The application of rapid aerodynamic prediction techniques to supersonic aircraft

Abstract

When considering new designs of supersonic aircraft, the ability to assess many different configurations with relative accuracy is of the utmost importance. Since the 1950s, simple component flows for axisymmetric bodies, wings and other lifting surfaces have been widely used in a technique known as the component build-up approach. Each component is separately modelled using methods designed for specific scenarios where their accuracy is high. The effect of each component on the others is then calculated and they are summed. This gives, typically, lift and pitching moment. This technique has remained relatively unchanged and, with the advent of higher order methods, the lower order methods have often been overlooked. This study uses the component build-up approach to predict lift and presents a new technique for drag acting upon a full aircraft. The aim of this paper is to demonstrate the accuracy and speed of these methods. The X-15 research aircraft was chosen as a test case due to its wealth of supersonic full-scale data. The presented methods predict lift to within 3.7% and drag within 6.3% of experimental data for a range of Mach numbers from 1.9 to 6. When comparing this low fidelity method with high fidelity steady Reynolds-averaged Navier-Stokes simulations, both computational data sets match well.