头部喷气影响航行体入水载荷的数值模拟
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摘要
针对航行体穿越自由液面入水过程,开展了不同喷气流量及入水初始速度下头部喷气对入水流场演化及冲击载荷影响的动态数值模拟研究。结果表明:头部喷气可有效减小入水最大冲击载荷,推迟冲击峰值出现时间,并在其头部形成较为稳定的附着气泡,改善水动力外形,而侧面形成的空泡则可减小摩擦阻力,从而增加航行体水下运动速度;随着喷气量的增加,以上作用愈加显著。入水初始速度增加时,航行体头部会形成明显的空气垫,减缓冲击载荷增大的趋势;相同喷气量下降载效果随着入水速度的增加而先增大,而后基本不变。
The influence of head-jetting on the flow field and the impact of water-entry with different jet mass flow rate and initial velocity of object is numerically investigated. The results show that the head-jetting could reduce and delay the impact peak significantly. Meanwhile the bobble in front of the object head could improve the hydrodynamic shape effectively, while the air attached to the side wall could reduce the friction. As a result, the velocity of the object in the water is increased.These benefits are enhanced with the increase of the jet mass flow rate. The air cushion effect is observed for a high-speed water-entry object, which could weaken the impact loading. Additionally,the performance of the jet on reducing the impact increases with the velocity of water-entry firstly and then keeps mostly unchangeable.
The influence of head-jetting on the flow field and the impact of water-entry with different jet mass flow rate and initial velocity of object is numerically investigated. The results show that the head-jetting could reduce and delay the impact peak significantly. Meanwhile the bobble in front of the object head could improve the hydrodynamic shape effectively, while the air attached to the side wall could reduce the friction. As a result, the velocity of the object in the water is increased.These benefits are enhanced with the increase of the jet mass flow rate. The air cushion effect is observed for a high-speed water-entry object, which could weaken the impact loading. Additionally,the performance of the jet on reducing the impact increases with the velocity of water-entry firstly and then keeps mostly unchangeable.
引文
[1] Von Karman T. The Impact on Seaplan, Floats during Landing[J]. Technical Report Archive&Image Library,1929, 321:1-9
[2] Sharov Y F. Slamming Stresses in Ship Bottom Plates[J].Sudostroenie. 1958, 24(4):5-9
[3] Meyetioff W K. Die Berechnung Hydro-elastischer Stbsse[J]. Sehiffstechnik. 1965, 12:18-30 and 49-64
[4] Pukhnachov V V. Linear Approximation in the Problem on a Blunt Body Entry in Water[J]. Din Sploslnoi Sredy,1979, 38:143-150
[5] Chuang S L. Experiments on Flat-bottom Slamming[J].Journal of Ship Research. 1966,10:10-17
[6] Chuang S L. Investigation of Impact of Rigid and Elastic Bodies with Water[R]. Structural Analysis, 1970:1-97
[7] Wu G X, Sun H, He Y S. Numerical Simulation and Experimeital Study of Water Entry of a Wedge in Free Fall Motion[J]. Journal of Fluids and Structures, 2004, 19:277-289
[8]陈小平,祁恩荣,王辉.三维锥形体入水砰击的仿真研究[C]//中国造船工程学会船舶力学学术委员会成立三十周年暨学委会全体会议,2010CHEN Xiaoping, QI Enrong, WANG Hui. The Simulation Study on Water Entry of 3-Dimension Cone-Shaped Bodies[C]//China Shipbuilding Engineering Society of Ship Mechanics Thirty Anniversary of the Establishment of Academic Committee and Plenary Session, 2010
[9]路龙龙.空投鱼雷入水技术研究[D].西安:西北工业大学,2006LU Longlong. Research on Theory and Application of Torpwdo's Water Entry[D]. Xi'an:Northwestern Polytechnical University, 2006
[10]魏照宇,石秀华,王银涛,等.水下航行器高速斜入水冲击的探索仿真研究[J].西北工业大学学报,2010, 28(5):718-722WEI Zhaoyu, SHI Xiuhua, WANG Yintao, et al. Exploring High-Speed Oblique Water Entey Impact of an Underwater Vehicle[J]. Journal of Northwestern Polytechnical University. 2010, 28(5):718-722
