Boundary-Layer Control as a Means of Reducing Drag on Fully Submerged Bodies of Revolution

The drag of axisymmetric bodies can be reduced by boundary-layer suction, which delays transition and can control separation. In this study, boundary-layer transition is delayed by applying a distributed suction technique. Optimization calculations were performed to define the minimal drag bodies at Reynolds numbers of 10⁷ and 10⁸. The saving in drag relative to optimal bodies with non-controlled boundary layers is shown to be 18 and 78 percent, at Reynolds numbers of 10⁷ and 10⁸, respectively.