Numerical Simulation of Impact of Low Velocity Projectiles With Water Surface
الموضوعات : فصلنامه شبیه سازی و تحلیل تکنولوژی های نوین در مهندسی مکانیکنجمه خضرائیان 1 , ناصر دشتیان گرامی 2
1 - استادیار، گروه مهندسی مکانیک، دانشگاه آزاد اسلامی واحد اسلامشهر، تهران، ایران.
2 - دانشجوی دکتری، دانشکده مکانیک، دانشگاه تربیت مدرس، تهران، ایران
الکلمات المفتاحية: Fluid-Structure Interaction Water Impact ALE Formulation Finite Element Method,
ملخص المقالة :
In this article, Finite Element Method (FEM) and Eulerian-Lagrangies Algorithm (ELA) formulation were used to numerically simulate the impact of several low-velocity projectiles with water surface. Material models which were used to express behavior of air and water included Null material model. For the projectiles, rigid material model were applied. Results were validated by analyzing the impact of metallic cylinder with a water surface and then the impact of a wedge, sphere and special projectile at low-velocities were simulated. Major outputs were force and pressure applied to the projectile, variations of velocity and acceleration when entering to the water, stress-strain variations and variations of water surface in various steps of the analysis. Results showed that the impact of the structure with fluid can be modeled using finite element model with high accuracy in terms of quality and quantity.Numerical results obtained for cylinder well agrees with the available experimental data. Also the results for other projectiles show a logical trend
[1] Anghileri M., Spizzica A., Experimental validation of finite element models for water impacts, Proceedings of the second international crash users’ seminar, Cranfield Impact Centre Ltd, England, 1995.
[2] Korobkin A., Ohkusu M., Impact of two circular plates one of which is floating on a thin layer of liquid, Journal of Engineering Mathematics, vol. 50, 2004, pp.343–358.
[3] Wagner H., Phenomena associated with impacts and sliding on liquid surfaces, NACA Library, Langley Aeronautical Laboratory, 1936. Translation of: Wagner, H., 1932. U¨ ber stob und gleitvorga¨ nge an der oberfla¨ che von flu¨.
[4] Battistin D., Iafrati A., Hydrodynamic loads during water entry of two-dimensional and axisymmetric bodies. Journal of Fluids and Structure, vol. 17, 2003, pp.643–664.
[5] Park M., Jung Y., Park W., Numerical study of the impact force and ricochet behaviour of high speed water entry bodies. Computer Fluids, vol. 51, 2003, pp. 932-939.
[6] Roe SM., Numerical and experimental analysis of initial water impact of an air dropped REMUS AUV, Dissertation, MIT, 2005.
[7] Kleefsman T., Water Impact Loading on Offshore Structures. A Numerical Study, PHD thesis, 2005.
[8] Fairlie-Clarke AC., Tveitnes T., Momentum and gravity effects during the constant velocity water entry of wedge-shaped sections, Ocean Engineering, vol. 35, 2007, pp.706-716.
[9] Wu G., Numerical simulation for water entry of a wedge at varying speed by a high order boundary elementmethod,Journal of Marine Science and Application, vol. 11, 2012, pp. 143-149.
[10] Ahmadzadeh M., Saranjam B., Hoseini Fard A., Binesh AR., Numerical simulation of sphere water entry problem using Eulerian–Lagrangian method, Applied Matheatical Modelling, vol. 38, 2014, pp.1673-1684.
[11] Olovsson L., Souli M., ALE and Fluid Structure Interaction Capabilities in LS- DYNA, Proceedings of the 6th International LS-DYNA Users Conference”, Dearborn, Michigan, April, 2000.
[12] Randhawa H.S., Lankarani H. M., Finite element analysis of impacts on water and its application to helicopter water landing and occupant safety, International Journal of Crashworthiness, vol. 8, 2003, pp.189-200.
[13] Halliquist J.O., Simplified Arbitrary Lagrangian-Eulerian, LS-DYNA Theoretical Manual, 1998.
[14] LS-DYNA Theory Manual, Livermore Software Technology Corp, 2007.
[15] Seif M., Mousaviraad S., Saddathosseini S., Numerical Modeling of 2-d Water Impact in One Degree of Freedom, Sintesis Tecnologica, vol. 2, 2005, pp. 79-83.
[16] Greenhow M., Lin WM., Non linear free surface effects: experiments and theory. Report No. 83-19, Department of Ocean Engineering, MIT, Cambridge, 1983.
[17] Campbell IMC., Weynberg PA., Measurement of parameters affecting slamming. Report No 440, Wolfson Unit of Marine Technology, Tech. Rep. Centre No. OT-R-8042, Southampton, UK, 1980.
