ

2࣭5 ᐇ㦂᮲௳୪ὶᆺ࠾ࡼࡧྥὶᆺࣉ࣮ࣞࢺᘧ⇕஺᥮ჾࡑࢀࡒࢀ࡟ᑐࡋ࡚㸪➼ࡋ࠸᮲௳࡛ᐇ㦂ࢆ⾜࠺㸬ᐇ㦂᮲௳ࡣ㸪సືὶయ㉁㔞ὶ᮰ G = 90kg/m2s㸪ᖹᆒ⇕ὶ᮰ q = 3kW/m2㸪⵨Ⓨჾධཱྀ ᗘ T = 52Υ㸪㣬࿴ᅽຊ Psat = 0.1MPa ࡜ࡍࡿ㸬3. ⤖ᯝ࠾ࡼࡧ⪃ᐹ3࣭1 ὶືᵝᘧᅗ 5 ࡟㸪୪ὶᆺࡢᐇ㦂࡛ᚓࡽࢀࡓὶືἛ㦐ᵝ┦ࡢ▐㛫෗┿ࡢ౛ࢆ♧ࡍ㸬ࡇࡇ࡛㸪సືὶయධཱྀࡣ෗┿ྑୗ࡟㸪ฟཱྀࡣᕥୖ࡟఩⨨ࡋ࡚࠾ࡾ㸪సືὶయࡣୗ᪉࠿ࡽୖ᪉࡟ὶࢀ࡚࠸ࡿ㸬ఏ⇕㠃ࢆᣳࢇࡔ⣬㠃ዟഃࢆ⇕※ࡢ Ỉࡀὶࢀ࡚࠾ࡾ㸪୪ὶᆺ࡛ࡣୗ᪉࠿ࡽୖ᪉࡟ὶࢀ࡚࠸ࡿ㸬Ẽᾮ஧┦ὶࡢὶືᵝᘧࡣ㸪ᅗ 6 ࡟♧ࡍࡼ࠺࡟㸪ẼἻὶ㸪ࢫࣛࢢὶ࠾ࡼࡧࢳ࣮ࣕࣥὶࡀほᐹࡉࢀࡓ㸬ఏ⇕㠃ୖࡢసືὶయ ᗘࡀ㣬࿴ ᗘ࡟㐩ࡍࡿ࡜㸪ᅗ 6(a)ࡢࡼ࠺࡟㸪ከᩘࡢⓎἻⅬ࡟࠾࠸࡚᰾Ἓ㦐ࡀ⏕ࡌ㸪⵨ẼẼἻࡀⓎ⏕ࡍࡿ㸬Ⓨ⏕ࡋࡓ⌫ᙧࡢ⵨ẼẼἻࡣ㸪ᾋຊὶࢀ࡜ᾮ┦ࡢసືὶయ࡟ࡼࡗ࡚ఏ⇕㠃ୖ࠿ࡽ㞳ࡉࢀ㸪ୗὶ࡬࡜㐠ࡤࢀࡿ㸬సືὶయࡢὶࢀ࡜࡜ࡶ࡟㸪ᅗ 6(b)ࡢࡼ࠺࡟ẼἻࡣᡂ㛗㸪ྜయࡋ㸪ࡑࡢᙧࡀᘬࡁఙࡤࡉࢀࡿ㸬ࡇࡢ࡜ࡁ㸪ẼἻࡀసືὶయὶ㊰ࡢ῝ࡉ᪉ྥ࡯ࡰࡍ࡭࡚ࢆ༨᭷ࡍࡿࡓࡵ㸪ఏ⇕㠃ୖ࡟ࡣⷧ࠸ᾮ⭷ࡀᏑᅾࡋ࡚࠸ࡿ㸬ᅗ 6(c)ࡢࢳ࣮ࣕࣥὶ࡛
ࡣ㸪ẼἻࡣࡉࡽ࡟኱ࡁࡃ࡞ࡿ࡜࡜ࡶ࡟㸪ẼἻ࡝࠺ࡋࡀ」㞧࡟⾪✺㸪ྜయ㸪ศ⿣ࢆక࠸࡞ࡀࡽὶືࡋ㸪つ๎ᛶࡣᏑᅾࡋ࡞࠸㸬ࡑࡢࡓࡵ㸪సືὶయࡀᙉࡃᨩᢾࡉࢀ㸪ఏ⇕㠃ୖࡢ ᗘቃ⏺ᒙࡀ◚ቯࡉࢀࡿࡇ࡜ࡀ⪃࠼ࡽࢀࡿ㸬(a) Bubbly flow.

