驻波场中圆柱形换热管外声流特性的数值研究

基于非线性Navier-Stokes方程推导了一般性的声流控制方程,并利用有限元软件COMSOL对平面驻波声场中单根圆柱形换热管和双圆柱形换热管外包含二阶流场信息的Navier-Stokes方程进行全域求解,得到了一阶和二阶流场信息.研究了雷诺数Re和斯特劳哈尔数Sr对换热管外声流结构的影响规律.研究发现:随Re和Sr...

Numerical study on the characteristics of the acoustic streaming outside a cylindrical heat exchanger in a standing wave field

Based on the nonlinear Navier-Stokes equation,the general acoustic streaming control equation was derived.The N-S equations containing the second order flow field information of a single cylindrical heat exchange tube and a double cylindrical heat exchange tube in the plane standing wave sound field were solved in whole domain by using the finite element software COMSOL.The first and second order flow field information were obtained.The effects of Reynolds number Re and Strouhal number Sr on the structure of acoustic streaming outside the heat exchange tube were studied.It is found that with the increase of Re and Sr,the vortex area in the boundary layer of the heat exchanger tube decreases until it disappears,while the vortex area outside the boundary layer increases gradually.The number of vortices outside the single heat exchanger tube is reduced from 8 to 4,and the number of vortices outside the double heat exchanger tube is reduced from 12 to 8.In addition,the vortex structures inside and outside the boundary layer are all reverse rotation.The flow field outside the boundary layer goes far away from the heat exchange tube along the direction of oscillation,and flows toward the heat exchange tube in the vertical direction.