EVAPORATING HEAT TRANSFER AND PRESSURE DROP OF CO2 IN A MULTI-CHANNEL MICRO-TUBE
In this paper, the evaporating heat transfer and pressure drop characteristics of carbon dioxide has been experimentally investigated in a multi-channel micro-tube. The aluminum tube, which is directly heated by the electricity, has 6 channels with a diameter of 0.8mm and a length of 1.1m. The experimental apparatus consists of the test-section, heat exchanger, accumulator, gear pump, mass flowmeter, pre-heater. The experiments were carried out in various operating conditions. The heat fluxes were in the range of 0-18 kW/m2; the mass fluxes were 400 – 1000 kg/m2s; and the evaporation temperature were 0-10℃. It was found that the HTC dropped rapidly if the quality was higher than 0.5 or so. The effect of the mass flux on the HTC was not clear. However, the HTC was increased with the increasing heat flux. It was also slightly increased at higher evaporating temperature. The pressure drops at the same mass flow rate were found to increase with the increasing heat flux and decreasing evaporation temperature.
Siyoung JEONG Dongho PARK
Dept. of Mechanical Engineering, Sogang Univ., CPO Box 1142, Seoul, KOREA Graduate School, Dept. of Mechanical Engineering, Sogang Univ., CPO Box 1142, Seoul, KOREA
国际会议
The 22nd International Congress of Refrigeration(第22届国际制冷大会)
北京
英文
2007-08-21（万方平台首次上网日期，不代表论文的发表时间）