Effect of streamwise length on the wake characteristics of elongated bluff bodies with small ground clearance

Abstract

This paper analyzes the effect of streamwise length on the flow characteristics of elongated bluff bodies with small ground clearance using the Reynolds stress turbulence model. A fully developed turbulent boundary layer approach flow was specified as the inlet condition. Three cases with different elongation ratios (L/h) were considered for this analysis and a fourth case was employed for the validation of the simulation. Case A had an elongation ratio (L/h) of 1.0 while cases B and C had L/h of 2.0 and 3.0, respectively. The simulation was conducted at a Reynolds number Reh of 22500 for all cases. The mean velocities and Reynolds stresses are evaluated to gain a physical understanding of the flow dynamics around the bodies. The results showed that the flow passes over the body without any visible flow reattachment along its surface for case A. Cases B and C demonstrated flow reattachment occurring upstream of the trailing edge. However, in case B, the flow reattachment was of a shorter length and closer in proximity to the trailing edge. I.