摘要
为了分析楔形体入水冲击中壁面的影响,采用有限体积法和重叠网格技术建立了楔形体在有限流域入水冲击下的数值模型.通过不同网格密度和时间步长下冲击载荷的比较,论证了数值模型的收敛性.通过与文献结果的对比,验证了数值模型的正确性.利用已验证的数值模型,分析了流域宽度和深度对冲击载荷的影响.将有限流域和无限流域入水冲击载荷的无因次比值定义为壁面效应,进而分析了冲击速度和底升角对壁面效应的影响.结果表明:深度和宽度方向的壁面效应会增大楔形体的入水冲击载荷,冲击速度对壁面效应影响较小,底升角越小的楔形体,深度方向的壁面效应越明显.
In order to analyze the effect of the wall during the water entry of a wedge,a numerical model for simulating the water entry of a wedge in a finite fluid domain was established by using the finite volume method and overlapping mesh technique.The convergence of the numerical model was discussed by comparing the impact loads with different mesh densities and time steps.The numerical model was verified by comparing with published results.Based on the validated numerical model,the effects of the width and depth of the fluid domain on impact loads were analyzed.The dimensionless ratio of the impact loads during the water entries in finite fluid domain and infinite fluid domain was defined as wall effect,and then the influence of impact velocity and bottom rise angle on the wall effect was analyzed.The results show that the wall effect in depth and width directions will increase the impact loads acting on the wedge;the impact velocity has little influence on the wall effect;the wall effect in the depth direction will become more obvious for the wedge with a smaller deadrise angle.
引文
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