(b) Slug flow.

Fig. 5. Instantaneous picture of FC-72
flow boiling in the parallel-flow plate
heat exchanger.

(c) Churn flow.

Fig. 6. Observed two-phase flow pattern.
ᅗ 7 ࡟㸪ྥὶᆺ࠾ࡼࡧ୪ὶᆺ࡟࠾ࡅࡿὶືἛ㦐ࡢ▐㛫෗┿ࢆ♧ࡍ㸬సືὶయධཱྀࡣὶ㊰ྑୗ࡟㸪ฟཱྀࡣᕥୖ࡟఩⨨ࡋ㸪ୗ᪉࠿ࡽୖ᪉࡬ὶࢀࡿ㸬సືὶయࢆຍ⇕ࡍࡿ Ỉࡢὶ㊰ࡣ㸪ఏ⇕㠃ࢆᣳࢇࡔ⣬㠃ዟഃ࡟࠶ࡾ㸪 Ỉࡣ㸪ྥὶᆺ࡛ࡣసືὶయ࡜ᑐྥࡋ࡚ୖ᪉࠿ࡽୗ᪉࡟㸪୪ὶᆺ࡛ࡣసືὶయ࡜ྠᵝ࡟ୗ᪉࠿ࡽୖ᪉࡬౪⤥ࡉࢀࡿ㸬ᅗ 7(a)ࡢྥὶᆺ࡟࠾࠸࡚㸪⇕஺᥮ჾ࡟ᾮ༢┦࡛ධࡗࡓసືὶయࡣ㸪 Ỉ࠿ࡽཷࡅࡿ⇕࡛ຍ⇕ࡉࢀ㸪᰾Ἓ㦐ࢆ㛤ጞࡍࡿ㸬ྥὶᆺ࡛ࡣ㸪 Ỉࡣ෗┿ࡢୖ᪉࠿ࡽୗ᪉࡟౪⤥ࡉࢀࡿࡓࡵ㸪ఏ⇕㠃⾲㠃ࡢ ᗘࡣసືὶయฟཱྀ௜㏆ࡀ᭱ࡶ㧗ࡃ㸪సືὶయධཱྀ௜㏆ࡀ᭱ࡶప࠸㸬ࡑࡢࡓࡵ㸪᰾Ἓ㦐㛤ጞ࡟⮳ࡿࡲ࡛ࡢ⁫␃᫬㛫ࡀ㛗ࡃ㸪ⓎἻⅬࡀసືὶయୗὶഃ࡟ከࡃᏑᅾࡍࡿࡶࡢ࡜⪃࠼ࡽࢀࡿ㸬Ⓨ⏕ࡋࡓ⵨ẼẼἻࡣ㸪஫࠸࡟ᖸ΅ࡋ࡞ࡀࡽᡂ㛗㸪ྜయࡋ㸪ὶ㊰ෆࡢసືὶయࢆ⃭ࡋࡃ᧠ᢾࡋ࡚࠸ࡿ㸬ࡲࡓ㸪ᕥྑࡢ࢞ࢫࢣࢵࢺ࠿ࡽࡶẼἻࡀⓎ⏕ࡋ㸪సືὶయὶ㊰ୗὶࡢἛ㦐ᵝ┦࡟ᙳ㡪ࢆ୚࠼࡚࠸ࡿ㸬ࡇࢀࡣ㸪࢞ࢫࢣࢵࢺࢆຍᕤࡋࡓ㝿࡟࡛ࡁࡓᚤ⣽࡞⾲㠃ᵓ㐀ࡀⓎἻⅬ࡜࡞ࡗࡓࡇ࡜࡟ࡼࡿࡶࡢ࡜⪃࠼ࡽࢀ㸪࢞ࢫࢣࢵࢺࢆ⏝࠸ࡿࣉ࣮ࣞࢺᘧ⇕஺᥮ჾ≉᭷ࡢ⌧㇟࡜࠸࠼ࡿ㸬Ẽᾮ஧┦ὶࡢὶືᵝᘧࡣ㸪సືὶయࡢὶࢀ࡟ἢࡗ࡚㸪ẼἻὶ㸪ࢫࣛࢢὶ㸪ࢳ࣮ࣕࣥὶ࡟ศ㢮ࡉࢀࡿ㸬ူᆔळȤɢɍ৐ᆔळʯ˄Ĝʠૺ༂ৄࠓࡉɅȤȫɥ
GD.83 ᆔ຦ဖຣɅ࠲ȳɥॸ࢞

