Experiments on the flow past spheres at very high Reynolds numbers

The present work is concerned with the flow past spheres in the Reynolds number range 5 × 10 4 les Re les 6 × 10 6 . Results are reported for the case of a smooth surface. The total drag, the local static pressure and the local skin friction distribution were measured at a turbulence level of about 0·45%. The present results are compared with other available data as far as possible. Information is obtained from the local flow parameters on the positions of boundary-layer transition from laminar to turbulent flow and of boundary-layer separation. Finally the dependence of friction forces on Reynolds number is pointed out.