• 제목/요약/키워드: 윅

검색결과 94건 처리시간 0.032초

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
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    • 대한기계학회 2007년도 춘계학술대회B
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    • pp.2130-2135
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    • 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.

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히트파이프용 소결윅의 제작과정 및 특성 (Manufacturing Procedure and Characteristic of Sintered Wick for Heat Pipe)

  • 윤호경;문석환;황건;최태구
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2001년도 춘계학술대회논문집D
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    • pp.365-370
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    • 2001
  • There are various wick types for heat pipe. In the present study, the manufacturing technology of a sintered wick among various wick types is discussed. The sintering technology using metal has been applied broadly in the field of electronic-telecommunication as well as heat pipes. A study of manufacturing procedure and characteristic of sintered wick for heat pipe have been performed. Copper powder was used as wick material and stainless steel as a mandrel. A manufacturing technology of the mandrel for arranging vapor core in heat pipe, a sintering technology by first or second times and operating temperature for sintering, the measurements of a porosity, pore size, and pore distribution of sintered wick were considered. In the meantime, a heat pipe with sintered wick has been manufactured and a performance test of the heat pipe has been performed in order to review cooling performance. The performance test results for the 4mm diameter heat pipe with the sintered wick shows the stability since the temperature difference between a evaporator and a condenser of the heat pipe is less than $4.4^{\circ}C$, and thermal resistance is less than $0.7^{\circ}C/W$.

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마이크로 세라믹 윅을 사용한 루프 히트파이프의 특성 연구 (Characteristic Studies on Loop Heat Pipe with Micro Ceramic Wick)

  • 박종찬;이충구;이석호
    • 대한기계학회논문집B
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    • 제31권10호
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    • pp.823-831
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    • 2007
  • This paper presents the experimental and simulation study of a loop heat pipe (LHP) that can be applied to present electronics, space missions and thermal control systems. The present experimental study was carried out employing sintered alumina ceramic wick ($d=2.96\;{\mu}m$, ${\phi}=0.61$). High purity R-134a, R-22 and water were also used as alternative working fluids in addition to ammonia. The experimental study showed that the maximum heat transfer performance for the test LHP in the vertical top heating mode was over 100 Watts when ammonia was used as the working fluid. The simulation results have been compared with the experimental results to validate a simulation model based on the thermal resistance network that was developed to evaluate the performance of LHPs, focusing on their prospective applications in electronics. The simulation model is based on the loop overall energy, mass, and momentum balance. The simulation program can predict the effects of various parameters which affect the performance of LHP within 5% compared with the experimental results.

복수버퍼를 가진 다단상호연결네트웍의 비균일 트래픽 환경하에서의 해석적 모델링 (Performance Evaluation of Multibuffered Multistage Interconnection Networks under Nonuniform Traffic Pattern)

  • 문영성
    • 인터넷정보학회논문지
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    • 제5권1호
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    • pp.41-49
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    • 2004
  • 다단상호연결네트윅의 성능평가시 실제적인 환경을 고려하기 위하여는 비균일 트래픽이 존재할 때 및 복수버퍼를 가질 때의 성능평가가 필수적이나 기존의 비균일트래픽하에서의 연구는 입력버퍼의 경우보다 상대적으로 모델링이 쉬운 출력버퍼를 가지고 있을 때를 고려한다든가 블럭킹 상태를 고려하지 못한다든, 단일버퍼만 고려한다든가 하는 결점을 가지고 있다. 따라서 본 논문에서는 입력버퍼를 가진 밴연형 다단상호연결네트윅이 비균일트래픽하에서 모델링하고 성능평가를 하는데 특히 다중의 입력버퍼를 가졌을 경우를 해석적으로 모델링하고 그 모델로부터의 결과와 시뮬레이션으로부터의 결과를 비교하여 구해진 모델의 우수성을 입증한다.

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원판형 LHP 증발부의 소결 금속 윅에서의 접촉 저항에 관한 연구 (A Study on the Reduction the Thermal Contact Resistances at the Interface Between a Porous Metal Wick and Solid Heating Plate for a Circular Plate LHP)

  • 조정래;최지훈;성병호;기재형;유성열;김철주
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2008년도 추계학술대회B
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    • pp.2357-2362
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    • 2008
  • LHP is different from a conventional heat pipes in design and heat and fluid flow passages. The situations of the former is much complex than the latter. In LHPs, evaporation occurs at the contact interface between the heating plate and the porous wick, so some micro channels machined at the contact interface serve to let the vapor flow out of the evaporator. This complexity of contact geometry was known to cause a high resistance to heat flow. The present work was to study the problem of heat passage across the contact surface for LHPs and determine those values contact resistance. For two cases of contact structures, the thermal contact resistances were examined experimentally, one being obtained through mechanical contact under pressure and the other through sintered bonding. Nickel powder wick and copper plate were used for specimens. The result showed that a substantial reduction of contact resistance of an order of degree could be obtainable by sintered bonding.

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존 카메론 밋첼의 영화 <헤드윅>에 나타난 복식에 관한 연구 (A Study on the Costumes expressed in the John Cameron Mitchell's Movie )

  • 서은혜;김혜정
    • 패션비즈니스
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    • 제16권2호
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    • pp.163-179
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    • 2012
  • Among diverse cultural types which can be shown in movie, 'Subculture' is young culture that resist to major culture. It shows its belief and identity via its own style. Their 'Subcultural Style' became popular with mass media and has been affected to major cultures. Therefore, in this research, with times background as postmodernism in end of 20th century and mainly with movie which is about sexual minorities, I analyzed categories of costumes in the movie. Hedwig's rock costume shows combined fashion with hippie, punk, glam, kitsch, goth styles from the impact of postmodernism in mid 20th century. Tommy, showed his relief and defiant intention against old generations with grunge casual and graffiti styles. After he realized Hedwig's identity and showed defiant goth rock style as a famous rocker. The band, "Angry Inch", showed dissatisfaction and cynical attitude against the American society through subculture styles. Through this research, the fact that movie costume used a tool to show human's identity and value. Also, I can see that movie costume shows times and cultural phenomenon in the end of 20th century and through this, it was confirmed that this contributes to crease new fashion style through them.