楔形板式相变单元蓄热过程的数值模拟及试验验证

Numerical simulation and experimental verification on the heat storage process of wedge plate phase change unit

为了保持板式相变单元易加工、组配灵活等特性的同时提高矩形板式单元的蓄热性能,在普通矩形储能单元的基础上调整纵向体积分布设计了一种楔形板式相变单元,通过FLUENT软件模拟2种单元所属蓄热装置在不同入口温度和不同入口流速下的蓄热过程,并通过试验研究得到了2种装置内PCM在不同工况下的温度曲线。研究表明:相对于矩形单元,楔形单元能够更好地利用相变材料的熔化特性使其率先完成相变过程,且入口流速的增大和入口温度的增加可有效地提高单元的蓄热效率,其中,入口流速为0.12 m/s、入口温度为75℃时楔形相变单元的优势体现得越发明显,在原有基础上提高了26.6%。

In order to improve the heat storage performance of the rectangular plate type unit while maintaining the characteristics of easy processing and flexible assembly of the plate phase change unit,a wedge-shaped plate phase change unit was designed by adjusting the longitudinal volume distribution on the basis of the ordinary rectangular energy storage unit.The heat storage process of the heat storage devices of the two units at different inlet temperatures and inlet flow rates was simulated using Fluent software,and the temperature curves of the PCM in the two devices under different working conditions were obtained through experimental research.The research shows that compared with the rectangular unit,the wedge-shaped unit can better utilize the melting characteristics of the phase change material to complete the phase change process first,and the increase of the inlet flow speed and the increase of the inlet temperature can effectively improve the heat storage efficiency of the unit.Among them,when the inlet flow speed is 0.12 m/s and the inlet temperature is 75℃,the advantages of the wedge-shaped phase change unit become more obvious,which was improved by 26.6%on the original basis.