A finite-volume method for the conjugate heat transfer in film cooling devices

Abstract

The present work concerns the activity performed to upgrade an in-house finite-volume computational fluid dynamics solver for computing heat transfer in gas turbine cooling devices. The ‘conjugate simulation’ of fluid heat transfer and metal heat conduction has been considered. To this aim the original code has been coupled to a new one solving the Fourier equation in the solid domain. This modification allows the ‘conjugate heat transfer’ investigation in the fluid and solid domains at the same time. Moreover an external radiation source can be modelled having included an extra term for the energy balance at solid—fluid interface. The approach has been validated through two different test-cases. The first one is a two-dimensional laminar flow over a flat plate, the second one is a film-cooled plate. The code uses conformal meshes, without using interpolation functions at the interfaces. This allows the study of configurations more complex than those in the open literature, such as the complete film-cooled stage shown in this work. In this example the complete cooling system of the nozzle has been modelled, including the two plenums and six rows of cooling channels as well. The conjugate heat transfer (CHT) has been evaluated on rotor blades as well.