EXPERIMENTAL INVESTIGATION OF LOCAL HEAT TRANSFER COEFFICIENT FOR REFRIGERANT FLOW BOILING IN MICROCHANNEL COLD PLATE EVAPORATORS
The local two-phase heat transfer coefficient is the key parameter needed for accurate prediction of the heat transfer rate in microchannel cold plate evaporators used in electronics cooling systems. Many of the recent studies of the heat transfer coefficients in microchannel heat exchangers for electronics cooling were developed for water as the heat transfer fluid and in the subcooled or low vapor-quality region. In contrast, the present study focuses on the investigation of the local flow boiling heat transfer coefficient at different vapor qualities (up to saturated vapor) of the refrigerant R-134a. An experimental setup was designed and built to measure the local heat transfer coefficient and to obtain a better understanding of the underlying physics. The evaporator considered contains 17 parallel microchannels which are each 762 μm wide and 1905 μm deep. The change in vapor quality across the test section was fixed to 20％ in any given experiment. Measurements were conducted for several inlet vapor qualities ranging from subcooled liquid to a vapor quality of 80％ at saturation temperatures between 10℃ and 30℃ and refrigerant mass flow rates from 0.5 g/s to 2 g/s.
STEFAN S.BERTSCH ECKHARD A.GROLL SURESH V.GARIMELLA
Purdue University, School of Mechanical Engineering Ray W. Herrick Laboratories, West Lafayette, Indiana 47907, USA
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）