This paper deals with the simulation of steady flows in turbomachinery. Two approaches are proposed, the first one is the classical multiple-rotating frame method (MRF) by multi-zone approach where the different zones are separated by non-overlapping interfaces and solved independently. Since each zone is loaded separately, a transferring system should be properly implemented at the interface boundaries. Two techniques are considered, in the first one the conservative variables are interpolated between zones while in the second one the fluxes are transferred through the interfaces.
The other proposed approach is a new version of the MRF using a virtual interface (VMRF). This is a simplified of the previous one where the interfaces are created virtually at the solver level, rendering the method easy to implement especially for edge-based numerical schemes, and avoiding any re-meshing in case one needs to change interface position, shape or simply remove or add new one. Finally, numerical tests are performed to demonstrate the efficiency of the proposed methods by comparison with commercial codes (ANSYS FLUENT).