舰船典型隐身桅杆流体动力数值实验研究

Numerical experimentation on hydrodynamics of typical concealed mast of a war ship

该文以舰船棱柱型结构的隐身桅杆为研究对象,利用计算流体力学软件CFX和ICEM在不同雷诺数和攻角的条件下对模型进行数值实验,将数值实验所得到的各项结果与在哈尔滨工程大学船模拖曳水池中进行的实验数据相比较,结果表明通过数值实验方法可以进行定常力的求解,但是在脉动压力的求解时误差相对较大一些,在此基础之上提出了数值实验的改进方法。通过数值实验的方法研究了在不同雷诺数和不同攻角的条件下定常力、脉动压力、斯特诺哈尔数和脉动压力随攻角的变化趋势,发现攻角的变化不仅对定常力有影响,而且对脉动压力、斯特诺哈尔数和漩涡的发放也有着巨大的影响,并且不同攻角对应的斯特诺哈尔数在Re=6.38×105时候变化比较大,而在Re=9.57×105时变化幅度比较小。

ANSYS CFX 5.7 in conjunction with ANSYS ICEMCFD is used to numerically verify the vortex shedding pattern, the static forces, and the fluctuating forces acting on the prism shaped concealed mast of a warship. The numerical results are compared with those of experiments from towing tank and it draws a conclusion that the numerical methods can calculate well the static forces acting on the mast, while larger error exists in calculating fluctuating forces. On these bases, the numerical methods are improved. After doing the numerical experimentation at different Reynolds number and different attack angles, it is found that the changing of attack angle has great influence not only on the static forces, but also on the fluctuating forces, Strouhal number and the vortex shedding. Moreover, on the basis of experimental and numerical comparison it is concluded that Strouhal number changes with angle of attack most significantly at Reynolds number = 6.38 × 10^5 , while changes less at Reynolds number = 9.57 × 10^5.