The construction of symmetric nose shapes of minimum wave drag

The problem of minimizing the wave drag of axisymmetric noses in the supersonic flow of an inviscid, non-heat-conducting perfect gas is considered. A procedure is proposed for constructing the extremal generatrix by step-by-step solution of single parameter problems using assumptions concerning the local relation between the geometric parameters and the gas-dynamic functions. A unique generatrix, from which parts are separated which form noses of arbitrary length, corresponds to the specified free-stream conditions. Comparison of the noses obtained and the noses which are optimal in the exact formulation of the problem shows that the aerodynamic characteristics are close when there is an appreciable difference between the geometric parameters. (c) 2006 Elsevier Ltd. All rights reserved.