Efficient Turbine Cooling Design: From 2D Concept to 3D CAD Modeling

Abstract

In order to improve the thermal efficiency of gas turbines, efficient cooling concepts for turbine vanes are becoming increasingly important. However, evaluating the performance of a cooling design is computationally intensive and usually requires a coupled CFD-FEM simulation. This approach is not practical in the early design phase when the cooling design is frequently changed. To overcome this limitation, a simplified yet physical approach is required to develop an initial cooling design. This study presents a comprehensive approach for turbine vane cooling design that is integrated into an optimization tool chain. The model uses a vane geometry model, aerodynamic flow field, and coolant conditions from an internal turbine design tool chain. The cooling geometry is modeled in multiple radial sections using variable geometric parameters to account for variations in airfoil geometry and flow field. Both internal cooling, such as impingement or convective cooling, and external cooling, such as film cooling, are considered. This approach enables significant improvements in cooling design by reducing cooling air requirements as well as optimizing temperature distribution and thus minimizing thermal stresses during the early design phase. Consequently, a detailed 3D model of the vane is created with substantially reduced effort.