Heat Transfer Characteristics of Cold Water Phase-Change Heat Exchangers under Active Icing Conditions

Abstract

Under active icing conditions, the heat transfer performance of the CPHE has a significant impact on the system’s efficiency and energy consumption. Using the enthalpy-porosity method for describing the solidification process of liquids, the simulation and analysis of the effects of different parameter changes on the CPHE heat transfer performance were conducted to clarify the effects of the changes in the intermediary side inlet water temperature, intermediate water flow rate, and cold water flow rate on the heat transfer process in the CPHE. According to our results, changing the intermediary inlet water temperature has a greater impact on the heat transfer process in the cold-water phase-change heat exchangers. For every decrease of 0.5 °C in the intermediary side inlet water temperature, the average heat transfer coefficient increases by approximately 50 W/m2-K. Changes in the intermediary water flow rate affect the cold water phase-change heat exchanger’s heat transfer process. By increasing the intermediary water flow rate, the average heat transfer coefficient of a cold water phase-change heat exchanger can be improved, but the growth decreases, and the maximum flow rate of the intermediary water should not exceed 0.5 m per second. A change in the cold water flow rate in the cold water phase-change heat exchanger’s heat transfer process has a small impact on the cold water flow rate, increasing by 0.02 m/s each, with the average heat transfer coefficient increasing by 20 W/m2-K.

Heating Performance and Economic Analysis of Solar-Assisted Cold-Water Phase-Change-Energy Heat Pump System in Series and Parallel Connections

“…Increasing the intermediate water flow rate can improve the average heat transfer coefficient of the PCM. However, an increase in the average heat transfer coefficient of the PCM slows down with an increase in the intermediate water flow rate [7]. Compared to conventional heating and cooling methods, WPCHPs have the advantages of low energy consumption, high energy efficiency, and significant economic benefits.…”