An Improved Mach-Box Approach for Supersonic Oscillatory Pressures

Abstract

An analytical refinement of the Mach-box approach has been developed which provides greatly improved supersonic oscillatory pressure distributions with almost no increase in computer time over that required by the original formulation. The refinement consists, in part, of applying physically justifiable weighting factors to the terms of the aerodynamic influence coefficient matrix. Unlike approaches that employ curve smoothing to eliminate the erratic undulations in computed pressures obtained by the basic method, the present analysis produces well-behaved pressure distributions while retaining essential flow discontinuities. Furthermore, the present method is more cost-effective than approaches relying on refinements in the aerodynamic grid to obtain comparable improvements in the calculated pressures.