기관회원 [로그인]
소속기관에서 받은 아이디, 비밀번호를 입력해 주세요.
개인회원 [로그인]

비회원 구매시 입력하신 핸드폰번호를 입력해 주세요.
본인 인증 후 구매내역을 확인하실 수 있습니다.

회원가입
서지반출
Condensation Heat Transfer Coefficients of HCFC22, R410A, R407C and HFC134a at Various Temperatures on a Plain Horizontal Tube
[STEP1]서지반출 형식 선택
파일형식
@
서지도구
SNS
기타
[STEP2]서지반출 정보 선택
  • 제목
  • URL
돌아가기
확인
취소
  • Condensation Heat Transfer Coefficients of HCFC22, R410A, R407C and HFC134a at Various Temperatures on a Plain Horizontal Tube
  • Condensation Heat Transfer Coefficients of HCFC22, R410A, R407C and HFC134a at Various Temperatures on a Plain Horizontal Tube
저자명
Park. Ki-Jung,Jung. Dong-Soo
간행물명
Journal of mechanical science and technology
권/호정보
2007년|21권 5호|pp.804-813 (10 pages)
발행정보
대한기계학회
파일정보
정기간행물|ENG|
PDF텍스트
주제분야
기타
이 논문은 한국과학기술정보연구원과 논문 연계를 통해 무료로 제공되는 원문입니다.
서지반출

기타언어초록

In this study, external condensation heat transfer coefficients (HTCs) of HCFC22, R410A, R407C, and HFC134a were measured on a smooth horizontal tube at 30, 39, and $50^{circ}C$ with the wall subcooling of 3-$8^{circ}C$. The results showed that condensation HTCs decreased for all fluids tested with an increase in temperature. This is due mainly to such properties as the saturated liquid density and liquid thermal conductivity. These properties decrease as the temperature increase and accordingly HTCs decrease. The condensation HTCs of R410A are 9.2${sim}$19.7% higher than those of HCFC22 while those of R134a are 2.5${sim}$10.2% lower than those of HCFC22. Condensation HTCs of R407C, nonazeotropic mixture, are 29.4${sim}$34.3% lower than those of HCFC22. Overall, the HTCs of R407C are much lower than those of HCFC22, HFC134a and R410A due to the mass transfer resistance in a diffusion vapor film. Condensation HTCs of HCFC22 and HFC134a are higher than those calculated by Nusselt’s equation by 7.7${sim}$11.8% and 4.0${sim}$11.1% respectively. On the other hand, HTCs of R407C measured on plain tube, however, are not well predicted by these well-known prediction correlations due to the introduction of mass transfer resistance associated with non-azeotropic mixtures.