Methods for the accurate computations of hypersonic flows - II. Shock-aligned grid technique

In order to eliminate or minimize the numerical error by shock waves due to grid distribution in multidimensional hypersonic flows. a new grid reconst ruction scheme, the shock-aligned grid technique (SAGT), is proposed. The e rror due to shock waves in a non-shock-aligned grid system magnifies in pro portion to the Mach number and propagates on the downstream side of the flo w field to contaminate sensitive aerodynamic coefficients or flow quantitie s. SAGT, combined with the AUSMPW+ scheme proposed in Part I of the present work, not only provides an accurate solution but also reduces the grid dep endency of a numerical scheme without a substantial increase in computation al cost. In addition, SAGT is robust and flexible enough to deal with compl ex flow problems involving shock interaction and reflection and equilibrium and nonequilibrium effects, Extensive numerical tests from a hypersonic bl unt body flow to hypersonic nonequilibrium flows validate the accuracy, eff iciency, robustness. and convergence characteristics of SAGT. (C) 2001 Else vier Science.