Numerical Simulation of Impact of Low Velocity Projectiles With Water Surface

Subject Areas : Journal of Simulation and Analysis of Novel Technologies in Mechanical Engineering

نجمه  خضرائیان ¹ (استادیار، گروه مهندسی مکانیک، دانشگاه آزاد اسلامی واحد اسلامشهر، تهران، ایران.)
ناصر  دشتیان گرامی ² (دانشجوی دکتری، دانشکده مکانیک، دانشگاه تربیت مدرس، تهران، ایران)

Received: 2015-12-30 Accepted : 2015-12-30 Published : 2015-05-01

Keywords: Fluid-Structure Interaction Water Impact ALE Formulation Finite Element Method,

Abstract :

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

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