Hydrodynamic Ram Analysis of Non-Exploding Projectile Impacting Water

2005 ◽  
Author(s):  
Flavio Poehlmann-Martins ◽  
Jon Gabrys ◽  
Mhamed Souli
Keyword(s):  
Fuel Tank ◽  
Steel Ball ◽  
High Rate ◽  
Pressure Waves ◽  
Water Tank ◽  
Fluid Structure ◽  
Element Size ◽  
Hydrodynamic Ram ◽  
Ram Analysis

Hydrodynamic pressures generated by a non-exploding projectile penetrating a fuel tank can be very destructive. Understanding the magnitude of the pressure and its distribution inside the tank is critical for designing structure to survive these incidents. This project uses LS-DYNA to simulate a hydrodynamic ram event created by a steel ball, traveling at a high rate, impacting a tank of water. Predicted pressures are then compared to measured pressures for validation. Additionally, modeling parameters such as element size and penalty factors for fluid structure coupling are investigated. Different ways to model reflections of pressure waves off the sidewalls are studied, as well. Good correlation is achieved for pressures at many locations inside the water tank.

A Coupling Method for Hydrodynamic Ram Analysis: Experimental and Numerical Investigation

2013 ◽  
Vol 136 (1) ◽  
Author(s):  
Souli Mhamed ◽  
Gabrys Jonathan
Keyword(s):  
Aerospace Industry ◽  
Fuel Tank ◽  
Coupling Method ◽  
Water Tank ◽  
Mesh Distortion ◽  
Fluid Structure ◽  
Hydrodynamic Ram ◽  
Coupling Parameters ◽  
Impact Problems ◽  
The Impact

Hydrodynamic pressures generated by a nonexploding projectile penetrating a fuel tank can be very destructive. During the impact, the projectile transfers momentum and kinetic energy to the container through the surrounding fluid. In aerospace industry, hydrodynamic ram effects are identified as an important factor for aircraft vulnerability because fuel tank of the aircraft is the most vulnerable component because the tank represents the largest exposed area to outside projectiles. Understanding the magnitude of the pressure and its distribution inside the tank is critical for designing the structure to survive these incidents. Numerical simulation when validated by tests data is an efficient tool to investigate mechanical phenomena of hydrodynamic ram effects and its damage on the surrounding structure. The main numerical difficulties that can be encountered in this kind of problems and in general penetration problems is the high mesh distortion of the fluid at the fluid–structure interface during projectile penetration. To prevent high mesh distortion of the fluid, a coupling method is used for the fluid as well as a new coupling algorithm is performed at the fluid–structure interface. The coupling method used in the paper has been developed with the collaboration of the first author in the ls-dyna code and validated for several applications in automotive and aerospace industry for fuel sloshing tank and bird impact problems. In this paper, experimental investigation has been performed and predicted pressure is compared with measured pressure for validation. In addition, modeling parameters such as element size and coupling parameters for the fluid structure coupling are investigated. The purpose of the research is to demonstrate the capability and potential of the fluid structure interaction for simulating this type of problems. Different ways to model reflections of pressure waves off the sidewalls are studied as well. Good correlation is achieved for pressure at specific location inside the water tank.

SIMULATION OF HYDRODYNAMIC RAM OF AIRCRAFT FUEL TANK BY BALLISTIC PENETRATION AND DETONATION

2008 ◽  
Vol 22 (09n11) ◽  
pp. 1525-1530 ◽  
Author(s):  
JONG H. KIM ◽  
SEUNG M. JUN
Keyword(s):  
Fluid Structure Interaction ◽  
Fuel Tank ◽  
Explicit Calculation ◽  
Fluid Structure ◽  
Structure Interaction ◽  
Intermediate Complexity ◽  
Hydrodynamic Ram ◽  
Aircraft Fuel ◽  
Ram Effect ◽  
Ballistic Penetration

Airframe survivability and hydrodynamic ram effect of aircraft are investigated. Penetration and internal detonation of a simple tank and ICW(Intermediate Complexity Wing) are simulated by nonlinear explicit calculation. Structural rupture and fluid burst are analytically realized using general coupling of FSI(Fluid-Structure Interaction) and adaptive master-slave contact. Besides, multi-material Eulerian solver and porosity algorithm are employed to model explosive inside fuel and tank bays which are defined in multi-coupling surfaces. Structure and fluid results are animated on the same viewport for enhanced visualization.

Developing an Advance Tire Hydroplaning Model Using Co-Simulation of Fully Coupled FEM and CFD Codes to Estimate Cornering Force

2018 ◽  
Author(s):  
Ashkan Nazari ◽  
Lu Chen ◽  
Francine Battaglia ◽  
Saied Taheri
Keyword(s):  
Cfd Model ◽  
Fluid Structure Interactions ◽  
Two Phase ◽  
Fluid Structure ◽  
The Public ◽  
Element Size ◽  
Road Surfaces ◽  
Computational Fluid Dynamics Cfd ◽  
Fully Coupled ◽  
Surrounding Fluid

Hydroplaning is a phenomenon which occurs when a layer of water between the tire contact patch and pavement pushes the tire upward. The tire detaches from the pavement, preventing it from providing sufficient forces and moments for the vehicle to respond to driver’s control inputs such as breaking, acceleration and steering. This work is mainly focused on the tire and its interaction with the pavement to address hydroplaning. Fluid Structure Interactions (FSI) between the tire-water-road surfaces are investigated through two approaches. In the first approach, the coupled Eulerian-Lagrangian (CEL) formulation was used. The drawback associated with the CEL method is the laminar assumption and that the behavior of the fluid at length scales smaller than the smallest element size is not captured. As a result, in the second approach, a new Computational Fluid Dynamics (CFD) Fluid Structure Interaction (FSI) model utilizing the shear-stress transport k-ω model and the two-phase flow of water and air, was developed that improves the predictions with real hydroplaning scenarios. Review of the public literature shows that although FEM and CFD computational platforms have been applied together to study tire hydroplaning, developing the tire-surrounding fluid flow CFD model using Star-CCM+ has not been done. This approach, which was developed during this research, is explained in details and the results of hydroplaning speed and cornering force from the FSI simulations are presented and validated using the data from literature.

Fluid-Structure Interaction With S-TRAC and KWUROHR Due to Pressure Waves

2003 ◽  
Author(s):  
Ulrich Neumann
Keyword(s):  
Fluid Structure Interaction ◽  
Dynamic Program ◽  
Pressure Waves ◽  
Structural Dynamic ◽  
Fluid Structure ◽  
Structure Interaction ◽  
Fluid Forces ◽  
Piping Systems

In the last years we have spent a lot of time to improve our programs and procedures, especially on the field of fluiddynamic investigations in piping systems. To get the best design of piping layout the results of fluiddynamic and structural calculations should be realistic as far as possible. In this connection a very important effect is the fluid-structure interaction (FSI) which we have implemented in S-TRAC in connection with our structural dynamic program KWUROHR. On the basis of different calculations we will show the influence of the coupling on the fluid forces and the piping layout.

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