Aerodynamic Analyses of Airfoil Configurations of Biplane Type Supersonic Transport

Abstract

In supersonic flight, airplanes cause strong sonic booms and wave drags accompanied by shock waves. It is necessary that airplanes have low noises and high efficiencies to realize next generation supersonic transports. It has high possibility that these two objectives can be achieved using a concept of Busemann Biplane. Motivated by the concept, aerodynamic design of biplane configuration in supersonic flight is discussed based on Computational Fluid Dynamics (CFD). In order to focus on the shock wave characteristics around a biplane configuration, inviscid flow (Euler) analyses are performed, which is particularly suitable for wave drag analyses. The purpose of this paper is to examine characteristics of Busemann Biplane and to demonstrate new biplane configurations which have better aerodynamic performance based on Busemann Biplane. The aerodynamic design is performed using an iterative inverse design method that has been recently implemented. This is the method that geometries are detemined by given target pressure distributions. We expect that the inverse design method may prove to be a highly appropriate tool in finding a biplane configuration to achieve minimum wave drag under a given lift condition. By the use of the inverse design method an improved airfoil shape for the biplane has been obtained