Application of Low Solidity Vaned Diffusers Close Coupled to the Volute of a Turbocharger Compressor

The performance of a turbocharger compressor with a range of low solidity vaned diffusers close coupled to the collecting volute is presented. The vaned diffusers were designed with a solidity of 0.5, an inlet radius ratio of approximately 1.4, and a discharge radius ratio of 1.65 so that the flow discharged directly into the collecting volute. The experimental investigation presents the basic performance of the turbocharger together with the specific pressure recovery developed in the vaneless space, the vaned diffuser, and the collecting volute. The effect of alternative vane designs on the matching and performance of the collecting volute is discussed.