Numerical Analysis of Compressible Fluid Flow in Narrow Gaps

Fluid flow in a narrow gap is a characteristic problem in fluid mechanics. In today’s turbomachines several applications are based on the phenomena of two surfaces being separated by a thin fluid film of only a few micrometers. In this contribution a numerical model is introduced to determine flow characteristics of compressible fluids, contained between two concentric non contacting rotating rings. The model is based on the assumption of a laminar viscous flow field and isothermal conditions. Furthermore it takes aerostatic and aerodynamic effect into account. A finite difference approach to solve the models governing equation is described and methods to improve convergence are introduced. To perform the established numerical model on a wide variety of geometric configurations an interface between a 3D-CAD design software and the numerical model has been developed and is presented in this paper.