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The unsteady, inviscid flowfield that results when a supersonic vehicle strikes a planar oblique shock wave, though difficult to simulate experimentally, is quite easy to model and compute numerically. The complicated flowfield, which contains multiple shock wave interactions, is determined using a second-order, shock-capturing, finite-difference approach which solves the time-dependent Euler equations under a self-similar transformation. A series of numerical results for a simple two-dimensional wedge is presented which describes the entire disturbed region, including the wave structure, and shows good agreement with the available two-and three-dimensional experimental data.

The unsteady, three-dimensional flowfield resulting from the interaction of a plane shock with a cone-shaped vehicle traveling supersonically is determined using a second-order, shock-capturing, finite-difference approach. The time-dependent, inviscid gas dynamic equations are transformed to include the self-similar property of the flow, to align various coordinate surfaces with known shock waves, and to cluster points in the vicinity of the intersection of the transmitted incident shock and the surface of the vehicle. The governing partial differential equations in conservation-law form are then solved iteratively using MacCormack's algorithm. The computer simulation of this problem, compared with its experimental counterpart, is relatively easy to model and results in a complete description of the flowfield including the peak surface pressure. The numerical solution, with its complicated wave structure, compares favorably with the available schlieren photographs, and the predicted peak surface pressures obtained are shown to agree better with the experimental data than existing approximate theories.

The wall-pressure field in a turbulent channel flow has been obtained from a numerical solution of the Navier–Stokes equations. The root mean square pressure normalized with respect to the wall shear stress, as well as the convection velocity of the field, are in good agreement with experiment. Certain limitations of the calculation, associated with its finite spatial resolution, are discussed.