Hydrodynamic structure of the boundary layers in a rotating cylindrical cavity with radial inflow

Abstract

A flow model is formulated to investigate the hydrodynamic structure of the boundary layers of incompressible fluid in a rotating cylindrical cavity with steady radial inflow. The model considers mass and momentum transfer coupled between boundary layers and an inviscid core region. Dimensionless equations of motion are solved using integral methods and a space-marching technique. As the fluid moves radially inward, entraining boundary layers develop which can either meet or become non-entraining. Pressure and wall shear stress distributions, as well as velocity profiles predicted by the model, are compared to numerical simulations using the software OpenFOAM. Hydrodynamic structure of the boundary layers is governed by a Reynolds number, Re, a Rossby number, Ro, and the dimensionless radial velocity component at the periphery of the cavity, U-o. Results show that boundary layers merge for Re << 10 and Ro >> 0.1, and boundary layers become predominantly non-entraining for low Ro, low Re, and high U-o. Results may contribute to improve the design of technology, such as heat exchange devices, and turbomachinery.