流过管束的流动换热与结构的综合性能评价

对于流过管束的流动换热过程以给定换热结构使换热量最大为条件导出经济结构尺寸与换热参数间的关系式，并借助于换热准则关系得出其与流动参数间的关系式；进而以过程中相对炯损失率最小为条件导出该流动换热过程最佳流动参数的表达式．联立上述两个关系式就可得出使过程的结构尺寸、流动特征与换热性能间综合优化的最佳管排与给定热流和管径间的关系式，以此作为性能分析与评估的判据，这里以流过叉排管束为例进行综合性能的分析与评价，

A comprehensive performance evaluation of fluid flow heat transfer through tube banks

The relationship of economical structure size with th e convective heat transfer parameters for fluid flow across the tubes was derived under the condition of the maximum convective heat flow for a given heat exchang e area, and the optimal flow parameter (Re) relative to structure size, heat flux and physical properties was determined by analyzing the exergy (available exergy) loss rate of the convective process. The synthetic performance optimizat ion relationship for the tube structure, fluid flow and heat transfer can be obt ained by connecting the above-mentioned two relationships. It was used as a cri terion for the performance evaluation. The comprehensive optimization for the fl ow and heat transfer process can be completed in the design stage of thermal dev ice to avoid hysteretic evaluation for the structure of practical heat devices a nd its performances.