DRAG REDUCTION OF A SUBMERSIBLE HULL BY ELECTROLYSIS

Viscous drag reduction of a fully-submerged body of revolution is obtained by creating hydrogen gas on the hull by electrolysis. The bubbles alter both the laminar and turbulent boundary-layer characteristics resulting in a significant reduction in the viscous drag on the 3-foot model up to a speed of 8.5 feet per second, the maximum test velocity. Results show that the amount of drag reduction depends on the ratio of the mass flow of water in the wake to the time-rate of hydrogen mass produced beneath the boundary-layer. The results presented herein are model results and should NOT be considered directly applicable to any existing prototype.