Numerical simulation of 3-D steady swirling flow inside a centrifugal volute

A numerical simulation is performed on a centrifugal blower to investigate the interaction between impeller and volute for volute's distorted inlet flow, which is more intensive at off-design conditions. Three different vortices are captured at prescribed circumferential cross sections along the volute flow path. Each vortex has its own development, which influences the loss variation in the volute. In comparison with the swirling flow structure simulated by an uniform inlet flow, the swirling flow structure influenced by a distorted inflow of the volute is quite different, which indicates the importance of interaction of impeller with volute in the numerical simulation for volute.