家用空气源热泵蓄热式热管散热器的自然对流传热特性

Natural Convective Heat Transfer Characteristics of a Domestic Air-source Heat Pump Regenerative Heat Pipe Radiator

提出带蓄热材料的热管式自然对流散热末端新型式,在热管式末端的换热管上外加套管,管间填充蓄热材料。管内蒸气通过凝结换热,将热量传递给蓄热材料后再传递给外套管,外套管与室内空气进行自然对流传热和辐射传热,构造出新型家用空气源热泵系统。建立了带固体蓄热材料的热管式散热末端的传热模型,研究热泵系统启停过程,蓄热材料种类、厚度对温度分布随时间变化的影响;分析热泵系统的制热量、压缩机功率等宏观性能系数的变化规律。结果表明:固体蓄热材料中镁砖效果较好;热泵运行时间和蓄热材料外表面温度受蓄热体厚度影响,且存在一个临界厚度;当选取12 mm厚的镁砖蓄热材料时,带蓄热末端的家用空气源热泵运行12 min,供热时间26 min,表面温度变化在35~50℃。

A new heat pipe-type natural convective heat dissipation terminal with a thermal energy storage material is proposed.A sleeve is added to the heat exchange tube at the end of the heat pipe,and the thermal energy storage material is placed between the tubes.Through condensation heat exchange,the steam in the tube transfers heat to the thermal energy storage material and then to the outer sleeve,which features natural convective heat exchange and radiative heat exchange against indoor air,thereby constructing a new household air source heat pump system.A heat transfer model of the heat pipe heat dissipation terminal with the solid-state thermal energy storage material is established,and the start-stop process of the heat pump system and the influence of the type and thickness of the thermal energy storage material on the temperature distribution and its variation with time are studied.The variation laws of the macro-performance metrics,such as the heating capacity and compressor power of the heat pump system,are analyzed.The results show that magnesium brick as the solid-state thermal energy storage material is the best.The operating time of the heat pump and the external surface temperature of the thermal energy storage material are affected by the thickness of the thermal energy storage material,and a critical thickness exists.When a magnesium brick with a thickness of 12 mm is selected as a thermal energy storage material,the domestic air-source heat pump with the thermal energy storage terminal runs for 12 minutes,leading to 26 minutes of heating time,while the surface temperature changes within the range of 35-50℃.