Eventos Anais de eventos
COBEM 2019
25th International Congress of Mechanical Engineering
OPTIMIZATION OF DRAG REDUCTION BY A DIFFERENT TRIP WIRES DIAMETERS VARIATION ON A SPHERE
Submission Author:
Vagner Ferreira de Oliveira , MG , Brazil
Co-Authors:
Vagner Ferreira de Oliveira
Presenter: Vagner Ferreira de Oliveira
doi://10.26678/ABCM.COBEM2019.COB2019-0811
Abstract
The characteristics of flow around a sphere with a different trip wires diameter was placed around the sphere at the angle of 55° measured from the frontal stagnation point were experimentally and RANS based Computational Fluid Dynamics method was investigated at the subcritical Reynolds numbers of 4+e5, has been carried out in the test section of closed circuit wind tunnel at Federal University of Minas Gerais. The best result reached with trip wire at 0.5 mm, the drag coefficient decrease 19% abruptly for smooth to 0.5 mm, after this trip wire dimension, the drag coefficient increases progressively to each diameter increment. The trip wires produces even larger disturbances through the separation and reattachment right at the trip-wire location for higher Reynolds numbers, the boundary layer flow becomes turbulent soon after on itself location and the main separation is delayed. Then, the main separation is delayed due to high momentum near the surface and the drag is significantly reduced.
Keywords
trip wire, CFD, Wind Tunnel, sphere., drag force
