带相变储能的太阳能热水系统分析

提出相变材料(PCM)+水的太阳能联合储能方案,将其应用于24 h供热水的传统太阳能加电辅热热水系统中,建立PCM+水联合储能的数学模型。将该系统应用于昆明地区的情况进行全年模拟分析,对比有无PCM时储热水箱中水温的变化、热损失及电辅热耗电量。结果表明PCM联合储能的热水系统,储热水箱中水温波动小;即加入PCM联合储能对水箱中水温有"削峰填谷"的作用,热损失和电辅热耗电量均减小,全年节电率达17.7%。分析了相变温度与PCM体积比(PCM体积与水体积之比)对水箱储能性能的影响,给出了水箱储热性能随相变温度和相PCM体积比变化的规律及其选取范围。

Study on the application of phase change energy storage in solar water heater system

The solar energy storage plan combining the phase change materials(PCM) with water is proposed. The plan is applied in conventional solar energy system associated with electric auxiliary heat, which offers heat water in 24 hours. The mathematical model is built. An annual simulation is made to compare the performance of the system with PCM and without PCM in Kunming. The results show that the water temperature fluctuation is smaller in the system with PCM, which means that the PCM causes an effect as "chipping peak off and filling valley up". This effect on water temperature is beneficial for the system, since the heat loss and the electric auxiliary heat consumption are reduced, resulting in the electricity saving rate up to 17.7%. The influence that PCM melting temperature and volume fraction have on the performance of the energy storage system is analyzed and the selection range is provided.