36

ᅗ 7(b)ࡢ୪ὶᆺ࡛ࡣ㸪సືὶయୖὶഃ࡟ⓎἻⅬࡀከᩘᏑᅾࡋ࡚࠸ࡿ㸬ࡇࢀࡣ㸪୪ὶᆺࡢሙྜ㸪సືὶయࢆຍ⇕ࡍࡿ Ỉࡣ㸪ᅗࡢୗ᪉࠿ࡽୖ᪉࡟౪⤥ࡉࢀࡿࡓࡵ㸪సືὶయධཱྀ௜㏆ࡢఏ⇕㠃 ᗘࡀ༑ศ࡟㧗ࡃ㸪▷࠸⁫␃᫬㛫࡛᰾Ἓ㦐ࢆ㛤ጞࡋࡓࡇ࡜࡟ࡼࡿ࡜⪃࠼ࡽࢀࡿ㸬୪ὶᆺࡢⓎἻⅬࡀୖὶഃ࡟఩⨨ࡍࡿࡓࡵ㸪ᡂ㛗㸪ྜయ࡞࡝ẼἻࡢᣲືࡢᙳ㡪ࡀཬࡪ⠊ᅖࡀᗈࡃ㸪సືὶయ᧠ᢾࡢຠᯝࡀᙉ࠸ࡇ࡜ࡀࢃ࠿ࡿ㸬୪ὶᆺ࡟࠾࠸࡚ࡶ㸪ྥὶᆺ࡜ྠᵝ㸪Ẽᾮ஧┦ὶࡢὶືᵝᘧࡣ㸪ẼἻὶ㸪ࢫࣛࢢὶ࠾ࡼࡧࢳ࣮ࣕࣥὶ࡟ศ㢮ࡉࢀࡿࡀ㸪ྥὶᆺ࡜ẚ࡭࡚ẼἻὶࡢ㡿ᇦࡀ⊃ࡃ㸪ࢳ࣮ࣕࣥὶࡢ㡿ᇦࡀᗈ࠸㸬ࡇࢀࡣ㸪ⓎἻⅬࡀసືὶయୖὶഃ࡟ከᩘᏑᅾࡍࡿࡇ࡜࡟ࡼࡿࡓࡵ࡜⪃࠼ࡽࢀࡿ㸬3࣭2 ࣎࢖ࢻ⋡ᅗ 8 ࡟㸪
ᅗ 7 ࡛♧ࡋࡓ⏬ീ࠿ࡽồࡵࡓ୪ὶᆺ࠾ࡼࡧྥὶᆺࡢసືὶయὶࢀ᪉ྥ࡟ἢࡗࡓ࣎࢖ࢻ⋡ࢆ♧ࡍ㸬࡞࠾㸪ࢢࣛࣇࡢᶓ㍈ࡣ㸪సືὶయධཱྀ㒊ศࢆᇶ‽㧗ࡉ㸦z = 0 mm㸧࡜ࡋ㸪సືὶయࡢὶࢀ᪉ྥ࡟ἢࡗࡓ㊥㞳࡛࠶ࡿ㸬࠸ࡎࢀ࡟࠾࠸࡚ࡶ㸪᰾Ἓ㦐ࡢ㛤ጞ࡟క࠸⵨ẼẼἻࡀⓎ⏕ࡋ㸪࣎࢖ࢻ⋡ࡀୖ᪼ࡋ࡚࠸ࡿ㸬సືὶయࡢὶࢀ࡜࡜ࡶ࡟ẼἻࡀᡂ㛗㸪ྜయࡋ㸪ẼἻࢧ࢖ࢬࡀ኱ࡁࡃ࡞ࡿࡇ࡜࡛㸪࣎࢖ࢻ⋡ࡀᛴ⃭࡟ቑຍࡋ࡚࠸ࡿ㸬୪ὶᆺ࡛ࡣ㸪ᅗ 7 ࡟♧ࡍࡼ࠺࡟㸪ⓎἻⅬࡀྥὶᆺࡼࡾࡶసືὶయୖὶഃ࡟Ꮡᅾࡍࡿࡓࡵ㸪ୖὶഃ࡟࠾ࡅࡿ࣎࢖ࢻ⋡ࡀ኱ࡁࡃ࡞ࡗ࡚࠸ࡿ㸬ࡑࡢࡓࡵ㸪ࡇࡢ㡿ᇦ࡛ࡣ㸪ẼἻ࡟ࡼࡗ࡚ὶࢀࡀᨩᢾࡉࢀ㸪ఏ⇕㠃ୖࡢ ᗘቃ⏺ᒙࡀ◚ቯࡉࢀ࡚࠸ࡿࡇ࡜ࡀ᥎ᐹ࡛ࡁ㸪⇕஺᥮ჾࡢᆺᘧ࡟ࡼࡗ࡚ఏ⇕≉ᛶ࡟ᕪ␗ࡀ⏕ࡌࡿࡇ࡜ࡀ⪃࠼ࡽࢀࡿ㸬

