Arrangement and Control Parameter Selection Methods for Achieving High-Efficiency Underwater Active Drag Reduction by Micropiezoelectric Actuator

The improvement of sailing speed and endurance of microunderwater vehicle can be achieved by reducing the wall friction drag. We proposed a piezoelectric drag reducer (PDR), which can be embedded into the wall of the underwater vehicle without affecting the original streamline. We discussed the drag reduction characteristics of the PDR with different arrangement angles based on the simulation analyses, and a maximum friction drag reduction rate of 45.3% can be achieved when the arrangement angle between the direction of PDR and the incoming flow is 60°. The influences of key parameters on the turbulence characteristics are obtained with a view to select control parameters for meeting different drag reduction requirements. In order to verify the simulation results, we carried out experimental tests, the experimental data have been analyzed using turbulence statistical method. The relative errors of friction drag reduction results between simulation and experiment are less than 12%, which proved the effectiveness of the proposed arrangement and control parameter selection methods. Then, the feasibility of achieving high-efficiency active drag reduction of microunderwater vehicle, based on the proposed PDR, is verified to be effective according to the test results of total drag experiments.