不同截面柱体绕流及换热特性的数值研究

Numerical Study of Winding and Heat Transfer Characteristics of Columns of Different Cross Sections

为了研究不同截面柱体绕流及换热特性,使用Fluent软件数值模拟了圆柱、方柱、三棱柱三种柱体绕流和换热问题,得到了不同截面柱体的绕流及换热规律。结果表明:方柱和三棱柱的平均阻力系数相近,且均大于圆柱平均阻力系数;方柱的升力系数幅值最大,其次为圆柱,三棱柱最小。方柱和三棱柱的漩涡脱落频率相近,且均小于圆柱的漩涡脱落频率。增大雷诺数可以提高柱体表面换热系数,三种柱体表面换热能力为:三棱柱>方柱>圆柱。

In order to study the flow and heat transfer characteristics of columns with different cross-sections,three kinds of columns,namely,cylindrical,square and triangular,were numerically simulated using Fluent software and the flow and heat transfer patterns of columns with different cross-sections were obtained.The results show that:the average drag coefficients of square and triangular prisms are similar and both are greater than the average drag coefficient of the cylinders;the amplitude of lift coefficient is maximum for square columns,followed by cylinders and minimum for triangular prisms.The frequency of vortex shedding is similar for square and triangular prisms and both are less than the frequency of vortex shedding for cylinders.Increasing the Reynolds number can improve the surface heat transfer coefficient of the column,and the three kinds of column surface heat transfer capacity are:triangular prism>square column>cylindrical.