A CFD model was developed for simulations of effusion cooled structures like combustor liners or turbine blades. The main problem in such simulations is the mesh size, since the inclusion of the effusion cooling holes in the mesh rapidly increases the mesh size, which leads to very high computational costs. The present model circumvents this problem by replacing the effusion cooling holes with a set of mass sinks on the cold side of the cooled surface and mass sources on the hot side of the cooled surface. Furthermore, in case of a conjugate heat transfer simulation, heat sinks can be added inside the structure to account for heat loss due to convective cooling. In these cases the heat which is removed through the heat sinks is added to the mass sources as an increase in temperature. Each cooling hole is represented by one mass sink, one mass source and one heat sink in cases which include conjugate heat transfer. The main advantage of the model is a low requirement regarding the spatial resolution of the computational mesh. Node distances in the area around the cooled surface can be chosen to be as large as the effusion hole diameter. For a first validation the model has been applied to a test case comprising an effusion cooled flat plate with 7 rows of staggered cooling holes including conjugate heat transfer. Simulations of the test case show good agreement with experimental results. In this first test case the mass flow through all cooling holes was assumed to be equal. However, in realistic geometries, which include complex flows like recirculating or swirling flows, the mass flow through each cooling hole might be different, depending on the pressure distribution along the cooled surface. Therefore the model will be extended to be able to calculate the mass flow through each cooling hole separately depending on the pressure drop through the hole.

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