Churn flow

Slug flow

Churn flow

Bubbly flow
Slug flow

Bubbly flow(a) Counter-flow arrangement.

(b) Parallel-flow arrangement.

0.8

0.8

0.6

0.6

0.40.4ĮĮFig. 7. Classifications of flow pattern.

0.20.20.0

0.00100200z (mm)300(a) Counter-flow arrangement.

4000100200z (mm)

300

400

(b) Parallel-flow arrangement.

Fig. 8. Void fraction along direction of FC-72 fluid flow.

37ழટড়ိ -!ෂഺᄯ੖ -!ᄵ༣གષ

300

ᅗ 9 ࡟㸪ᮏᐇ㦂᮲௳࡟࠾ࡅࡿ୪ὶᆺ࡜ྥὶᆺࡢ⇕㏻㐣
⋡ࢆ♧ࡍ㸬⇕㏻㐣⋡ࡣ㸪ྥὶᆺ࡟ẚ࡭࡚୪ὶᆺࡢ᪉ࡀ⣙6%኱ࡁࡃ㸪ࡇࡢഴྥࡣ Djordjevic ࡽ(5)ࡢ⤖ᯝ࡜ᑐᛂࡋ࡚
࠸ࡿ㸬୪ὶᆺ࡛ࡣྥὶᆺ࡟ẚ࡭࡚ࢳ࣮ࣕࣥὶࡢ㡿ᇦࡀᗈࡃ㸪᰾Ἓ㦐㛤ጞⅬࡀసືὶయୖὶഃ࡟఩⨨ࡋ࡚࠸ࡿ㸬ࡑ

U (W/m2K)

3࣭3 ⇕㏻㐣⋡275
250
225

ࡢࡓࡵ㸪ẼἻ࡟ࡼࡗ࡚సືὶయࡢὶࢀࡀᙉࡃ᧠ᢾࡉࢀ㸪ᗘቃ⏺ᒙࡀ◚ቯࡉࢀࡓࡇ࡜࡟㉳ᅉࡍࡿ࡜⪃࠼ࡽࢀࡿ㸬௨ୖࡢ⤖ᯝࡣ㸪సືὶయ࡜ Ỉࡢ౪⤥᪉ྥ࡟ࡼࡗ࡚ࣉࣞ
࣮ࢺᘧ⇕஺᥮ჾࡢ⇕ὶື≉ᛶࡀኚ໬ࡍࡿࡇ࡜ࢆព࿡ࡋ࡚
࠸ࡿ㸬

