Study of Separation Lines and Flow Patterns in 3D Boundary Layer Over Sphere Using Experimental and Numerical Analysis

Flow past three-dimensional bodies in general and flow separation in particular are complex compared to their two-dimensional counterparts. The complexity arises because flow now has an additional direction to maneuver in regions of adverse pressure gradient while taking path of least resistance. Even among three-dimensional bodies, flow past sphere, despite its outwards simplicity in shape, exhibits distinct features of three-dimensionality due to its surface curvature. In this paper, flow separation points at different location over sphere are studied, and flow patterns in rear section of the sphere are observed at different Reynolds numbers (0.02–0.1 million) using oil flow visualization in low speed subsonic wind tunnel. Numerical simulations are carried out in commercial software Ansys, and results obtained numerically are compared to the experimental results. Paper aims to find the relation between separation lines, Reynolds number (Re) and the shear stress patterns in three-dimensional boundary layer flows for the sphere from experimental and numerical analysis.