International Scientific Journal


The temperature lift directly influences the efficiency of the heat pump, meanwhile, the coefficient of performance and the heat sink temperature lift of heat pump systems are mutually exclusive parameters, i.e., the higher temperature lift leads to the lower coefficient of performance while the lower temperature lift leads to the higher coefficient of performance. To deal with the dilemma, a primary theoretical analysis is performed, and a case study of an inverter water source heat pump is carried out, which is operated under the conditions of compressor frequency of 15-85 Hz and heat sink flow rate of 120/160/180/200 kg/h, respectively. The relationships among the temperature lift, coefficient of performance and compressor power consumption are analyzed, The results show that the optimal temperature lift mainly depends on the inlet temperature of heat sink, and has little to do with the compressor frequency and water flow rate, which are of significance for the optimal operation of heat pump systems.
PAPER REVISED: 2013-04-20
PAPER ACCEPTED: 2013-04-25
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THERMAL SCIENCE YEAR 2013, VOLUME 17, ISSUE Issue 5, PAGES [1459 - 1465]
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