摘要
针对全MHD(Magnetohydrodynamics)数值模拟中存在伪磁场散度的问题,发展了如下计算方法:基本格式基于八波对称形式方程组,补充相关源项以保持方程组守恒性,并采用投影方法辅助清除伪散度.投影方法中,基于有限体积方法求解三维Poisson方程.算例显示,对于光滑解析磁场,伪磁场散度得到有效清除;对于带激波高超声速MHD流动,全局投影下自由来流区域误差增大.提出一种局部投影方法,在高磁场散度区域进行投影.结果表明,最终流场收敛稳定,高磁场散度得到有效清除,而低散度区域散度不受影响.
Numerical technique is developed to clean spurious magnetic field divergence △↓ · B in full MHD (Magnetohydrodynamics) simulation. Eight-wave equations are solved in basic scheme combined with additional source term △↓ ·B to keep conservation. A projection scheme is used to clean spurious magnetic field divergence. 3D Poisson equation is solved with a finite volume method. For smooth analytical field, △↓ · B is cleaned efficiently. While for hypersonic MHD blunt flows with shock wave, △↓ ·B error increases sharply in free stream region. A local projection scheme is proposed to clean △↓ · B in relatively high divergence region. Flow field converges well and magnetic field divergence in low divergence region is not influenced.
出处
《计算物理》
EI
CSCD
北大核心
2009年第1期78-86,共9页
Chinese Journal of Computational Physics
基金
国家自然科学基金(10672179)
国防科技大学研究生创新资助项目
关键词
MHD
伪散度清除
高超声速
数值模拟
投影方法
magnetohydrodynamics
spurious magnetic field divergence cleaning
hypersonic
numerical simulation
projection scheme