拖体水动力特性的流体力学分析

Hydromechanical Analysis of Towed Body on Hydrodynamic Characteristics

根据Airy微幅波波浪理论和不可压缩的黏性流动Navier-Stokes方程对拖体的水动力特性作理论分析,建立海水中拖体运动响应方程,推导出波浪和水下作业中拖体受力运动计算方法,利用水动力分析软件AQWA对试验拖体的三维模型进行仿真计算。对拖体在波浪中运动响应进行频域分析,计算出拖体运动响应放大因子RAO曲线,发现当波浪频率越大,拖体俯仰响应越大,最大俯仰响应角度数值可达约11倍有义波高数值;参考试验海域海况参数,对试验拖体在波浪中运动响应进行时域分析,计算100 s内拖体升沉、纵摇、横摇和偏航位移响应。计算结果预警当有垂直拖体长度方向的波浪入射时,拖体会产生较大的横摇、偏航。通过仿真数据和实际试验数据的对比可以看出,采用的计算方法对试验拖体运动响应作出的预报值准确、可靠。

The hydrodynamic characteristics of the towed body are analyzed theoretically based on the Airy wave theory and incompressible viscous flow Navier-Stokes equation,and the motion response equation of the towed body in seawater is established.The calculation method of the towed body in waves and underwater operation is derived.And the hydrodynamic force of the towed body is simulated by AQWA.The frequency domain response of the towed body is analyzed and the motion response RAO curve of the towed body is calculated.According to the results,the wave frequency is greater,the pitching response of the towed body is bigger.And the maximum pitching response angle value can reach about 11 times than the wave height.With reference to the sea state parameters of the test area,the time domain response of the towed body is analyzed and the depth,pitch,roll and yaw displacement responses are calculated in 100 s.Through the comparison of the simulation data and the working results,it can be found that the simulation calculation method used can predict the motion response of the towed body reliably.