Boundary layer calculations for preliminary design of wings in supersonic flow

Abstract

Two classes of methods for fast calculation of three dimensional boundary layers over supersonic wings are explored and compared. These analyses are meant to be inexpensive but sufficiently accurate for advanced design studies. They are intended to be used as part of the wing aerodynamic analysis in multidisciplinary optimization of supersonic natural laminar flow aircraft. The first method is a combination of a two dimensional finite difference boundary layer calculation and a simple crossflow prediction based on wing geometry, flight condition, and analytic solutions. The second is a quasi-3D finite difference analysis taking advantage of the simplified flow conditions of swept and tapered wings. The two methods are shown to compare favorably with 3D Navier-Stokes results on representative wing planforms. Also, preliminary results of fuselage shape optimization to preserve laminar flow are presented.