改进的PPM格式及其在Riemann问题中的应用  

An improved piecewise parabolic method(PPM) scheme and its applications in Riemann problem

作　　者：陈善群[1] 廖斌[1] 

机构地区：[1]安徽工程大学建筑工程学院,芜湖241000

出　　处：《应用力学学报》2017年第3期476-482,共7页Chinese Journal of Applied Mechanics

基　　金：国家自然科学基金(51409001);安徽省自然科学基金(1508085QE100);安徽高校优秀青年人才支持计划(gxyq2017015)

摘　　要：在Collela和Skora提出的PPM格式基础之上,为消除舍入误差带来的影响,发展了一种改进的PPM格式。将改进的PPM格式结合Riemann近似解算子应用于求解Riemann问题。选取双膨胀波和Rayleigh-Taylor不稳定性问题作为算例进行了数值验证,并将改进的PPM格式与原始PPM格式的求解结果进行了对比分析。结果表明:改进的PPM格式相较于原始PPM格式的求解精度有了明显提升;计算结果更加合理,气泡发展曲线与解析解更为接近。Based on the piecewise parabolic method(PPM)scheme presented by Collela P and Skora M D,an improved PPM scheme is developed by eliminating sensitivity to roundoff.Coupled with an approximate Riemann solver,the improved PPM scheme is used to solve the Riemann problem.Double expansion wave and Rayleigh-Taylor instability problem are chosen as numerical examples to test and verify the improved scheme.A comparative analysis between the improved and the traditional PPMs is also carried out.It is found that the improved PPM scheme is a relatively more precise method than the traditional PPM scheme.

关 键 词：改进的PPM格式 原始PPM格式 RIEMANN问题 Riemann近似解算子 

分 类 号：O354[理学—流体力学]