Ideal magnetohydrodynamic flow around a blunt body under anisotropic pressure

The plasma flow past a blunt obstacle in an ideal magnetohydrodynamic (MHD) model is studied, taking into account the tensorial nature of the plasma p ressure. Three different closure relations are explored and compared with o ne another. The first one is the adiabatic model proposed by Chew, Goldberg er, and Low. The second closure is based on the mirror instability criterio n, while the third depends on an empirical closure equation obtained from o bservations of solar wind flow past the Earth's magnetosphere. The latter i s related with the criterion of the anisotropic ion cyclotron instability. In the presented model, the total pressure, defined as the sum of magnetic pressure and perpendicular plasma pressure, is assumed to be a known functi on of Cartesian coordinates. The calculation is based on the Newtonian appr oximation for the total pressure along the obstacle and on a quadratic beha vior with distance from the obstacle along the normal direction. Profiles o f magnetic field strength and plasma parameters are presented along the sta gnation stream line between the shock and obstacle of an ideal plasma flow with anisotropy in thermal pressure and temperature. (C) 2000 American Inst itute of Physics. [S1070- 664X(00)04407-4].