两栖车航行阻力特性的数值研究

Numerical Study on Sailing Resistance Characteristics of Amphibious Vehicle

针对高速两栖车水上航行阻力特性问题,采用基于雷诺平均方程的有限体积法对静水中高速两栖车的阻力及航态进行了数值模拟。通过不同网格密度的阻力比较,对网格收敛性进行了讨论;通过与模型试验结果的对比,对文中采用的数值计算方法进行了验证。另外,结合叠模计算结果对两栖车的各阻力成分进行了分析。在此基础上,计算分析了带开口的两栖车模型的阻力及航态变化。结果表明:处于过渡阶段的两栖车,其兴波阻力占总阻力的比例随航速增加而增加(最高可达到60%以上),黏压阻力占比30%~40%,摩擦阻力占比小于10%;增加开口后两栖车的阻力增加,在Fr_(▽)=1.297时阻力增大约11%,车体下沉深度增大约5%;与无开口状态相比,有开口两栖车的各个阻力成分的占比发生变化,兴波阻力占比减少,而黏压阻力占比增加。

Numerical simulation of the resistance and sailing state of high speed amphibious vehicle in still water was conducted with the finite volume method based on Reynolds averaged equation to obtain the resistance characteristics of high speed amphibious vehicle in water.The mesh convergence of mesh was discussed by comparing the resistances of different mesh densities,and the numerical calculation method was validated by comparing the simulation results with model test results.In addition,the different resistance components of the amphibious vehicle were analyzed based on the calculation results of the multiple molding.Then,the changes of resistance and sailing states of the amphibious vehicle model with openings were calculated and analyzed.The results show that,for the amphibious vehicle in transition stage,the proportion of wave-making resistance to the total resistance increases with the increase of velocity(the maximum rate can reach over 60%),the proportion of viscous pressure resistance to total resistance is 30%~40%,and the proportion of friction resistance to total resistance is less than 10%.The resistance increases when the amphibious vehicle added with openings,and the resistance increases by about 11%and the draft increases by about 5%when Fr_(▽)is 1.297.Compared with the amphibious vehicle model with non-openings,the amphibious vehicle model with openings shows changes in proportions of different resistance components to the total resistance:the proportion of wave-making resistance decreases and the proportion of viscosity-pressure resistance increases.