Numerical Investigation of Drag Reduction on Flat Plates using Dents
Drag Reduction, Dents, RANS, CFD, Skin friction
Drag force in vehicles – auto motives, aircrafts, ships and submersibles – result in increased fuel consumption. Various researches had been conducted to minimize the drag forces in terms of passive methods as well as active methods. This research focused on studying the influence of dents on flat plates over the drag coefficient. The dents were defined by three parameters – depth of the dent, main radius of the dent, diameter of the dent. A total of seven dent configuration was studied for flow conditions of 5 m/s to 40 m/s. The study was conducted with the help of computational fluid dynamics (CFD) simulations in ANSYS FLUENT. Pre-processing activities such as meshing was performed in ANSYS Work Bench. Necessary mesh refinement near the plate wall was provided to predict the skin friction components. Reynolds Averaged Navier-Stokes (RANS) formulation was employed in the simulation with the two equation SST k-omega turbulence model. With the increase in flow velocity, the drag coefficient was observed to increase. The results obtained indicate the drag reduction of nearly 30% by providing dents on the flat plate. This was observed for the flow condition of 10 m/s to 40 m/s for the dent plate -1. However, the drag reduction from the remaining configurations was minimal. The results were compared against the existing experimental data for the validation.