Boundary Layers, Separation, Lift and Drag - External Flows - Engineering Sciences Previous Year Questions

Flow-separation from a solid surface may take place if the flow is

For a laminar boundary layer with constant freestream velocity (i.e. dp/dx = 0), the variation of ∂u/∂y with distance from the wall is given by

Air flowing over a smooth cylinder of diameter 30 cm in a wind tunnel produces a two-dimensional laminar boundary layer that separates from the surface of the cylinder. The surface of the cylinder is then roughened with sand paper so that the boundary layer turns turbulent. The location of the point of separation will

Air from the blower of a hairdryer flows between two identical elliptical cylinders suspended freely, for two cases shown in the figure. The cylinders would move

A cricket ball comprises of a seam running along its central section, which is essentially stitching of two hemi-spheres. The seam creates additional roughness. The bowler releases the ball with seam orientation as shown in the figure below. This would result in an out swinger with side forces on the cricket ball. These side forces on the ball are attributed to

Bodies with various cross-sectional shapes subjected to cross-flow of air are shown in the following figures. The characteristic dimension of all the shapes is the same. The cross-sectional shape with the largest coefficient of drag (i.e. sum of the pressure and skin-friction drags), at any moderately large Reynolds number, is