The transformation of the energy systems will call for new turbomachinery designs for harvesting low-grade heat. LTH has a project with the Swedish SME Climeon where our responsibility is to perform the design of a small stage steam turbine. From a design perspective, this is rather challenging and will call for high-fidelity CFD campaigns where the full 360 degree turbine annulus is analyzed. Due to the special working conditions of the turbine, a supersonic design together with partial-arc admission is un-avoidable. In partial arc admission, the flow is not admitted to one or several arcs of the inlet annulus. Since the one arc design has showed better performance in the previous research, the design need to be unsymmetrical and this requires the full annulus of the turbine to be modelled. In addition due to shock waves and the two phase flow problems, the estimated computational power is large. Therefore, the investigation is started with an application for medium size allocation however, the computational demand will need to apply for large allocations in the near future.