采用自然对流换热的空气源热泵热水器实验研究

摘要

An integrated air source heat pump water heater with natural convection heat transfer evaporator and condenser was designed and fabricated. Experimental studies were carried out to get the variation of water heater performance with ambient temperature, the optimal working fluid charge and capillary length. The influence of the operation of heat pump on the indoor temperature was analyzed. The experimental results showed that the coefficient of performance (COP) of the heat pump water heater system is 2.83 under the standard test conditions. At an ambient temperature of 10 oC, it took about 450 min to raise the water temperature in the 150 L water tank from 10 oC to 55 oC and about 210 min from 30 oC to 55 oC. Frost was observed in the experiments and it melted as the evaporation temperature increased. In addition, obvious pressure loss and water condensation phenomena in the evaporator were analyzed. This study offers the theoretical and experimental reference for further application of this type heat pump water heater.%本文设计加工了蒸发器与冷凝器均采用自然对流换热的一体式空气源热泵热水器，并通过实验获得了热水器性能随环境温度的变化关系、优化的工质充灌量和毛细管长度，评价了热泵运行对室内温度的影响。研究表明，标准工况下该热泵热水器的能效比达到2.83；环境温度为10℃时，150 L水箱中的水从10℃升到55℃，需要约450 min；而环境温度为30℃时需要约210 min。观察了蒸发器结霜现象，随着热泵运行蒸发温度提升，霜会自行化解；对丝管式蒸发器存在的较明显的压力损失和冷凝水现象进行了分析应对。研究结果为此类热泵热水器的应用提供了一定的理论分析与实验依据。