Effects of turbulence modeling in predicting flow and heat transfer in a duct with pin fins

Christelle Wanko Tchatchouang, Purdue University

Abstract

Computations based on steady RANS with and without conjugate analysis were performed to study the effects of turbulence models in predicting the flow and heat transfer in a high-aspect ratio rectangular duct lined with a staggered array of pin fins with circular cross sections. The turbulence models examined are the shear-stress transport (SST) model and the stress-omega Reynolds stress model (RSM). In all simulations, the mesh was fine enough so that wall functions were not employed and integration of all equations is to the wall. Since RSM naturally accounts for streamline curvature, anisotropy of the Reynolds stresses, and the time-lagged response of turbulence to changes in the mean flow, predictions from RSM were used to assess the results from the SST model on the flow structure and surface heat transfer. Results obtained show how different models capture the key flow features created by a staggered array of pin fins—namely the horseshoe vortex at the pin fin-wall junction, the wake behind each pin fin, and their interactions - and how those flow structures affect surface heat transfer. Results are also obtained to show the differences in the predicted heat transfer coefficient with and without conjugate analysis.

Degree

M.S.A.A.

Advisors

Shih, Purdue University.

Subject Area

Engineering|Mechanical engineering

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