브레이징식 동세관내 CO2의 냉각 열전달 특성
Cooling Heat Transfer Characteristics of CO2 in a Brazing Type Small Diameter Copper Tube
1
조회
0
다운로드
0
인용
0
참고문헌
키워드
초록
The cooling heat transfer coefficient of CO2 in a brazing type small diameter tube was investigated experimentally. The main components of the refrigerant loop are a receiver, a CO2 compressor, a mass flow meter, an evaporator and a brazing type small diameter tube as a test section. The mass flux of CO2 is 400~1600 [kg/m2s], the mass flowrate of coolant were varied from 0.15 to 0.3 [kg/s], and the cooling pressure of gas cooler were from 8 to 10 [MPa]. The cooling heat transfer coefficients of the brazing type small diameter copper tube is about 4~11.7% higher than that of the conventional type small diameter copper tube. In comparison with test results and existing correlations, correlations failed to predict the cooling heat transfer coefficient of CO2 in a brazing type small diameter copper tube. therefore, it is necessary to develope reliable and accurate predictions determining the cooling heat transfer coefficient of CO2 in a brazing type small diameter copper tube.
Abstract
The cooling heat transfer coefficient of CO2 in a brazing type small diameter tube was investigated experimentally. The main components of the refrigerant loop are a receiver, a CO2 compressor, a mass flow meter, an evaporator and a brazing type small diameter tube as a test section. The mass flux of CO2 is 400~1600 [kg/m2s], the mass flowrate of coolant were varied from 0.15 to 0.3 [kg/s], and the cooling pressure of gas cooler were from 8 to 10 [MPa]. The cooling heat transfer coefficients of the brazing type small diameter copper tube is about 4~11.7% higher than that of the conventional type small diameter copper tube. In comparison with test results and existing correlations, correlations failed to predict the cooling heat transfer coefficient of CO2 in a brazing type small diameter copper tube. therefore, it is necessary to develope reliable and accurate predictions determining the cooling heat transfer coefficient of CO2 in a brazing type small diameter copper tube.
참고문헌 (12)
- S. J. Kline, "Describing uncertainties in single sample experiments", Mechanical Engineering, 75(1), pp.3~12 (1953)
- K. Mori, "Cooling heat transfer characteristics of CO2 Oil mixture at supercritical pressure conditions", Proceedings of the Asian Conference on Refrigeration and Air Conditioning, pp.81~86 (2002)
- Cooling Heat Transfer of Supercritical Carbon Dioxide, The Degree of Doctor of Engineering, "C. Dang", The University of Tokyo School of Engineering Department of Mechanical Engineering, ~ (2003)
- 윤석호, "이산화탄소의 초임계 가스냉각 과정중의 열전달과 압력강하에 관한 실험적 연구", 대한설비공학회 논문집, 16(6), pp.538~545 (2004)
- B. S. Petukhov, "An investigation of heat transfer to fluids flowing in pipes under supercritical conditions", ASME International Developments in Heat Transfer, 3, pp.569~578 (1961)
- E. A. Krasonshchekov, "Local heat transfer of carbon dioxide at supercritical pressure under cooling conditions", Teplofizika Vysokikh Temperatur, 7(5), pp.922~930 (1970)
- V. L. Baskov, "Heat transfer with the turbulent flow of a liquid at supercritical pressure in tubes under cooling conditions", Teplofizika Vysokikh Temperatur, 15(1), pp.96~102 (1977)
- N. E. Petrov, "Heat transfer and resistance of carbon being cooled in the supercritical region", Thermal Engineering, 32(3), pp.131~134 (1985)
- V. Gnielinski, "New equation for heat and mass transfer in turbulent pipe and channel flow", Int. Chem. Eng., 16, pp.359~368 (1976)
- E. A. Krasonshchekov, "Experimental study of heat exchange in carbon dioxide in the supercritical range at high temperature drops", Teplofizika Vysokikh Temperatur, 4(3), pp.389~398 (1966)
- S. Pitla, "Heat transfer from supercritical carbon dioxide in tube flow: A critical review", HVAC＆ R research, 4(4), pp.281~301 (1998)
- X. Fang, "Heat transfer and pressure drop of gas coolers", ASHRAE Transaction, 107(1), pp.255~266 (2000)