相变贮热管管内强化传热的数值研究

NUMERICAL INVESTIGATION ON ENHANCED HEAT TRANSFER IN SHELL-AND-TUBE PHASE CHANGE HEAT EXCHANGER

以管壳式相变换热器为例,研究了肋片对增强贮热管管内传热的影响。建立了内部设置肋片的贮热管放热过程的数理模型,分析比较了不同的肋片参数,如肋片布置密度、长度及厚度等因素对贮热管放热效果的影响,并通过瞬态传热过程的计算,确定了与多种肋片布置方式所对应的相变贮热管的有效导热系数。

In a shell-and-tube phase change heat exchanger, the thermal resistance of the phase change material inside the phase change heat storage tube is much larger than that between the tube and the water flow in the shell-side. To enhance the heat transfer inisde the tube, the arrangement of metal fins inside the tube was considered, and a theoretical model on the heat release process of the heat storage tube with fins was set up, and the influences of different parameters of the fins on the heat transfer inside the tube under given outside convection conditions were analyzed. Thorough the comparison of the results of the tube with inner fins and those of the tube without fins but with hypothetical thermal conductivities, the feefctive thermal conductivity of the tube with fins was determined.