Multi-Blade Row Navier-Stokes Simulations of Fan-Bypass Configurations

Abstract

This paper describes extensions to a multi-blade row 3D Navier-Stokes solver to enable fan-splitter-bypass geometries to be handled. The code is applied to two generic configurations. The core-bypass splitter can exert considerable upstream influence via its associated pressure field and in the example shown here severely disturbs the fan suction surface boundary layer. The behaviour of the bypass ogv is substantially modified both by the clearance flow of the upstream fan and also by thicker than expected boundary layers on the splitter upper surface caused by the splitter LE incidence associated with the particular bypass ratio selected for the example.