Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5017247 | International Journal of Refrigeration | 2017 | 42 Pages |
Abstract
In this paper, the effect of intermediate water temperature on the performance of a combined R134a and transcritical CO2 heat pump was studied theoretically and experimentally. The mathematical model was first validated using experimental data and then applied to analyze the performance of the combined system. The results show that there exists an optimal intermediate water temperature (water inlet temperature at the gas cooler) at which the combined system has the highest COP. This optimal intermediate water temperature varies with the ambient air temperature. Furthermore, the effect of intermediate water temperature on individual R134a and transcritical CO2 subsystems was investigated. The results show that both heating capacity and power consumption in the R134a subsystem increase as the intermediate water temperature increases. However, power consumption in the CO2 system drops slightly, and heating capacity reaches an optimal value as the intermediate water temperature increases from 15 to 32â°C under ambient air temperatures ranging from â20 to 7â°C.
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Physical Sciences and Engineering
Engineering
Mechanical Engineering
Authors
Yulong Song, Dongzhe Li, Feng Cao, Xiaolin Wang,