The database of the centrifugal compressor impeller performance was given by Concept NREC software. The relationship of the impeller's main design parameters and performance was established by BP (back propagation) artificial neural network. Then the optimal array of main design parameters was acquired by the multi-objective genetic algorithm. This design method was used to satisfy Krain impeller's performance objective; the optimized impeller's efficiency and pressure ratio increased by 1.4% and 10.9%

respectively. Through discussion of artificial neural network model's reliability

multi-objective optimization model's principal component analysis and the impellers' CFD numerical simulation verification

the validity of objective functions and Pareto optimal solutions was proved

the effectiveness of the present centrifugal compressor design method was well confirmed.