The fluid flow characteristics around a triangular grooved cylinder.

The purpose of this research is to reveal the effects of roughness on the hydrodynamics of the fluid around a grooved cylinder by studying the drag and recirculation length. The main objectives are to reach the maximum reduction of the wind load. This work is carried out to investigate the effect of the number of grooves on the drag reduction of flow around a circular cylinder with triangular grooves. This investigation reports numerically on a laminar steady flow over a cylinder with 2, 4, 8, 12 and 16 triangular grooves regularly distributed around the cylinder circumference with wavelength and wave amplitude of 1/10, immersed in two-dimensional unconfined Newtonian fluid over the symmetry regimes. The predicted results showed an excellent agreement with the available data of literature for validation. The obtained results used for our investigations for a Reynolds number up to 40 suggest that the presence of the grooves on the smooth cylinder surface leads to a slight reduction over the drag coefficient and the recirculation length at the same Reynolds number, this trend is more pronounced as the number of grooves increase. [ABSTRACT FROM AUTHOR]