Flow Topology Optimization of a Cooling Passage for a High Pressure Turbine Blade

This paper deals with a topology optimization of internal cooling passages within high pressure turbine blades in order to deliver fully three dimensional designs that optimize the local flow physics. By applying the implemented optimality criteria, a new individual passage design with minimized amount of recirculation is achieved, leading to a reduced total pressure loss. In contrary to traditional parametric approaches, where a CFD run is needed after each design modification, the applied topology optimization acts as a co-simulation and is finished after a single run where the initial geometry represents the available design space. The CFD runs for optimization and the subsequent verification of the flow passages assume steady state take-off conditions. The verification includes a flow simulation to check the pressure loss of the optimized passage design. In a second step, a loosely coupled conjugate heat transfer procedure including external turbine flow, coolant flow and heat conduction of the solid (blade, platform and attachment) is applied to predict the impact on the heat transfer. By running a FEM simulation afterwards, the stresses are computed and compared with those from the reference design.