基于正交试验的级联相变蓄热装置相变材料高度的优化

Height Optimization of Phase Change Material in Cascaded Latent Heat Storage Device Based on Orthogonal Test

级联潜热蓄热技术是平衡可再生能源利用与供需差距的一种有效技术,提高级联相变蓄热系统的蓄热特性具有重要意义。为研究不同相变材料高度对级联相变蓄热装置蓄热量和㶲效率的影响,采用三元二次回归正交试验结合数值模拟的方法,建立可靠且不失拟的回归方程对每层相变材料高度进行了优化。试验结果表明:每层相变材料高度对蓄热量和㶲效率会产生较明显的影响,并且每层高度的交互作用也会对蓄热量和㶲效率产生一定的影响,回归方程满足回归试验的显著性检验以及失拟性检验。通过回归方程得出在3600s时间段内蓄热量最大时的4层相变材料的最佳高度比为1:3:4:4,最大蓄热量为27.02MJ,在此时间段内㶲效率最大时的4层相变材料最佳高度比为4:3:4:1,㶲效率最大为71.26%。运用此方法可以建立任何时刻蓄热量以及㶲效率与相变材料高度之间的关系。

Cascaded latent heat storage technology is an effective technology to balance the gap between renewable energy utilization and supply and demand.It is of great significance to improve the heat storage characteristics of the cascaded latent heat storage device.In order to study the influence of different height of phase change material(PCM)on the heat storage and the exergy efficiency,a reliable regression equation with no loss of fitting was established by using the ternary quadratic orthogonal test and numerical simulation method to optimize each layer height of PCM.The test results show that each layer height of PCM has a significant effect on the heat storage and the exergy efficiency,and the interaction of each layer height also has a certain effect.The regression equation satisfies the significance test and the loss of fit test of the orthogonal test.Through the regression equation,the optimal height ratio of the four layers PCM at the maximum heat storage in 3600s is 1:3:4:4 and the maximum heat storage is 27.02MJ.The optimal height ratio of the four layers PCM at the maximum exergy efficiency is 4:3:4:1 and the maximum exergy efficiency is 71.26%.This method can be used to establish the relationship between the heat storage or exergy efficiency and the height of PCM at any time.