基于CFD的ROV航速预报

Speed Forecast of ROV Based on CFD

基于计算流体动力学(Computational Fluid Dynamics,CFD)理论,根据剪切应力传输(Shear Stress Transfer,SST)模型k-ω湍流模型数值求解和雷诺平均方程(Reynolds-Averaged Navier-Stokes equation,RANS)原理,通过切割体网格划分法计算三自由度运动模式下遥控无人潜水器(Remotely Operated Vehicle,ROV)的二阶阻尼系数、线性阻尼系数、ROV附加质量,建立ROV三自由度动力学模型。采用STAR-CCM+计算单个导管螺旋桨的各水动力数值,考虑ROV对导管螺旋桨的影响,计算其水动力性能。在此基础上,进行ROV动力与阻力的匹配,提出一种基于回归曲线法的航速预报方法以实现ROV航速预报。结果表明:单独螺旋桨产生的推力之和可作为ROV的总推力;在固定螺旋桨转速的情况下,在预估航速附近设置多个航速点,通过迭代法和回归曲线的方法确定此转速下推力与阻力相等的航速点,可实现螺旋桨不同转速下ROV航速的预报。

Based on the Computational Fluid Dynamics(CFD)theory,according to the Shear Stress Transfer(SST)k-ωturbulence model numerical solution and the principle of Reynolds-Averaged Navier-Stokes equation(RANS),the second-order damping coefficient,linear damping coefficient and additional mass of Remotely Operated Vehicle(ROV)in three-degree-of-freedom are calculated by the cut volume meshing method,so as to establish the three-degree-of-freedom dynamic model of ROV.The hydrodynamic values of the single ducted propeller is calculated with the help of STAR-CCM+software,and the hydrodynamic performance of the ducted propeller is calculated by considering the influence of ROV.On this basis,the ROV power is matched with ROV resistance,and a speed prediction method based on regression curve method is proposed to realize the speed forecast of ROV.The results show that:the sum of the thrust generated by the individual propeller can be used as the total thrust of the ROV;under the condition of fixed propeller speed,multiple speed points are set near the estimated speed,the iteration method and regression curve method are used to determine the speed point with equal thrust and resistance at this speed,so as to realize the ROV speed forecast at different propeller speeds.