ACTA AERONAUTICAET ASTRONAUTICA SINICA >
Numerical simulation of high speed plate ditching
Received date: 2017-05-25
Revised date: 2017-07-04
Online published: 2017-07-04
Supported by
National Defense Pre-research Foundation; Funding of Jiangsu Innovation Program for Graduate Education (KYLX16_0392); A Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions
To have a deeper understanding of aircraft ditching, it is crucial to explore the hydrodynamics and mechanism of impact of water-entry objects. This paper numerically investigates the complex physical problems of high speed plate ditching using the finite volume method coupled with the Volume of Fluid (VOF) model. The Unsteady Reynolds-Averaged Navier-Stokes (URANS) equations and the Standard k-ε turbulence model are solved by the finite volume method. The VOF model is applied to capture the air-water interface. The relative motion between the plate and water is handled by the global dynamic mesh method. The high speed ditching of a 2D wedge-shaped body is studied, including the pressure distributions on lower surface of the plate and free surface deformations such as splash formation, movement and air cushion effects. The results show that there is obvious air cushion in the plate, with occurrence of regular air bubbles under the plate at 4° pitching angle, while no occurrence of air bubbles at 10° pitching angle. The water under the plate moves along the bottom of the plate, and the water speed increases dramatically at 10° pitching angle. The negative pressure zone appears significantly at large pitching angle.
LU Yujin , XIAO Tianhang , LI Zhengzhou . Numerical simulation of high speed plate ditching[J]. ACTA AERONAUTICAET ASTRONAUTICA SINICA, 2017 , 38(S1) : 721498 -721498 . DOI: 10.7527/S1000-6893.2017.721498
[1] KARMAN V T. The impact on seaplane floats during landing: NACA TN 321[R]. Washington, D.C.: National Advisory Committee for Aeronautics, 1929.
[2] WAGNER H. Phenomena associated with impacts and sliding on liquid surface[J]. Journal of Applied Mathematics and Mechanics, 1932, 12(4): 193-215 (in German).
[3] MAYO W L. Analysis and modification of theory for impact of seaplanes on water: NACA TR 810[R]. Washington, D.C.: National Advisory Committee for Aeronautics, 1945.
[4] LEIGH B R. Using the momentum method to estimate aircraft ditching loads[J]. Canadian Aeronautics and Space Journal, 1988, 34: 162-169.
[5] PENTECOTE N. Validation of the PAM-CRASH code for the simulation of the impact on water: DLR-IB 435.2003/3[R]. Stuttgart: Institute of Structures and Design, 2003.
[6] PENTECOTE N, VIGLIOTTI A. Crashworthiness of helicopters on water: Test and simulation of a full-scale WG30 impacting on water[J]. International Journal of Crashworthiness, 2003, 8(6): 559-572.
[7] SHOEMAKER J M. Tank tests of flat and v-bottom planning surfaces: NACA TN 509[R]. Washington, D. C.: National Advisory Committee for Aeronautics, 1934.
[8] MILWITZKY B. A generalized theoretical and experimental investigation of the motions and hydrodynamic loads experienced by v-bottom seaplanes during step-landing impacts: NACA TN 1516[R]. Washington, D.C.: National Advisory Committee for Aeronautics, 1948.
[9] MILWITZKY B. A generalized theoretical investigation of the hydrodynamic pitching moments experienced by v-bottom seaplanes during step-landing impacts and comparisons with experiment: NACA TN 1630[R]. Washington, D. C.: National Advisory Committee for Aeronautics, 1948.
[10] XU G D, DUAN W Y, WU G X. Numerical simulation of water entry of a cone in free-fall motion[J]. Quarterly Journal of Mechanics and Applied Mathematics, 2011, 64(3): 265-285.
[11] VIGNJEVIC R, MEO M. Simulation of helicopter under-floor structure impact on water[J]. International Journal of Crashworthiness, 2001, 6(3): 425-443.
[12] ORTIZ R, PORTEMONT G, CHARLES J L, et al. Assessment of explicit FE capabilities for full scale coupled fluid/structure aircraft ditching simulation[C]//International Council of the Aeronautical Sciences, 2002.
[13] XIAO T H, QIN N, LU Z Y, et al. Development of a smoothed particle hydrodynamics method and its application to aircraft ditching simulations[J]. Aerospace Science and Technology, 2017, 66: 28-43.
[14] WICK A T, ZINK G A, RUSZKOWSKI R A, et al. Computational simulation of an unmanned air vehicle impacting water[C]//45th AIAA Aerospace Sciences Meeting and Exhibit. Reston, VA: AIAA, 2007.
[15] QU Q L, HU M X, GUO H, et al. Study of ditching characteristics of transport aircraft by global moving mesh method[J]. Journal of Aircraft, 2015, 52(5): 1550-1558.
[16] IAFRATI A, SIEMANN M H, MONTAÉS L B. Experimental study of high speed plate ditching[C]//29th International Workshop on Water Waves and Floating Bodies, 2014.
[17] 陈震, 肖熙. 空气垫在平底结构入水砰击中作用的仿真分析[J]. 上海交通大学学报, 2005, 39(5): 670-673. CHEN Z, XIAO X. Simulation analysis on the role of air cushion in the slamming of a flat-bottom structure[J]. Journal of Shanghai Jiao Tong University, 2005, 39(5): 670-673 (in Chinese).
[18] SIEMANN M H, KOHLGRüBER D, MONTAÉS L B, et al. Numerical simulation and experimental validation of guided ditching tests[C]//11th World Congress on Computational Mechanics, 2014.
[19] HIRT C W, NICHOLS B D. Volume of fluid (VOF) method for the dynamics of free boundaries[J]. Journal of Computational Physics, 1981, 39(1): 201-225.
[20] ZHAO R, FALTINSEN O. Water entry of two-dimensional bodies[J]. Journal of Fluid Mechanics, 1993, 246: 593-612.
[21] ZHAO R, FALTINSEN O, AZRSNES J. Water entry of arbitrary two-dimensional sections with and without flow separation[C]//21st Symposium on Naval Hydrodynamics, 1996.
[22] MEI X M, LIU Y M, YUE D K P. On the water impact of general two-dimensional sections[J]. Applied Ocean Research, 1999, 21(1): 1-15.
[23] HOWISON S D, OCKENDON J R, WILSON S K. Incompressible water-entry problems at small deadrise angles[J]. Journal of Fluid Mechanics, 1991, 222: 215-230.
[24] OGER G, DORING M, ALESSANDRINI B, et al. Two-dimensional SPH simulations of wedge water entries[J]. Journal of Computational Physics, 2006, 213(2): 803-822.
/
| 〈 |
|
〉 |
CJA