Study of two turbulence models in predicting the drag of a bluff body

Abstract

Drag reduction on a two dimensional D-shaped bluff body is numerically studied. In this research, mesh independence study is carried out at the same velocity value of 10m/s. The effect of Reynolds number on the drag coefficient is also carried out. This was done by increasing the inlet velocity from 10m/s to 60m/s hence increasing the Reynolds number. The k- and SST turbulence models are used and also their suitability for predicting the drag is compared in this study. Preliminary results on drag forces are presented here. The preliminary results suggest that the drag values obtained for our two-dimensional bluff body is mesh independent. The results also show that the drag coefficient remains nearly constant with increase in Reynolds number. The study show that the SST turbulence model underpredicts the drag coefficient compared to the k- turbulence model.