Computational Studies on Single-Wall Rotating Vaneless Diffuser of a Centrifugal Compressor Stage

This paper focuses on the computational study on the effect of single wall rotation of vaneless diffuser, namely hub side wall and shroud side wall of the vaneless diffuser. ANSYS CFX software is used to analyze the flow parameters and performance of the single wall rotating vaneless diffuser. The rotating diffusers are examined at five dimensionless mass flow rates using SVD as the base model. Using the same impeller, SVD, HRVD, SRVD, and RVD configurations are simulated and compared. Static pressure and total pressure in stationary frame are measured to understand the diffusion process in the single wall rotating vaneless diffuser. Based on the investigations, HRVD outperforms all other configurations with overall improved performance in terms of pressure rise and flow dynamics.