由于海底边界效应和复杂多变地形的影响,对水下自航行器(autonomous underwater vehicle,AUV)的运行稳定性和操纵性提出了更高要求,本文针对近海底处AUV的水动力性能进行了建模与分析,预测并控制AUV在近海底处的运动。利用计算流体力学方法和ANSYS ICEM软件对近海底处的AUV进行六面体结构网格划分,然后利用Fluent对近海底流场进行数值模拟仿真和分析,结合仿真结果分析了距海底的距离、航行速度、攻角、前方下面斜坡倾角大小和斜坡水平长度对水下自航行器特性的影响。结果表明,在距海底1500mm时,海底壁面就几乎不再影响AUV的水动力性能;攻角为0°航行时,AUV会受到向下的力;随着前方下面的斜坡倾角大小和斜坡水平长度的增加,其阻力系数减小。
In this paper,the hydrodynamics performance of AUV near the sea bottom was conducted for prediction and control of AUV motion. First,the hexahedral mesh of the AUV was generated using the computational fluid dynamic method and ANSYS ICEM software. Then the numerical simulation and analysis of AUV in the bottom fluid field was carried out using Fluent. The influences of different distances between AUV and sea bottom,submarine speed,attack angle,angle of right ahead of AUV and slope length on the stability and maneuverability were analyzed and compared using the results of numerical simulation. it shows that the AUV's hydrodynamic characteristic remains stable under the distance of 1500mm; When attack angle α = 0°,AUV is under the influence of attraction from sea bottom; The drag coefficient decreases with the increase of the angle of right ahead of AUV.