Analytical Modeling of Radial Fluid Migration in the Boundary Layer of Axial Flow Turbomachinery Blades

The paper presents an analytical model for qualitative prediction of physical effects stimulating or retarding the radial outward migration of high-loss fluid in the suction side boundary layer of the blades of isolated axial flow rotors. This fluid motion is considered as the main cause of tip stalling. In elaboration of the model, the radial acceleration of fluid particles is expressed, and the Reynolds-averaged Navier-Stokes equation is applied for description of flow. On the basis of the model, guidelines are formulated in order to retard the inception of stall.