Within Collaborative Research Center (SFB) 561 "Thermally Highly Loaded, Porous and Cooled Multi-Layer Systems for Combined Cycle Power Plants" at RWTH Aachen University an effusion-cooled multi-layer plate configuration is investigated numerically by application of a 3-D in-house fluid flow and heat transfer solver, CHTflow. The geometrical setup and the fluid flow conditions derive from modem gas turbine combustion chambers and bladings.Within the SFB two different multi-layer systems have been investigated: one system consisting of substrate made of CMSX-4 (a single-crystal super-alloy), an MCrAlY-bondoat and a ZrO2 thermal barrier coating and one system consisting of a NiAl-alloy and a graded bondcoat/TBC. The grading will increase the life-span of the TBC as it can compensate the different thermal expansion coefficients of the different materials better. The main focus in this study is on the different substrate materials, though: the thermal conductivity of the NiAl is considerably higher than that of CMSX-4, which leads to different temperature profiles in the components.The numerical grid for the simulations contains the coolant supply (plenum), the solid body for the conjugate calculations and the main flow area on the plate. The effusion-cooling is realized by finest drilled shaped holes with a diameter of 0.2 mm.The investigations concentrated on a cooling hole geometry with a laterally-widened fan-shaped outlet, contoured throughout and one without lateral widening that is only shaped in the top 0.25 of the system. Two blowing ratios M=0.28 and M=0.48 were investigated, both for a hot gas Maeh number of 0.25. The results for the lower blowing ratio and the fully contoured hole will be discussed here as well as those of the higher blowing ratio and the non-laterally widened hole. These represent two characteristic cases.The in-house code CHTflow is used for these calculations.CHTflow is a conjugate code, which yields information on the temperature distribution in the solid body. This enables a detailed discussion of the effects of a change in materials.
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