• 제목/요약/키워드: 루프히트파이프

검색결과 35건 처리시간 0.045초

평판형 증발부를 갖는 루프히트파이프에 대해 박막이론을 적용한 해석적 모델링 (Analytical Modeling of a Loop Heat Pipe with a Flat Evaporator by Applying Thin-Film Theory)

  • 정의국;부준홍
    • 대한기계학회논문집B
    • /
    • 제34권12호
    • /
    • pp.1079-1085
    • /
    • 2010
  • 평판형 증발부를 갖는 루프히트파이프(LHP)에 대한 정상상태 해석모델을 제시하였다. 관련문헌의 고찰에 기초하여 LHP 의 주요 부분인 증발부, 액체저장조(보상챔버), 증기이송관, 액체이송관 및 응축부에서 온도와 압력을 예측할 수 있도록 계산과정을 제시하였으며, LHP 에서 유일하게 모세관 구조물을 가지는 증발부의 해석에 중점을 두었다. 증발부에서 액체 -기체 경계면 부근에서 압력과 온도의 영향을 고려하기 위해 박막이론을 사용하였으며, 수정된 기체분자운동이론에서 응축경계면 온도를 산정하는데 있어서 독특한 방법을 도입하였다. 응축부에서는 상변화 경계면을 단순화하여 처리함으로써 응축부 형상 변화에 상대적인 융통성을 구비하도록 하였다. 본 연구의 LHP 정상상태 해석 모델은 문헌 상의 실험결과에 의해 타당성이 증명되었다. 해석모델에 의한 예측치는 실험치와 비교할 때 절대온도를 기준으로 최대 상대오차 3% 이내로서 합리적으로 잘 일치하였다.

다공성소결윅구조에 따른 루프 히트파이프에서 압력손실의 이론적 분석 (Theoretical Analysis of the Pressure Drop in Loop Heat Pipe by Sintered Porous Wick Structure)

  • 이기우;이욱현;박기호;이계중;전원표;인현만
    • 대한기계학회:학술대회논문집
    • /
    • 대한기계학회 2004년도 춘계학술대회
    • /
    • pp.1225-1230
    • /
    • 2004
  • In this paper, the pressure drops were investigated according to the sintered porous wick structure in loop heat pipe(LHP) by theoretical analysis. LHP has the wick only in evaporator for the circulation of working fluid, so utilizes porous wick structure which pore diameter is very small for large capillary force. This paper investigates the effects of different parameters on the pressure drops of the LHP such as particle diameter of sintered porous wick, wick porosity, vapor line diameter, thickness of wick and heating capacity. Working fluid is water and the material of sintered porous wick is copper. According to the these different parameters, capillary pressure, pressure drop in wick were analized by theoretical design method of LHP.

  • PDF

Non-inverted Meniscus식 모세관 구조물을 이용한 소형 루프히트파이프에 관한 실험적 연구 (A Study on the Miniature Loop Heat Pipe with Non-inverted Meniscus type Capillary Structure)

  • 정원복;박수용
    • 대한기계학회:학술대회논문집
    • /
    • 대한기계학회 2007년도 춘계학술대회B
    • /
    • pp.2142-2147
    • /
    • 2007
  • Experimental study was conducted to evaluate the performance of a miniature loop heat pipe (MLHP) with non-inverted meniscus type capillary structure. All parts of MLHP in this study were made of copper including the capillary structure and the distilled water was used as a working fluid of MLHP. The outer diameter of evaporator was 9 mm and its length was 119 mm. The effective pore size of the capillary structure was 30 micron and its porosity was 60%. The vapor transport line, the liquid transport line and the condenser were consisted of single 4.0 mm copper tube. The distance between the evaporator and the condenser region was 200 mm and the length of the loop was 969 mm. This MLHP was operated successfully at any orientation but the gravity highly influenced the thermal performance of the MLHP. The maximum thermal load was 130 watts at the bottom heat mode and the 20 watts at the top heat mode.

