管束排列方式对矩形翅片椭圆管束性能的影响

Effect of Tube Arrangement on Performance of Rectangular Finned Elliptical Tube Bundles

摘要:

采用标准kε模型，对错排和错列两种排列方式在不同管间距下共24种结构进行了计算分析，发现错列结构的换热性能和综合性能均优于错排结构.错排结构性能跟横向管间距关系较大，而错列结构的性能对管间距并不敏感.通过对两种结构的流场、温度场特征分析，发现错列结构类似于圆管换热器中的叉排，错列结构在强化翅片换热的同时也强化了管子的换热，该结构具有较大的管束进口压力损失是造成其空气侧总压降大于错排结构的主要原因.

关键词:汽车风洞换热器; 矩形翅片椭圆管束; 流动换热性能; 错排; 错列

Abstract:

A standard kε model was used to analyze the performance of staggered row and staggered column arrangements with different tube pitches. The results show that staggered column structure is superior to staggered row arrangement in performance. As transverse tube pitch has a large impact on staggered row arrangement, staggered column structure is not sensitive to tube pitches. Staggered row arrangement is more sensitive to Reynolds number than staggered column arrangement. Based on the analysis of temperature field and flow field, it is found that the flow field of staggered row structure is similar to that of staggered round tube bundles. Besides, staggered column structure enhances heat transfer through fins as well as tubes. The big air side pressure loss of this structure is mainly caused by the large inlet loss.

Key words:automotive wind tunnel heat exchanger; rectangular finned elliptical tube bundles; flow and heat transfer performance; staggered row; staggered column