Aerodynamic Optimization of the Aeropropulsive System of a Ramjet Powered Missile

The flight performance of a ramjet-powered missile is improved through the use of an automated optimization loop relying on CFD tools. A generic supersonic air-breathing missile is first described and its performance is assessed for a representative mission. A simplified aerodynamic model obtained by Reynolds-Averaged Navier-Stokes computations is used to solve flight equilibrium. The optimization loop links together a genetic algorithm with an aerodynamic software computing the aerodynamic balance of the missile. Several optimizations are performed using different global stochastic algorithms such as Simplex, Evolutionary Strategies or Genetic Algorithms. The first ones are mono-objective: for each point of the mission (acceleration, cruise and maneuver), the best inlet shape has to be found. Then multiobjective optimizations are performed in order to find the Pareto Front, i.e., the best set of shapes satisfying the whole mission.