微胶囊化相变悬浮液层流传热强化的参数分析

通过对微胶囊相变悬浮液管内层流恒热流对流换热的数学建模和模拟计算,获得在恒热流加热边界条件下,不同参数匹配时相变糊状区的确切范围以及固液相变两条相界面的数值结果。利用该模型对影响悬浮型固液两相流传热特性的诸多参数进行了比较细致的定量分析,这些参数包括固相体积浓度、斯蒂芬(Ste)数、粒径比、无量纲相变温度区间宽度以及无量纲过冷度等。分析和模拟计算的结果显示微胶囊浓度和斯蒂芬数对管内层流传热具有最重要的影响。

PARAMETERS ANALYSES ON HEAT TRANSFER ENHANCEMENT FOR MICROENCAPSULATED PHASE CHANGE SUSPENSION IN LAMINAR TUBE FLOW

A mathematical model was established and a simulation computation was carried out for laminar convective heat transfer of microencapsulated phase-change suspension in a circular tube, and the numerical results for mushy region and solid-liquid interfaces were obtained under constant heat flux condition. Using this model, detailed analyses were performed for some parameters that influence heat transfer characteristics of the microencapsulated suspension flow. These parameters include the volumetric concentration, the Stephen number, ratio of the particle and tube radii, the dimensionless width of phase-change temperature, and the dimensionless super-cooling. It was concluded that the volumetric concentration and the Stephen number have the most important influence on the heat transfer characters of the microencapsulated phase change suspension in laminar tube flow.