太阳能-空气源热泵供暖用低温相变蓄热末端装置蓄能单元的蓄放热特性

Thermal characteristics of energy storage unit of low temperature phase change heat storage terminal device for solar-air source heat pump heating

采用石蜡/膨胀石墨为相变材料,创造性地设计出一种适用于空气源热泵或太阳能等可再生能源供暖系统的低温相变蓄热末端装置。制作一个相变温度约43℃的螺旋管式相变蓄热单元并建立数值模型,结合实验测试热媒温度为50℃时的蓄放热特性,以验证模型的准确性。模拟分析热源供水温度、流量、传热面积、放热表面风速等因素对蓄热单元蓄放热性能的影响。结果表明:传热面积和热媒温度对蓄热单元的蓄热性能影响显著,热媒流速对蓄热效果的影响不明显,放热表面风速对蓄能单元放热速率影响不显著,研究成果可为优化该相变蓄热末端装置提供依据。

Using paraffin/expanded graphite as phase change materials,this paper creatively designed a suitable for air source heat pump or renewable energy sources such as solar energy heating system of low temperature phase change heat storage unit,and produced a phase change temperature 43℃spiral pipe type phase change heat storage unit and the numerical model was established.Through test water at 50℃temperature heat storage properties,the accuracy of the model is verified.The effects of water supply temperature,flow rate,heat transfer area and wind speed on heat storage and release performance of heat storage unit were simulated and analyzed.The results show that the heat transfer area and heat source water temperature have significant effects on the heat storage performance of the unit,the water supply flow has little effect on the heat storage effect,and the wind speed of the heat release surface has little effect on the heat release rate of the unit.The research results can provide a basis for optimizing the phase change heat storage terminal device.