As internal-combustion engine power density has increased

turbocharger with high pressure ratio is required.With a Fully three-dimension CFD technology

a transonic centrifugal compressor with pressure ratio 4.0 for vehicle was designed and also applied to micro gas turbine.The design methods and principle of transonic centrifugal compressor were analyzed.The engine-matching test shows that

the performance of the engine improved significantly with the new designed compressor as compared to the prototype compressor.The engine fuel consumption was reduced by 4.1 g/kW·h and the inlet temperature of turbine was decreased by 35 K.