A Hybrid Coupling Scheme and Stability Analysis for Coupled Solid/Fluid Turbine Blade Temperature Calculations

Efficient thermal design of turbine blade cooling needs to take wall temperature effects on heat transfer into account. This can only be achieved by a coupled calculation of hot gas flow and blade heat conduction. In this paper principle and stability proof of an algorithm are presented that allows to couple a steady state finite element heat conduction solver with a blockstructured steady state finite volume (FV) Navier-Stokes time marching flow solver. The stability of the developed coupling procedure as well as the instability of an alternative algorithm is shown analytically and numerically. The benefits of coupled calculating are shown for a convectively cooled turbine guide vane blade. In the example treated, temperature differences of more than 100 K arise compared to the same calculation performed in an uncoupled way.