The use of Computational Fluid Dynamics (CFD) and Computational Continuum Mechanics (CCM) for analysis of rotary positive displacement machines is exponentially increasing. The main factor which allowed this is the availability of methods for generating structured body fitted, transient and moving numerical grids of complex domains such as screw compressors. This allows fully conservative solution but has challenges in ensuring good quality for all numerical cells which may cause some numerical dissipation.
Some methods have evolved which use overlapping or cut-Cartesian meshes but these have problem with conservativeness and representation of clearances which requires very large grids and special treatment of leakage flows.
Therefore several challenges still exist when using the commercial CFD/CCM which affect the speed and accuracy of 3D CFD modelling. Topics discussed in this webinar include conservativeness, numerical instabilities and dissipations as well as the speed and accuracy of calculating multiphase models for positive displacement machines.