求解超声速无粘绕流的杂交型有限元格式

A Hybrid Finite Element Scheme for Inviscid Supersonic Flows

Department of Mechanics and Engineering Science, Peking University, Beijing 100871, P. R China

摘要: 本文从一维双曲型标量方程出发,以一个普通二阶有限元格式及由其单边对角化导出的一阶单调型格式为基础,构造出一种具有单调性的杂交型有限元格式.为了向二维Euler方程组情形推广,所采用的开关函数是基于流场梯度的局部函数,并专门考虑了相邻单元的影响.二维情形的算例表明新格式可以明显抑制激波附近的振荡.
- 有限元 /
- 杂交格式 /
- 激波
Abstract: A hybrid monotonous finite element algorithm is developed in the present paper,based on a second-order-accurate finite elment scheme and a first-order-accurate monotonous one derived from the former by a unilateral lumping procedure in onedimensional case. The switch functions for the two dimensional Euler equation systemare constructed locally, based on the gradient of the flow field, with specialcon sideration on the information from neighboring elements.Examples show that the new scheme can eliminate oscillations near strong shocks obviously.
- finite element /
- hybrid scheme /
- shocks

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