回转状态下导管螺旋桨水动力特性的数值模拟

Numerical Simulation of Hydrodynamic Characteristics of Ducted Propeller in Turning Motion

采用滑移网格技术和计算流体力学方法,在导管螺旋桨所在的流域内求解其N-S方程,以此模拟在作回转运动的水下机器人流场作用下导管螺旋桨的推力特性,观察螺旋桨在这一环境下的水动力现象.计算结果表明:当来流从尾部流向机器人时,对于尾导管螺旋桨,有机器人影响时其推力系数比无机器人时要小,对处于机器人舷侧的螺旋桨,有机器人时其推力系数比无机器人时要大;当来流从首部流向机器人时其情形刚好相反;而当机器人轴线与流向大致垂直时,有无机器人对螺旋桨推力系数的影响不大.

In this paper,first,the sliding mesh technology and the computational fluid dynamics （ CFD） technology are both applied to solve the Navier-Stokes equations of a ducted propeller which governs the fluid motion around the duct. Then,the thrust characteristics of the ducted propeller in the flow field of an underwater robot in turning motion are simulated,and the hydrodynamic phenomenon of the propeller in such a condition is observed. The results indicate that,when the flow comes from the robot stern,the thrust coefficient of the stern propeller is lower while that of the side propeller is higher than that without robot,that the flow from the robot frontage may result in an opposite case,and that the robot has no obvious effect on the thrust coefficient when the direction of incoming flow is approximately perpendicular to the axis of the robot.