Conjugate Heat Transfer Simulations for a Film Cooled Nozzle Guide Vane of a High-efficiency, Industrial Gas Turbine

International audienceGreat efforts are still put into the design process of advanced film-cooling configurations. In particular, the vanes and blades of turbine front stages have to be cooled extensively for a safe operation. The conjugate heat transfer (CHT) calculation technique is used for the three-dimensional thermal load prediction of an extensively cooled 1 st nozzle test vane installed in a highest-efficient industrial gas turbine. With the CHT approach it is possible to take the interaction of internal flows, external flow, and heat transfer into account without estimation of heat transfer coefficients. The utilized numerical model contains all geometrical features (e.g. pin-fins, ribs, impingement sheets etc.) of the real test vane without simplifications. The comparison with thermal index paint measurements inside the test engine shows that a qualitatively and quantitatively good agreement between the CHT and the measurements results can be found. A consideration of advanced-shaped film cooling holes at the vane platforms also offers high potential to further reduce the material temperatures and decrease thermal stresses by lowering of platform temperatures and homogenization of the temperature distribution