Abstract

To improve the drag reduction performance of underwater vehicles, a skin composed of micro floating raft arrays and a bionic compliant wall is proposed. The micro floating raft is a miniaturization of the floating raft system which is widely used in vibration and noise reduction. The drag reduction characteristics of the skin with various structural parameters are simulated with the IB2d software based on the immersed boundary method. A considerable reduction (up to 15%) in the viscous force is observed for the skin with a certain range of l*, i.e., the spacing between the micro floating raft arrays, which is resulted from the decrease of the velocity near the wall and the increase of the boundary layer thickness. Meanwhile, the drag reduction performance of the skin is also improved by increasing the porosity coefficient α* of the compliant wall, as well as the stiffness ratio γ* and the intermediate mass m* of the micro floating raft, within limits. This study provides a new idea for designing the coating of underwater vehicles and reveals the corresponding drag reduction mechanism to a certain extent.

摘要

为了提高水下航行器的减阻性能，提出了一种由微浮筏阵列和仿生柔顺壁组成的蒙皮。微型浮筏是浮筏系统的小型化，广泛应用于减振降噪。基于浸入边界法，利用IB2d软件模拟了不同结构参数蒙皮的减阻特性。对于具有一定l范围的皮肤，观察到粘性力显着降低（高达 15%）。*，即微浮筏阵列之间的间距，是由于壁面附近速度减小和边界层厚度增加造成的。同时，通过在一定范围内提高柔顺壁的孔隙系数α * 以及微浮筏的刚度比γ * 和中间质量m * ，也提高了蒙皮的减阻性能。该研究为水下航行器涂层设计提供了新的思路，并在一定程度上揭示了相应的减阻机理。