Elasto-plastic time dependent impact analysis of high speed projectile on water surface

Authors

Malek Ashtar University of technology

Abstract

In this paper, elasto-plastic time dependent impact of high-speed projectile on water surface is simulated numerically using Arbitrary Lagrangian- Eulerian (ALE) method. The projectile is considered as elasto-plastic solid and its mesh is generated by Lagrangian approach. The water is also assumed as compressible fluid so its mesh is produced by Eulerian method. Three steps simulation are performed in this research; static, dynamic stress analysis and also impact analysis of full degrees of freedom (DOF) projectile on water surface using ALE method. The effects of fluid compressibility and cavitation are considered in last analysis. In order to validate results, the stress wave propagation produced in the projectile due to water impact is compared with exact ones. The results show that the maximum error compare with exact ones is 5%. Also the magnitude of maximum stress and location/path of fracture in the projectile are compared with experimental data. The good agreement between the predicted and analytical/experimental values shows the accuracy of this numerical algorithm. The impact of projectile on water surface is simulated with different angles. The results show that the safe zone of impact angle for present projectile is ±0.5°.

Keywords

Main Subjects


[1] Truscott TT, Epps BP, Belden J (2014) Water entry of projectiles. Annu Rev Fluid Mech 46: 355-378.
[2] Savchenko YN, Zverkhovskii AN (2009) Technique of conducting experiments on the high-velocity movement of inertial models in water in the supercavitation regime. Prikl Gidromekh 11(4): 69-75.
[3] Worthington AM, Cole RS (1897) Impact with a liquid surface, studied by the aid of instantaneous photography. Philos T Roy Soc A 189: 137-148.
[4] Bell GE (1924) On the impact of a solid sphere with a fluid surface. Philos Mag 48(287): 753-764.
[5] Birkhoff G, Caywood TE (1949) Fluid flow patterns. Appl Phys 20(7): 646-659.
[6] Birkhoff G, Isaacs R (1951) Transient cavities in air-water entry. Nav Ordnance Rep.
[7] Birkhoff G, Zarantonello EH (1957) Jets, wakes, and cavities. 1st edn. Academic Press, New York.
[8] May A, Woodhull JC (1948) Drag coefficients of steel spheres entering water vertically. Appl Phys 19:1109-1121.
[9] Abelson HI (1970) Pressure measurements in the water-entry cavity. Fluid Mech 44:129-144.
[10] May A (1975) Water entry and the cavity-running behavior of missiles. Tech rep, NAVSEA Hydroballistics Advisory Committee, Silver Spring, MD (Reproduced by NTIS).
[11] Savchenko YuN, Semenenko VN, Serebryakov VV (1993) Experimental  Research  of  Subsonic  Cavitating Flows.  DAN of Ukraine, 2:64-68. (in Russian.)
[12] Kirschner IN (2001) Results of selected experiments involving supercavitating flows. RTO AVT lecture series on supercavitating flows, Von Karman Institute, Brussels Belgium.
[13] Truscott TT, Beal DN, Techet AH (2009)  Shallow angle water entry of ballistic projectiles. Proc Cav Int Symp Cavitation, ed. S Ceccio, Art. 100.
[14] Afanas′eva SA, Belov NN, Burkin VV, D′yachkovskii AS, Evtyushkin EV (2013) Characteristic features of the high-velocity interaction of strikers with obstacles protected by a water layer. Izv Vyssh Uchebn Zaved Fizika 56(4): 8-15.
[15] Ishchenko AN (2014) Theoretical and experimental analysis of the high-velocity interaction of solid bodies in water. J Eng Phys Thermophys 87(2): 399-408.
[16] Karimi H, Mohammadi J, Arabi H, Fesanghari R, Farhadzadeh F, Shariati (2008) Design, production and experiment of small calliber supercavitating projectile. International Conference on innovative approaches to further increase speed of fast marine vehicles, moving above, under and in water surface, SuperFAST’2008, Russia.
[17] Ahmadzadeh M, Saranjam B, Hoseini Fard A, Binesh AR (2014) Numerical simulation of sphere water entry problem using Eulerian–Lagrangian method. Appl Math Model 38:1673-1684.
[18] ANSYS 15 Documentation (2009) User’s Manual. 
[19] Souli M, Benson DJ (2010) Arbitrary Lagrangian Eulerian and Fluid – structure Interaction. 1st edn. Wiley, Hoboken.
[20] Savchenko VT (1997) Reduction of overload on body entering water at high speed. AGARD FDP workshop.
[21] Hagedorn P, DasGupta A (2007) Vibrations and waves in continuous mechanical systems. John Wiley& Sons Ltd.