Design & Manufacturing

  • 제13권2호
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  • Pages.37-43
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  • 2019
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  • 2800-0323(pISSN)
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  • 2733-452X(eISSN)
한국금형공학회 (Korean Society of Die & Mold Engineering)
권호 표지

비공비 혼합냉매 R-410A를 적용한 납작한 알루미늄 마이크로 멀티 튜브에서의 마찰손실에 관한 연구

A study on the friction head loss in flat aluminum micro multi tubes with nonazeotropic refrigerant mixtures R-410A

  • 이정근 ((사)한국에너지기술인협회) ;
  • 민경호 (한국폴리텍대학 인천캠퍼스 기계시스템과)
  • Lee, Jeong-Kun (Korea Energy Engineers Association) ;
  • Min, Kyung-Ho (Department of Mechanical System, Incheon Campus of Korea Polytechnic)
  • 투고 : 2019.05.21
  • 심사 : 2019.06.30
  • 발행 : 2019.06.30
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초록

This study conducted a research as to condensation heat transfer friction loss headby using three types of flat micro multi-channel tubes with different processing of micro-fin and number of channels inside the pipes and different sizes of appearances. In addition, identical studies were conducted by using smoothing circular tubes with 5mm external diameter to study heat enhancement factor and pressure drop penalty factor. 1) The friction head loss showed an increase as the vapor quality and mass flux increased. In case of saturation temperature, it shows an increase as it gets lower. These factors are the reason occurring as the lower the saturation temperature is, the higher the density of refrigerant vapor gets. The influence of heat flux is similar as the dryness is low, but as it gets higher, it lowers in heat flux, and as the high temperature of high heat flux, it is a factor that occurs as the density gets lower. 2) RMS error of the in case of friction head loss, it showed to be predicted as 0.45~0.67 by Chisholm, Friedel, Lockhart and Martinelli. 3) As forfriction head loss penalty factor, the smaller the aspect ratio is, the larger the penalty factor gets, and as for the effect of micro-fin, the penalty factor increased because it decreases to the gas fluid the way groove for the refrigerant's flow.

키워드

참고문헌

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