Comparison of Heat Transfer Prediction for Various Turbulence Models in a Pin Fin Channel

Abstract

Heat transfer augmentation through the use of pin fins is commonly employed in gas turbine blades and vanes. This is particularly true in the trailing edge region, where the pin fins provide additional structural support, flow control, and heat transfer enhancement. In the industrial design process, commercial CAE packages are now routinely used for predicting the performance of such cooling configurations. The designer is often left with the timeconsuming task of validating their approach. The present study will investigate the accuracy of a selection of the turbulence models commercially available, comparing Nusselt numbers against those found in selected, well-established articles from the literature. With the industrial importance of simulation turn-around time in mind, this investigation will compare 4 RANS turbulence models, at various levels of mesh refinement and temporal resolution. Turbulence models investigated are: realizable k-ε, Menter's k-ω SST, the v 2 -f model, and a quadratic formulation of the realizable k-ε model. The geometry investigated is a staggered, 10 row pin-fin channel, with S/D= 2.19, H/D= 0.875, X/D=1.32, at a Reynolds number of 52.8k. Results show that quadratic versions of the realizable k-ε model tend to match between 6% and 21% of the experimental Nusselt number results on the surface of the pin. Nomenclature CFD = Computational Fluid Dynamics D = Pin Diameter (m) H = Channel Height (m) h = Heat Transfer Coefficient (W/m 2 K) Nu = Nusselt Number S = Spanwise Distance (m) q" = Heat flux (W/m 2 ) RANS = Reynolds Averaged Navier Stokes Re = Reynolds Number T s = Wall Temperature (K) T ref = Reference temperature (K) X = Streamwise coordinate (m)