Flow Computations in Inlets at Incidence Using a Shock Fitting Bicharacteristic Method

Abstract

An analysis is presented for calculating the flowfield in supersonic mixed-compression aircraft inlets operating at angle of attack. The flowfield is computed by a steady three-dimensional bicharacteristic method. The bow shock wave and the reflected internal shock wave system are computed by a three-dimensional, discrete shock wave fitting procedure. Viscous and thermal diffusion may be included as source terms in the bicharacteristic method. A production type of computer program capable of determining the flowfield in a variety of axisymmetric mixed-compression supersonic inlets is available. The results of the present analysis agree well with those produced by the two-dimensional method of characteristics when axisymmetric flowfields are computed. For three-dimensional flowfields, the results of the present analysis agree well with experimental data except in regions of high viscous interaction and boundary-layer removal. The present analysis does not compute the boundary layer, nor does it account for boundary-layer bleed.

Compressible High-Speed Gas Flow

“…This presents very large computational difficulties and it can be said that to date such trials have only been limited to one-dimensional problems and have not really been used to any extent in two or three dimensions. For this reason we shall not discuss such shock fitting methods further [52,53].…”