In many turbo machinery applications the working fluid is a mixture of a gas and a liquid. In such two-phase flows the liquid phase can be assumed to be a dispersed droplet flow. As the fluid passes the blades, a part of the droplets is deposited on the blades and forms a thin liquid film. At the trailing edge the thin liquid film separates and forms secondary droplets.
In this paper the ability of numerical investigations to study the size of secondary droplets is analyzed. In a first step a program solving the Thin Film Equations is used to analyze the film flow on the inlet guide vanes of an axial compressor. Secondly a CFD study with a Free Surface Model is performed to analyze the film stripping process. The ability of the Free Surface model to investigate film separation is validated against third party experimental results and the pro and contras of the Free-Surface model are presented. In the last step the stability of the formed droplets is investigated and the final droplet size is calculated.