环形流道内扰流柱参数优化的模拟分析

Simulation Analysis for the Parameter Optimization of Double Pipes with Pins

套管结构可以通过多种被动式方法提高其传热效率。通过正交试验和数值模拟的方法,以努塞尔数Nu、阻力系数f和综合评价指标PEC作为评价指标,制定了6因素3水平的正交试验,对设置在套管环形流道内不同参数的扰流柱进行了数值模拟。对正交试验结果进行极差分析,得到各因素对Nu、f和PEC的影响趋势,并最终以PEC确定了扰流柱的最优参数组合(PEC=1.973)。基于场协同理论进行分析,具有扭转角的椭圆形扰流柱大幅提高了环形流道内流体的径向速度,约可达到轴向速度的4%,显著提升了换热壁面处的温度场和速度场的协同效果,起到了强化传热的作用。

The heat transfer efficiency of double pipes can be enhanced by passive methods.In this paper,through making use of the orthogonal test and numerical simulation,having Nusselt Nu,resistance coefficient f,comprehensive evaluation index PEC taken as the appraisal indexes to design a 6-factor 3-level orthogonal test to simulate the double-pipe pins with different parameters set in the double-pipe flow channel.Through the range analysis of orthogonal test results,the influence trend of each factor on Nu,f and PEC were obtained and the double-pipe pins’optimal parameter combination was finally determined by PEC(PEC=1.973).Based on the field synergy theory,the elliptic double-pipe pins with torsion angle greatly improves radial velocity of the fluid in the double-pipe flow channel,which can reach about 4%of the axial velocity,and significantly improves the synergy effect of both the temperature field and the velocity field at the heat transfer wall,which plays a role in enhancing the heat transfer.