A Simplified Method to Assess the Damage of a Deeply Immersed Cylinder Subjected to Underwater Explosion

A Simplified Method to Assess the Damage of a Deeply Immersed Cylinder Subjected to Underwater Explosion

Kevin Brochard Herve Le Sourne Guillaume Barras

GeM Institute, UMR 6183 CNRS, ICAM Nantes, France.

Direction Générale de l’Armement – Techniques Navales, Toulon, France.

Page: 
95-108
|
DOI: 
https://doi.org/10.2495/SAFE-V9-N2-95-108
Received: 
N/A
|
Accepted: 
N/A
|
Published: 
30 June 2019
| Citation

OPEN ACCESS

Abstract: 

The presented work is focused on the development of a simplified analytical method to study the struc- tural response of a deeply immersed cylinder submitted to the primary shock wave of an underwater explosion. It relies on a methodology developed by hoo Fatt and Wierzbicki where the two dimensional boundary value problem for a cylindrical shell is converted to an equivalent one-dimensional problem of a plastic string on a non-linear plastic foundation. unstiffened cylinders immersed in shallow water have already been investigated by the authors, taking into account fluid structure interaction effects. The aim of the proposed work is to adapt the formulations to a deep immersed cylinder. The analytical developments will be presented for unstiffened cylinders. The resulting plastic dents are compared to experimental and numerical results. Although some limitations are pointed out, it is shown that this method is promising and may be advantageously used to assess rapidly the damage of a deep immersed cylinder submitted to an underwater explosions.

Keywords: 

fluid structure interaction, immersed cylinder, rigid-plastic analysis, Underwater explosion.

  References

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