楔形体入水冲击中的壁面效应分析
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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.
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
[1]DOBROVOLSKAYA Z N.On some problems of similarity flow of fluid with a free surface[J].Journal of Fluid Mechanics,1969,36:805-829.
[2]ZHAO R,FALTINSEN O.Water entry of twodimensional bodies[J].Journal of Fluid Mechanics,1993,246:593-612.
[3]TASSIN A,JACQUES N,EL MALKI ALAOUI A,et al.Assessment and comparison of several analytical models of water impact[J].The International Journal of Multiphysics,2010,4(2):125-140.
[4]YU P Y,REN H L,LI H,et al.Slamming study of wedge and bow-flared sections[J].Journal of Ship Mechanics,2016,20(9):1109-1120.
[5]SUN H,FALTINSEN O M.Water impact of horizontal circular cylinders and cylindrical shells[J].Applied Ocean Research,2006,28(5):299-311.
[6]杨强,林壮,郭志群,等.穿浪双体船艏部分段模型入水砰击的数值仿真[J].华中科技大学学报:自然科学版,2015,43(6):42-47.
[7]IRANMANESH A,PASSANDIDEH-FARD M.Athree-dimensional numerical approach on water entry of a horizontal circular cylinder using the volume of fluid technique[J].Ocean Engineering,2017,130:557-566.
[8]BILANDI R N,JAMEI S,ROSHAN F,et al.Numerical simulation of vertical water impact of asymmetric wedges by using a finite volume method combined with a volume-of-fluid technique[J].Ocean Engineering,2018,160:119-131.
[9]CHALLA R,YIM S C,IDICHANDY V G,et al.Rigidobject water-entry impact dynamics:finite-element/smoothed particle hydrodynamics modeling and experimental validation[J].Journal of Offshore Mechanics and Arctic Engineering,2010,136(3):031102.
[10]YANG Q,QIU W.Numerical solution of 3-D water entry problems with a constrained interpolation profile method[J].Journal of Offshore Mechanics and Arctic Engineering,2012,134(4):041101.
[11]YANG Q,QIU W.Numerical simulation of water impact for 2D and 3D bodies[J].Ocean Engineering,2012,43:82-89.
[12]陈震,肖熙.二维楔形体入水砰击仿真研究[J].上海交通大学学报,2007,41(9):1425-1428.
[13]曹正林,吴卫国,空气层对高速三体船连接桥砰击压力峰值影响二维仿真研究[J].船舶力学,2008,12(2):237-242.
[14]YU P,LI H,ONG M C.Numerical study on the water entry of curved wedges[J].Ships and Offshore Structures,2018,13(8):885-898.
[15]KOROBKIN A.Shallow-water impact problems[J].Journal of Engineering Mathematics,1999,35(1/2):233-250.
[16]ERMANYUKA E V,OHKUSU M.Impact of a disk on shallow water[J].Journal of Fluids and Structures,2005,20:345-357.
[17]吴家鸣,龚国围,朱良生.平底结构砰击作用下限制水域的流体动力特性[J].华南理工大学学报:自然科学版,2008,36(10):97-101.
[18]IAFRATI A,BATTISTIN D.Hydrodynamics of water entry in presence of flow separation from chines[C]//Proc of 8th International Conference on Numerical Ship Hydrodynamics.Busan:Society of Naval Architects of Korea,2003:22-25.
[19]TASSIN A,KOROBKIN A A,COOKER M J.On analytical models of vertical water entry of a symmetric body with separation and cavity initiation[J].Applied Ocean Research,2014,48:33-41.
[2]ZHAO R,FALTINSEN O.Water entry of twodimensional bodies[J].Journal of Fluid Mechanics,1993,246:593-612.
[3]TASSIN A,JACQUES N,EL MALKI ALAOUI A,et al.Assessment and comparison of several analytical models of water impact[J].The International Journal of Multiphysics,2010,4(2):125-140.
[4]YU P Y,REN H L,LI H,et al.Slamming study of wedge and bow-flared sections[J].Journal of Ship Mechanics,2016,20(9):1109-1120.
[5]SUN H,FALTINSEN O M.Water impact of horizontal circular cylinders and cylindrical shells[J].Applied Ocean Research,2006,28(5):299-311.
[6]杨强,林壮,郭志群,等.穿浪双体船艏部分段模型入水砰击的数值仿真[J].华中科技大学学报:自然科学版,2015,43(6):42-47.
[7]IRANMANESH A,PASSANDIDEH-FARD M.Athree-dimensional numerical approach on water entry of a horizontal circular cylinder using the volume of fluid technique[J].Ocean Engineering,2017,130:557-566.
[8]BILANDI R N,JAMEI S,ROSHAN F,et al.Numerical simulation of vertical water impact of asymmetric wedges by using a finite volume method combined with a volume-of-fluid technique[J].Ocean Engineering,2018,160:119-131.
[9]CHALLA R,YIM S C,IDICHANDY V G,et al.Rigidobject water-entry impact dynamics:finite-element/smoothed particle hydrodynamics modeling and experimental validation[J].Journal of Offshore Mechanics and Arctic Engineering,2010,136(3):031102.
[10]YANG Q,QIU W.Numerical solution of 3-D water entry problems with a constrained interpolation profile method[J].Journal of Offshore Mechanics and Arctic Engineering,2012,134(4):041101.
[11]YANG Q,QIU W.Numerical simulation of water impact for 2D and 3D bodies[J].Ocean Engineering,2012,43:82-89.
[12]陈震,肖熙.二维楔形体入水砰击仿真研究[J].上海交通大学学报,2007,41(9):1425-1428.
[13]曹正林,吴卫国,空气层对高速三体船连接桥砰击压力峰值影响二维仿真研究[J].船舶力学,2008,12(2):237-242.
[14]YU P,LI H,ONG M C.Numerical study on the water entry of curved wedges[J].Ships and Offshore Structures,2018,13(8):885-898.
[15]KOROBKIN A.Shallow-water impact problems[J].Journal of Engineering Mathematics,1999,35(1/2):233-250.
[16]ERMANYUKA E V,OHKUSU M.Impact of a disk on shallow water[J].Journal of Fluids and Structures,2005,20:345-357.
[17]吴家鸣,龚国围,朱良生.平底结构砰击作用下限制水域的流体动力特性[J].华南理工大学学报:自然科学版,2008,36(10):97-101.
[18]IAFRATI A,BATTISTIN D.Hydrodynamics of water entry in presence of flow separation from chines[C]//Proc of 8th International Conference on Numerical Ship Hydrodynamics.Busan:Society of Naval Architects of Korea,2003:22-25.
[19]TASSIN A,KOROBKIN A A,COOKER M J.On analytical models of vertical water entry of a symmetric body with separation and cavity initiation[J].Applied Ocean Research,2014,48:33-41.