壳管束相变蓄热器蓄热性能全耦合数值分析

Fully Coupled Numerical Analysis on Thermal Storage Performance of Shell and Tube Bundle Latent Heat Thermal Storage

采用数值方法分析壳管束相变蓄热器的蓄热性能.首先建立三维非稳态相变蓄热器的数值模型,然后采用块结构化网格实现网格的划分和生成,最后对相变材料的相变传热和传热流体的对流传热进行耦合分析.数值结果表明,相对于传热流体的入口流速,蓄热管束的总蓄热量受传热流体入口温度的影响更大,且潜热蓄热量仅取决于相变材料的体积.在蓄热过程中,蓄热管束的时均能效比和时均蓄热率均出现了一个峰值.随着传热流体入口流速的增加,蓄热管束的总能效比减小,总蓄热率增大;随着入口温度的增加,蓄热管束的总能效比和总蓄热率均增大.

The thermal storage performance of a shell and tube bundle latent heat thermal storage is numerically analyzed.Firstly,a three-dimensional and unsteady numerical model of a shell and tube bundle is established.The model is meshed and formed by using composite grid.Finally,the phase change heat transfer of phase-change material and the convective heat transfer of heat transfer fluid are closely coupled.The numerical results are shown as follows.The effect of inlet temperature of heat transfer fluid on total heat energy stored by shell and tube bundle is greater than that of inlet velocity.The latent heat energy stored only depends on the volume of phase change material.During the whole heat storage process,both the time-average energy efficiency ratio and the time-average heat storage rate of the shell and tube bundle have one peak.With the increase of inlet velocity of heat transfer fluid,the total energy efficiency ratio of the shell and tube bundle gradually decreases,but the total heat storage rate increases.With the increase of inlet temperature,the total energy efficiency ratio and the total heat storage rate gradually increase.