  • PDF

소결금속 윅과 메탄올을 사용하며 바이패스라인이 부착된 루프히트파이프의 작동 특성 (Operating Characteristics of a Sintered-Metal Wick/Methanol Loop Heat Pipe Having a Bypass Line)

  • 부준홍;정의국
    • 대한기계학회:학술대회논문집
    • /
    • 대한기계학회 2007년도 춘계학술대회B
    • /
    • pp.2130-2135
    • /
    • 2007
  • Operating characteristics of a loop heat pipe (LHP) having a bypass line was investigated experimentally. The LHP had a sintered metal wick as a capillary structure and methanol as a working fluid. The sintered metal wick was made of stainless steel of which the average pore size was 5 ${\mu}m$and porosity of 47%. A bypass line of a small diameter was attached between the vapor escape passage and the liquid reservoir. The dimension of the flat evaporator was $50(L){\times}40(W){\times}30(H)$ mm and that of the condenser was $50(L){\times}40(W){\times}11(H)$ mm. Wall and pipe material of the LHP was stainless steel and heating area was 35(W) mm${\times}$35(L) mm. The inner diameters of vapor and liquid transport lines were 4.0 mm and 2.0 mm, and the lengths of the two lines were both 0.5 m. The LHP was tested for three different tilt angles of horizontal, favorite tilt, and adverse tilt. The thermal load range was up to 290 W at the condenser above evaporation position. Furthermore, the effect of a bypass line on the start-up transient as well as steady-state operation was presented and discussed.

  • PDF

지상용 소형 루프히트파이프 성능에 관한 연구 (Thermal Performance of a Small-scale Loop Heat Pipe for Terrestrial Application)

  • 정원복;부준홍
    • 대한기계학회:학술대회논문집
    • /
    • 대한기계학회 2004년도 추계학술대회
    • /
    • pp.1052-1057
    • /
    • 2004
  • A small-scale loop heat pipe with polypropylene wick was fabricated and tested for its thermal performance. The container and tubing of the system was made of stainless steel and several working fluids were used to see the difference in performance including methanol, ethanol, acetone, R134a, and water. The heating area was 35 mm ${\times}$ 35 mm and there were nine axial grooves in the evaporator to provide a vapor passage. The pore size of the polypropylene wick inside the evaporator was varied from 0.5 m to 25 m. The size of condenser was 40 mm (W) ${\times}$ 50 mm (L) in which ten coolant paths were provided. The inner diameter of liquid and vapor transport lines were 2.0 mm and 4.0 mm, respectively and the length of which were 0.5 m. The PP wick LHP was operated with methanol, acetone, and ethanol normally. R134a was not compatible with PP wick and water was unsuitable within operating limit of $100^{\circ}C$. The minimum thermal load of 10 W (0.8 W/cm2) and maximum thermal load of 80 W (6.5 W/cm2) were achieved using methanol as working fluid with the condenser temperature of $20^{\circ}C$ with horizontal position.

  • PDF

R141b를 이용한 루프 세관형 히트파이프의 열전달특성 (Heat Transfer Characteristics of Loop Type Capillary Heat Pipe using R141b as a Working Fluid)

  • 김훈;하승만;김탁용;전경환;최재혁;윤석훈
    • 한국마린엔지니어링학회:학술대회논문집
    • /
    • 한국마린엔지니어링학회 2005년도 후기학술대회논문집
    • /
    • pp.256-257
    • /
    • 2005
  • This paper has been carried out to investigate heat transfer characteristics of loop type capillary heat pipe using R141b as a working fluid. In an experiment heat load are changed from 50W to 250W and the temperature of cooling water is fixed to 20$^{circ}C$ . The heat pipe is composed of 10 turns and outer diameter of heat pipe is 3.2mm. The results show that heat transport rate of this type heat pipe using R141b as a working fluid is good.

  • PDF

루프형 히트파이프를 이용한 LED 헤드램프 열적 특성 (LED Headlamp Thermal Characteristics by Looped Heat Pipe)

  • 노형철;박경석;강병도;손성만
    • 한국정밀공학회:학술대회논문집
    • /
    • 한국정밀공학회 2006년도 춘계학술대회 논문집
    • /
    • pp.443-444
    • /
    • 2006
  • The influence of the heat sources on LED junction temperature are Engine room air, Back plate, Electric power device, and so on. LED lamp cooling system is considered to be an important subject fur high light efficiency. Because LED Chip will be problem When LED junction temperature be over $135^{\circ}C$, In this Study, The Looped Heat Pipe System is considered to prevent LED Chip fall. The LHPS is consist of evaporator part, condenser part, heat pipe part. The working fluid of LHPS is HCFC-123. In this study, to prevent LED Chipfall, we study thermal characteristics for Looped Heat Pipe System with LED lamp.

  • PDF