矩形翅片椭圆管换热器熵产分析及结构优化

Entropy generation analysis and structure optimization of rectangular finned elliptical tube heat exchangers

中文关键词: 矩形翅片椭圆管束  排列方式  熵产分析  田口法  结构优化

英文关键词: rectangular finned elliptical tube bundles  tube arrangement  entropy production analysis  taguchi method  structural optimization.

中文摘要:

      针对矩形翅片椭圆管换热器的三种排列方式，用计算流体力学（CFD）方法，采用标准k-ε湍流模型和增强型壁面函数法得到换热器流动换热数据，在此基础上采用热力学第二定律的熵产分析法，对不同管束排列方式及各结构参数下的换热器熵产进行分析。用田口法，得到不同排列方式各结构因素对熵产的贡献率，并给出错排和错列结构的具有最小熵产的优化结构参数组合。发现错列结构不可逆损失最小，而顺排结构损失最大。横向管间距是错排结构熵产的重要影响因素，而对于错列结构，横向管间距在压力熵产中起主导作用。

英文摘要:

      The thermal-hydraulic performance of three types of arrangements of rectangular finned elliptical tube heat exchangers is simulated through standard k-ε turbulence model and enhanced wall function method of computational fluid dynamics (CFD). Then, on the basis of the second law of thermodynamics, the effects of tube arrangement and the structure parameters on entropy generation are analyzed. The contribution ratio of each structural factors to the entropy production are obtained and the optimal structural parameter combinations with minimum entropy production are given using Taguchi method. It is found that the irreversible loss sequence from smallest to largest is staggered column structure, staggered row structure and inclined row structure. The transverse tube pitch is the most important factor influencing total entropy production of the staggered row structure, while it plays a dominant role in the production of pressure entropy production of staggered column structure.