200
Counter-flow

Parallel-flow

Fig. 9. Comparison of overall heat transfer
coefficient4. ⤖   ㄽసືὶయ࡟ FC-72 ࢆ⏝࠸ࡓ୪ὶᆺ࠾ࡼࡧྥὶᆺࣉ࣮ࣞࢺᘧ⇕஺᥮ჾ࡟࠾࠸࡚㸪ὶືἛ㦐ᵝ┦ࡢྍど໬࠾ࡼࡧ⇕㏻㐣⋡ࡢ ᐃࢆ⾜ࡗࡓ㸬ᮏᐇ㦂᮲௳࡟࠾࠸࡚ࡣ㸪୪ὶᆺࡢ᪉ࡀྥὶᆺࡼࡾࡶࢳ࣮ࣕࣥὶࡢ㡿ᇦࡀᗈࡃ࡞ࡿࡇ࡜㸪ࡇࢀ࡟క࠺సືὶయࡢ᧠ᢾຠᯝ࡟ࡼࡾ㸪ఏ⇕㠃ୖ࡟࠾࠸࡚ ᗘቃ⏺ᒙࡀ◚ቯࡉࢀ㸪୪ὶᆺࡢ᪉ࡀྥὶᆺࡼࡾࡶ⇕㏻㐣⋡ࡀ኱ࡁࡃ࡞ࡿࡇ࡜ࢆ᫂ࡽ࠿࡟ࡋࡓ㸬ࡲࡓ㸪ᮏ◊✲ࡢ⤖ᯝࡣ㸪⇕஺᥮ჾࡢᆺᘧ࡟ࡼࡗ࡚ఏ⇕≉ᛶࡀ኱ࡁࡃᙳ㡪ࢆཷࡅࡿࡇ࡜ࢆ♧၀ࡋ࡚࠸ࡿ㸬ᩥ   ⊩(1) Hsieh, Y.Y. and Lin, T.F., “Saturated flow boiling heat transfer and pressure drop of refrigerant R-410A in a vertical plate heatexchanger”, International Journal of Heat and Mass Transfer, Vol. 45 (2002), pp. 1033-1044.
(2) Longo, G.A. and Gasparella, A., “HFC-410A vaporisation inside a commercial brazed plate heat exchanger”, Experimental
Thermal and Fluid Science, Vol. 32 (2007), pp. 107-116.
(3) Longo, G.A. and Gasparella, A., “Refrigerant R134a vaporisation heat transfer and pressure drop inside a small brazed plate
heat exchanger”, International Journal of Refrigeration, Vol. 30 (2007), pp. 821-830.
(4) Táboas, F., Vallès, M., Bourouis, M., and Coronas, A., 2010, “Flow boiling heat transfer of ammonia/water mixture in a plate
heat exchanger”, International Journal of Refrigeration, Vol. 33 (2010), pp. 695-705.
(5) Djordjevic E. and Kabelac, S., “Flow boiling of R134a and ammonia in a plate heat exchanger”, International Journal of Heatand Mass Transfer, Vol. 51 (2008), pp. 6235-6242.
(6) Baba, T., Harada, S., Asano, H., Sugimoto, K., Takenaka, N. and Mochiki, K., “Nondestructive inspection for boiling flow inplate heat exchanger by neutron radiography”, Nuclear Instruments and Methods in Physics Research, Vol.605, No, 1-2 (2009),
pp.142-145.
(7) ୕ᓥᩥஓ㸪᭷㤿༤ྐ㸪ᑠᒣᖾᖹ㸪ᒸᮏ᫂ኵ㸪ụୖᗣஅ㸪࢔ࣥࣔࢽ࢔ᙉไᑐὶࡢࣉ࣮ࣞࢺᘧ⵨Ⓨჾ࡟࠾ࡅࡿἛ㦐ᵝ┦㸪బ㈡኱Ꮫᾏὒ࢚ࢿࣝࢠ࣮◊✲ࢭࣥࢱ࣮ሗ࿌ OTEC㸪Vol.16㸪(2011)㸪pp. 19-32㸬