ABSTRACT
The modelling of the machine was done in two steps. Since flow conditions within a channel are complex in 3-D, the initial step consisted of setting up a 2D model for the wheel with straight blades. In the 3D model, the extension of the computational domain shows that the wall gaps play an important role in the filling and emptying of the chambers of the rotor. The computational mesh was divided into different parts to enable local refinement. General settings were identical to those of the 2D models consisting of the pressure based volume of fluid solver, explicit model with open channel flow, different cell zones for stationary domain and rotating mesh. In conclusion, the validated model shows the capability to predict power generation sufficiently for machine design. The application of Computational Fluid Dynamics provides a visualisation of the flow in detail.
