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Study on noise characteristics of two-stage centrifugal air compressor for fuel cell

With the development of fuel cell, how to reduce the noise of fuel cell system has become an important problem. The main components of the noise include the aerodynamic noise of the centrifugal compressor and the electromagnetic noise of the motor driving the compressor. In order to solve the problem, the flow-acoustic field coupling method is used to simulate the aerodynamic noise caused by centrifugal compressor, and the electromagnetic-acoustic field coupling method is used to simulate the electromagnetic noise caused by motor. By changing the tip clearance of the centrifuge, the changes of performance such as volume efficiency, adiabatic efficiency and pressure pulsation of the centrifugal compressor are compared and analyzed. By changing the air gap and coils height of the motor, the variation of electromagnetic force and electromagnetic noise is compared and analyzed. In conclusion, noise can be reduced by setting appropriate centrifuge clearance and motor air gap and coils lengths.