Research on Circumferential Non-uniformed Characteristics of Internal Flow Field of Turbocharger Centrifugal Compressor
The stagnation effect of the turbocharger centrifugal compressor volute tongue on the airflow will result in a non-uniformed circumferential distribution of static pressure.This paper analyzes the internal asymmetric flow field of a compressor using a full-annulus,three-dimensional numerical simulation to further investigate the possibility of enhancing its aerodynamic performance.The results indicate that the distribution of static pressure inside the diffuser varies with the flow rate under different operating conditions.As the flow rate decreases,the maximum value of static pressure gradually migrates from the circumferential 90° position to the vicinity of the volute tongue.The non-uniform static pressure induced by the volute tongue will propagate counter currently to the diffuser inlet along the flow direction.In addition,the non-uniform static pressure distribution at the diffuser's inlet affects the performance of a single impeller channel;specifically,there is a"critical flow point"between the near blockage point and the flow critical point,beginning with the blade channel corresponding to the volute tongue,a single impeller channel.Along the direction of impeller rotation,the flow rate and channel loss of the blade channel decrease first and then increase,and the efficiency increases first and then decreases;between the critical point and the near-blockage point,the flow rate and channel loss of a single blade channel increase first and then decrease along the direction of impeller rotation,and the efficiency decreases first and then increases.
TurbochargerCompressorVoluteNon-uniformed flow field