GA based optimization of the preliminary design of an extremely high pressure centrifugal compressor for a small common rail diesel engine

A method to perform the preliminary design of an impeller for an extremely high pressure ratio centrifugal compressor is introduced in this paper. The equations used are fully detailed and a design procedure is introduced. This design procedure required a GA (Genetic Algorithm) optimization to obtain an acceptable optimum result. It is demonstrated that a 8:1 compressor can be designed for a mass flow of 500 kg/h. This GA optimized initial design should be then be validated through CFD (Computational Fluid Dynamics) simulation and then tested on a test bench. However, the initial design phase is critical, since a CAD model of the impeller is needed to start the simulation process. In our case this initial phase couldn't be inspired by existing design, since none were found. Aircraft and Helicopter engines do not have the problem of turbo lag, since fan/propeller inertia eliminates this problem. On the contrary these engines necessitate of performance at altitudes (flight levels) much higher than automotive applications. Small turbochargers with high compressor ratio are not available on the market, so a special design is needed. © 2006-2015 Asian Research Publishing Network (ARPN).