Numerical Flow Analysis in a Subsonic Vaned Radial Diffuser With Leading Edge Redesign
The flow field in a subsonic vaned radial diffuser of a single stage centrifugal compressor is numerically investigated using a 3D Navier-Stokes solver (TASCflow) and a 2D analysis & inverse-design software package (MISES). The vane geometry is modified in the leading edge area (2D blade shaping) using MISES, without changing the diffuser throughflow characteristics. An analysis of the 2D and 3D effects of two redesigns on the flow in each of the diffuser subcomponents is performed in terms of static pressure recovery, total pressure loss production and secondary flow reduction. The computed characteristic lines are compared with measurements, which confirm the improvement obtained by the leading edge redesign in terms of increased pressure rise and operating range.