The project at KTH aims to enhance the understanding of the non-isothermal unsteady fluid flow downstream of the RDC interacting with the high-pressure axial turbine stage and to develop optimal flow control blade cooling solutions within this context. Commonly, flow control strategies are used for enhancement of heat transfer in high-pressure turbines (e.g., air film cooling). However, it is also common that these flow control strategies are applied to an already optimized turbine blade configuration. The proposed approach with this project is to integrate from the beginning into the optimization process the flow control technology to be used. Supersonic flow conditions associated with the high-pressure axial turbine cascade are to be assessed. Unsteady high-fidelity simulations based on Large Eddy Simulation approach are to be carried to understand the behaviour of secondary flows and assessment of the high-pressure turbine performance and heat transfer under relevant RDC operating conditions. Sensitivity to the operating and boundary conditions will be assessed (including impact of non-isentropic temperature fluctuations).