应用科学学报 ›› 1997, Vol. 15 ›› Issue (1): 96-100.

• 论文 • 上一篇    下一篇

在控制方程为双曲型的问题中SUPG方法与Galerkin方法的比较

王立刚, 华律   

  1. 浙江大学
  • 收稿日期:1994-10-17 修回日期:1995-03-15 出版日期:1997-03-31 发布日期:1997-03-31
  • 作者简介:王立刚,浙江大学力学系,杭州 310027
  • 基金资助:
    国家自然科学基金,中科院化学所高分子物理实验室开放基金

THE ADVANTAGE OF STREAMLINE-UPWIND PETROV-GALERKIN FINITE ELEMENT METHOD FOR HYPERBOLIC SYSTEMS

WANG LIGANG, HUA LU   

  1. Zhejiang University, Hangzhou, 310027
  • Received:1994-10-17 Revised:1995-03-15 Online:1997-03-31 Published:1997-03-31

摘要: 常规Galerkin方法只适用于离散椭圆型方程,而在许多流动和传热问题中控制方程的类型会发生转变,由于对流项占优而成为双曲型,这时Galerkin方法的结果将产生失真振荡。采用流线迎风Petrov-Galerkin方法可以提前抑制与流动方向相垂直的扩散,从而大大提高了求解的精度。文中计算了两个问题:Oldroyd-B流体绕圆管内一球的流动和非等温搅拌流动。结果证实了当Wi数或Pe数较大时,Galerki方法得到失真振荡的解,而nSUPG方法可以得到较好的结果。

关键词: 流线迎风Petrov-Galerkin, Galerkm方法, 双曲型, 有限元

Abstract: The conventional Glalerkin finite element metbod is only applicable to discretizing elliptic equations. In many flow or heat-transfer problems, the governing equations may change type; they become hyperbolic because convection is dominating. The solutions are often corrupted by node-to-node oscillations or ‘wiggles’ the Streamline-Upwind Petrov-Galerkin finite element method can inbibit the crosswind. diffusion and improve the computational accuracy. Two aumerical exarnples are given:the flow of Oldroyd-B fluid around a sphere in a tube and the nonisothermal agitating flow When the Weissenberg number or the Peclet umber is high, the Ga]erlkin method produces,wiggles' while SUPG method yields good results.

Key words: BUPG method, Galerkin method, finite element, hyperbolic