[11]石汉成,蒋培,程锦房.头部形状对水雷入水载荷及水下弹道影响的数值仿真分析[J].舰船科学技术,2010, 32(10):104-107SHI Hancheng, JIANG Pei, CHENG Jinfang. Research on Numerical Simulation of Mine Water-entry Impact Acceleration and Underwater Ballistic Trajectory under the Different Mine's Head Shape[J]. Ship Science and Tech-nology, 2010, 32(10):718-722
[12]王军.鱼雷入水冲击动力学仿真研究[D].昆明:昆明理工大学,2010WANG Jun. The Impact Dynamics Simulation Study of Torpedo Water-entry[D]. Kunming:Kunming University of Science and Technology, 2010
[13]潘龙,王焕然,姚尔人,等.头部喷气平头圆柱体人水缓冲机制研究[J].工程热物理学报,2015, 36(8):1691-1695PAN Long, WANG Huanran, YAO Er, et al. Mechanism Research on the Water-entry Impact of the Head-jetting Flat Cylinder[J]. Journal of Engineering Thermophysics,2015, 36(8):1691-1695
[14]姜晨醒.湍流减阻添加剂对超空化流动的影响机理研究[D].哈尔滨工业大学,2015JIANG Chenxing. Study on the Mechanism of the Supercavitating Flow Influenced by Turubulent Drag-reducing Additives[D]. Harbin Institute of Technology, 2015
[15]王焕然,王新兵,窝丁日海,等.半球头圆柱体穿越气液界面的数值模拟[J].工程热物理学报,2013, 34(10):1856-1859WANG Huanran, WANG Xinbing, WODING Rihai, et al. Numerical Simulation of Hemisphere-cylinder Body Crossing the Gas-liquid Interface[D]. Journal of Engineering Thermophysics, 2013, 34(10):1856-1859
[2] Sharov Y F. Slamming Stresses in Ship Bottom Plates[J].Sudostroenie. 1958, 24(4):5-9
[3] Meyetioff W K. Die Berechnung Hydro-elastischer Stbsse[J]. Sehiffstechnik. 1965, 12:18-30 and 49-64
[4] Pukhnachov V V. Linear Approximation in the Problem on a Blunt Body Entry in Water[J]. Din Sploslnoi Sredy,1979, 38:143-150
[5] Chuang S L. Experiments on Flat-bottom Slamming[J].Journal of Ship Research. 1966,10:10-17
[6] Chuang S L. Investigation of Impact of Rigid and Elastic Bodies with Water[R]. Structural Analysis, 1970:1-97
[7] Wu G X, Sun H, He Y S. Numerical Simulation and Experimeital Study of Water Entry of a Wedge in Free Fall Motion[J]. Journal of Fluids and Structures, 2004, 19:277-289
[8]陈小平,祁恩荣,王辉.三维锥形体入水砰击的仿真研究[C]//中国造船工程学会船舶力学学术委员会成立三十周年暨学委会全体会议,2010CHEN Xiaoping, QI Enrong, WANG Hui. The Simulation Study on Water Entry of 3-Dimension Cone-Shaped Bodies[C]//China Shipbuilding Engineering Society of Ship Mechanics Thirty Anniversary of the Establishment of Academic Committee and Plenary Session, 2010
[9]路龙龙.空投鱼雷入水技术研究[D].西安:西北工业大学,2006LU Longlong. Research on Theory and Application of Torpwdo's Water Entry[D]. Xi'an:Northwestern Polytechnical University, 2006
[10]魏照宇,石秀华,王银涛,等.水下航行器高速斜入水冲击的探索仿真研究[J].西北工业大学学报,2010, 28(5):718-722WEI Zhaoyu, SHI Xiuhua, WANG Yintao, et al. Exploring High-Speed Oblique Water Entey Impact of an Underwater Vehicle[J]. Journal of Northwestern Polytechnical University. 2010, 28(5):718-722
[11]石汉成,蒋培,程锦房.头部形状对水雷入水载荷及水下弹道影响的数值仿真分析[J].舰船科学技术,2010, 32(10):104-107SHI Hancheng, JIANG Pei, CHENG Jinfang. Research on Numerical Simulation of Mine Water-entry Impact Acceleration and Underwater Ballistic Trajectory under the Different Mine's Head Shape[J]. Ship Science and Tech-nology, 2010, 32(10):718-722
[12]王军.鱼雷入水冲击动力学仿真研究[D].昆明:昆明理工大学,2010WANG Jun. The Impact Dynamics Simulation Study of Torpedo Water-entry[D]. Kunming:Kunming University of Science and Technology, 2010
[13]潘龙,王焕然,姚尔人,等.头部喷气平头圆柱体人水缓冲机制研究[J].工程热物理学报,2015, 36(8):1691-1695PAN Long, WANG Huanran, YAO Er, et al. Mechanism Research on the Water-entry Impact of the Head-jetting Flat Cylinder[J]. Journal of Engineering Thermophysics,2015, 36(8):1691-1695
[14]姜晨醒.湍流减阻添加剂对超空化流动的影响机理研究[D].哈尔滨工业大学,2015JIANG Chenxing. Study on the Mechanism of the Supercavitating Flow Influenced by Turubulent Drag-reducing Additives[D]. Harbin Institute of Technology, 2015
[15]王焕然,王新兵,窝丁日海,等.半球头圆柱体穿越气液界面的数值模拟[J].工程热物理学报,2013, 34(10):1856-1859WANG Huanran, WANG Xinbing, WODING Rihai, et al. Numerical Simulation of Hemisphere-cylinder Body Crossing the Gas-liquid Interface[D]. Journal of Engineering Thermophysics, 2013, 34(10):1856-1859