计算物理 ›› 1986, Vol. 3 ›› Issue (2): 155-160.

• 论文 • 上一篇    下一篇

低Re数非线性绕流问题的一种算法

张峻岫, 雷旭明   

  1. 北京大学
  • 收稿日期:1985-07-23 出版日期:1986-06-25 发布日期:1986-06-25

A COMPUTATION OF LOW REYNOLDS NUMBER NON-LINEAR FLOW PAST A BODY

Zhang Jun-xiu, Lei Xu-ming   

  1. Peking University
  • Received:1985-07-23 Online:1986-06-25 Published:1986-06-25

摘要: 本文对低Re数非线性绕流问題提出了一种算法。做法是以Oseen线化方程为基础通过迭代修正来考虑非线性的惯性项的影响,即先将Navier-Stokes方程写作Oseen方程外加一"强迫函数"项的形式,然后用基本解‘Oseenlet’的积分形式给出其解式,它是一个含物面积分和流动空间积分的非线性积分微分方程。设沿边界上的‘Oseenlet’分布强度为待求量,由边条件加以确定。空间体积分由于有赖于流场,而它在求出解前是未知的,故采用迭代修正的做法进行处理。迭代过程从线性流场开始进行,直到算出达到规定精度要求的收敛解为止。作为算例,对圆柱绕流问題进行了计算,给出了圆柱阻力随Re数的变化规律,并同实验及有关计算资料做了比较。结果表明,本文方法是令人满意的。

Abstract: This paper presents a method of solving low Reynolds number non-linear flow past a body. To be based on Oseen's equation, the effect of non-linear terms is considered by successive iteration. First, we write Navier-Stokes equation as Oseen's equation,with a forcing function (i, e, non-linear terms);then,this equation solution is given by a integral form of the ‘Oseenlet’. It is a non-linear integral-differential equation which involves a body surface integral and a flow space integral. Let distributive intensity of the ‘Oseenlet’ on the surface be unknown. They are decided by the boundary condition. Since the Space integral depends on the flow field which is not known prior to solution, an iterative scheme is used. The iterative process continues until a convergent solution is complete.This method is used to evaluate the drag acting on a single cylinder in uniform flow until Reynolds number Re=10. The obtaining results is-compared with the experimental data and the related results. It indicates that the present method is satisfactory.