PASSIVE CONTROL OF THE FLOW AROUND A CYLINDER BY USING GEOMETRIC MODIFICATIONS

The present study is aimed at reducing the drag loads on cylinders by using a passive control technique which consists in shape modifi cation for streamlined and bluff bodies, particularly those used in aeronautics. Various shapes of elliptic and ovate-elliptic cross sections were tested with studying the eff ect of geometric parameters, namely, the radius ratio and axial ratio. The fl ow around the proposed geometries was studied numerically using k–ε, k–ω, and Spalart–Allmaras turbulence models at the Reynolds numbers from 10⁴ to 2.4∙10⁴ . The results obtained were compared with those for a circular cylinder of constant radius, showing a signifi cant weakening of aerodynamic forces acting on the cylinder with modifi ed shapes, especially at high Reynolds numbers, for both elliptic and ovateelliptic geometries with a better performance for the latter
The present study is aimed at reducing the drag loads on cylinders by using a passive control technique which consists in shape modifi cation for streamlined and bluff bodies, particularly those used in aeronautics. Various shapes of elliptic and ovate-elliptic cross sections were tested with studying the eff ect of geometric parameters, namely, the radius ratio and axial ratio. The fl ow around the proposed geometries was studied numerically using k–ε, k–ω, and Spalart–Allmaras turbulence models at the Reynolds numbers from 10⁴ to 2.4∙10⁴ . The results obtained were compared with those for a circular cylinder of constant radius, showing a signifi cant weakening of aerodynamic forces acting on the cylinder with modifi ed shapes, especially at high Reynolds numbers, for both elliptic and ovateelliptic geometries with a better performance for the latter
Author:  F. Djemil, O. Ladjedel, F. Zemani, M. Belharizi, T. Yahiaoui, L. Adjlout
Keywords:  fl ow control, cylinder shape modifi cation, pressure coeffi cient, drag coeffi cient
Page:  1326