Comparative Analysis of Arbitrary Lagrange in Eulerian (ALE) and Adaptive Smooth Particles Hydrodynamic (SPH) Simulation of Rocket Propelled Grenade (RPG) on Armors
Abstract
Military ground vehicles and helicopters are vulnerable to buried landmines, Improvised Explosive Devices (IED) and unguided ground launched threats particularly, the RPG-7 Rocket Propelled Grenade. Detonating IEDs and landmines creates a blast pressure and propagating blast waves near the ground vehicles causing both structural damage and crew injuries. On the other hand, projectiles and RPGs cause the structural damage and crew injuries by their impacting velocities. RPG-7 with a top speed of 294 meters per second (660 mph), strikes the target with a velocity in excess of 1100 meters per second (2460 miles per hour) with its jet tip speed and pierces up to 400 mm of Rolled Homogenous Armor (RHA) steel. There are numerous technologies available to mitigate both mine blast and impacting projectiles from RPGs. High penetration of RPGs with a shaped charge is a big problem to protect against and to simulate. End to end full system blast simulation methods and methodology are fully matured and used widely to protect military ground vehicles and soldiers, whereas full system simulation methods or methodology to capture the kinematics of RPG and its effects on a vehicle structure is not as robust as that of buried mine blast or IED. Arbitrary Lagrange in Eulerian (ALE) method is well suited for blast and ballistics simulation due to very large deformation of the structures and fragmentation. In this study, two simulation methods of RPG are compared, namely ALE and ALE coupled with adaptive Smooth Particle Hydrodynamics (SPH). Capturing the proper slug and jet formation is a numerical challenge in RPG simulation. In order to capture with high degree of accuracy, it is necessary to model the RPG threat with fine details. This will be computationally very expensive, especially when it comes to simulating full system which often requires a very large domain.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 11, 2019
- Accession Number
- AD1077018
Entities
People
- Madanmohan Vunnam
- Venkatesh Babu