This work involves CFD conjugate heat transfer modelling of the geometrical design influence on effusion cooling. Experimental data was modelled for the overall effusion film cooling effectiveness using Nimonic 75 walls with imbedded thermocouples. The Fluent CFD code was used to investigate the experimental configuration for a 10×10 square array of holes with a 90° injection angle. In the computational predictions, 10000ppm of methane tracer gas was added to the coolant and the concentration at the wall allowed the adiabatic cooling effectiveness of the effusion film cooling to be predicted separately from the overall wall cooling effectiveness. The predicted overall cooling effectiveness results show that the wall was locally at a uniform temperature, but the axial development of the cooling film does result in a gradual reduction of the wall temperature with axial distance. The predictions show that the heating of the coolant by the hot wall was equally split between the hole approach flow on the backside of the wall and inside the film cooling holes. This heating changed the conditions in the film cooling layer from those of the equivalent adiabatic wall. There was good agreement between the conjugate heat transfer predictions of the overall cooling effectiveness with the experimental data.

This content is only available via PDF.
You do not currently have access to this content.