基于特征分裂改进的WENO格式与Roe格式对比研究  

Comparative study about improved WENO scheme based on characteristics splitting and Roe scheme

作　　者：石磊[1] 闫溟[1] 龚安龙[1] 周伟江[1] 

机构地区：[1]中国航天空气动力技术研究院,北京100074

出　　处：《计算力学学报》2014年第6期805-810,共6页Chinese Journal of Computational Mechanics

摘　　要：双曲性守恒方程组采用高阶、高分辨率的WENO格式时有两类分裂方法,即逐点分裂和特征分裂。本文基于后者,对特征分裂重构时强间断和接触间断位置出现的振荡情况进行研究,对重构变量加以改进,发现改进后的WENO格式克服了间断处的振荡,然后以LU-SGS为子迭代的双时间步法求解Euler方程,选用一维Sod、二维前台阶和双马赫反射算例,并与Roe格式计算结果进行对比,发现WENO格式分辨率更高,耗散更小。Unphysical oscillations at shock waves and contact discontinuities are discussed in Lax’s prob-lem using WENO scheme based on characteristics splitting method.Then we improved construction variables to avoid this phenomenon.Several typical examples including Sod’s problem,forward facing step and double mach reflection are calculated according unsteady Euler equation with improved WENO scheme and LU-SGS implicit time-marching method.Compared with Roe scheme,the improved WENO scheme shows higher resolution and lower diffusion.

关 键 词：高阶 高分辨率 WENO格式 非定常 Roe格式 

分 类 号：O357.1[理学—流体力学]