SCALING THE ENERGY SPECTRA OF UNDERWATER EXPLOSION SHOCK WAVES

1963 ◽  
Author(s):  
Ermine A. Christian
2021 ◽  
Vol 62 (5) ◽  
pp. 97-105
Author(s):  
Thang Trong Dam ◽  
Viet Duc Tran ◽  

Shock waves, which derive from explosions, generate reflected and refracted waves when propagating in the layered medium with various acoustic stiffness. Depending on the acoustic characteristic of each layer of the medium, properties of reflected and refracted waves will increase or decrease pressures/stresses at the investigated point of medium, compared to influences of explosive shock waves (incident waves) propagated in a homogeneous and isotropic medium. Based on this mechanical physical property, scientists have studied a diversity of solutions decreasing effects of explosive shock waves in various medium such as rock and soil, water, air. However, currently there have not been any comprehensive theoretical studies on the reduction in intensity of the underwater explosion shock wave when interacting with bubble curtain. By using the analytical method and the virtual explosive method, the paper presents the propagation rule of new waves formed when the underwater explosion shock wave interacts with the bubble curtain. The results showed that the more the thickness of the bubble curtain or the higher the bubble content or the longer the distance from the explosive to the curtain, the weaker the intensity of the shock wave when passing through the curtain.


1998 ◽  
Vol 80 (18) ◽  
pp. 3911-3914 ◽  
Author(s):  
J. Bednarz ◽  
M. Ostrowski

2015 ◽  
Vol 20 (2) ◽  
pp. 49-54
Author(s):  
Iuliana Florina Pană ◽  
Luminiţa Cristina Alil ◽  
Florin Ilie

Abstract The main application of underwater detonation since the Second World War is to destroy military ships. Nowadays, a lot of studies are performed in order to discover a controlled and safe application of shock waves through different media. The paper presents the results of a research on a bubble curtain behaviour subjected to shock waves generated by an underwater TNT blast. The main objective was to analyze the mitigation solution of underwater explosion effects by means of gas bubbles. Simulations using ANSYS AUTODYN and explicit dynamics procedures were performed on a 3D model, in order to better understand the physical process of formation and propagation of a shock wave in the biphasic medium which represents the purpose of many researchers. The numerical simulations were performed taking into account the interaction between a shock wave and the bubble curtain considering a random distribution in space and bubble dimensions.


2017 ◽  
Vol 24 (s2) ◽  
pp. 111-117 ◽  
Author(s):  
Lu Lu ◽  
Degao Zou ◽  
Ye Zhu ◽  
Yun Dong

Abstract Shock waves arriving at a dam site are close to plane waves when the center of an underwater explosion is far from the dam site. In general, the wave pressure is calculated with COLE empirical formula. The COLE formula is a negative exponential function with respect to time. In this paper, a new analytical solution algorithm is proposed, which does not require the use of step-by-step time integration. In Comparison with the step-by-step time integration, the proposed algorithm requires relatively less calculation and avoids high-frequency oscillation. Furthermore, the vertical upstream surface and the sloping upstream surface in two types of the dams are analyzed in this paper. The research results indicate that the analytical solution can be applied for a dam with a vertical upstream surface. However, because the upstream face of a dam is inclined, the analytical solution can be obtained only for dams that are at lower height. Whenever the height of a dam is higher, then no analytical solution can be obtained, and only the use of step-by-step time integration can obtain a solution.


Sign in / Sign up

Export Citation Format

Share Document