相变蓄热器多温位释热特性模拟研究

针对翅片管式相变蓄热器多温位释热过程进行数值模拟,分析其多温位相变传热过程的放热特性。结果表明,蓄热器低温级相变材料温度的变化速率高于高温级相变材料温度的变化速率,这是因为蓄热器低温级制冷剂流量高于高温级制冷剂流量,且低温级制冷剂出口温度与相变材料的温差高于高温级。采用热焓法对单管蓄热器模型在第一类边界条件下的融化和凝固过程进行数值模拟,并与实验测得的数据进行对比,模拟分析蓄热器高、低温级液相率及温度变化情况,综合分析相变传热过程的蓄放热特性,为进一步优化蓄能除霜过程高、低温级能量分配提供理论基础。

Simulation study on multi-temperature heat release characteristics of a phase change accumulator

According to the numerical simulation of the multi-temperature heat release process of a finned tube solid-liquid phase change regenerator, the heat release characteristics of the multi-temperature phase change heat transfer process were analyzed. The results show that the temperature change rate of low-temperature phase-change material of the regenerator is higher than that of high-temperature phase-change material. This is because the flow rate of low-temperature refrigerant of the regenerator is higher than that of high-temperature refrigerant, and for low-temperature refrigeration, the temperature difference between the outlet temperature of the agent and phase change material is higher than that for high temperature refrigeration. The enthalpy method was used to numerically simulate the melting and solidification process of the single-tube regenerator model with the first type of boundary conditions. The high- and low-temperature liquid phase ratios and the temperature changes of the regenerator were simulated and analyzed, and compared with the experimentally measured data. A comprehensive analysis on the heat storage and discharge characteristics of the phase change heat transfer process was arride out, which can further improve the high and low temperature energy distribution of the energy storage defrosting process.