CFD Benchmarking of Heat Transfer and Pressure Drop Predictions in a Pin Fin Channel

Abstract

At operating conditions, the turbine inlet temperatures in gas turbine engines exceed the melting point of the materials the turbine blades are made from. To ensure smooth operation at very high temperatures, turbine blades are cooled using various types of cooling air flow channels that facilitate heat transfer. Pin fin channels are commonly used on the trailing edge of the blades, where they enhance heat transfer and also provide structural support. In the design process several commercially available RANS turbulence models in CFD are used to predict the performance of the various pin fin channel cooling configurations. The purpose of this study is to validate the accuracy of the various CFD turbulence models, comparing Nusselt numbers and pressure coefficients against a valid set of experimental data obtained from well-established articles of literature. The need for accurate CFD predictions is aimed at the industrial need for more cost effective testing models. Turbulence models investigated are: realizable k-e, Menter’s k-ω SST, and a quadratic formulation of the realizable k-e model. The geometry investigated is a staggered 8 row pin fin channel. Results have shown that depending on the location in the channel and Reynolds number, the QRK-E and KO-SST models match heat transfer experimental data the closest. Comparisons have also shown that depending on Re, the RK-E and QRK-E models match pressure coefficient data the closest.