The continuing development of multi-purpose finite element analysis (FEA) codes permits their application to provide new and penetrating insights into the difficult subject of underwater explosive effects and the coupled response of nearby structures. In this paper we investigate the use of one such code (DYNA2D) to model the physical processes associated with an underwater explosion. We compute models covering a range in explosive masses and depths of detonation. The models are shown to simulate much of the important physics of an underwater explosion including: explosive detonation, shock wave generation and transmission, bubble pulsation and the generation of bubble pulse pressure waves. The model results are compared to published experimental data for key features of an underwater explosion such as bubble periods, maximum bubble radii and characteristics of the shock and bubble pressure waves. The good quantitative agreement found for many of these features demonstrates that FEA codes can be used to model important aspects of an underwater explosion. Nevertheless a number of limitations are identified, the most serious of which is the absence of some important energy loss mechanisms associated with bubble collapse.

Hydronamics of Explosion presents the research results for the problems of underwater explosions and contains a detailed analysis of the structure and the parameters of the wave fields generated by explosions of cord and spiral charges, a description of the formation mechanisms for a wide range of cumulative flows at underwater explosions near the free surface, and the relevant mathematical models. Shock-wave transformation in bubbly liquids, shock-wave amplification due to collision and focusing, and the formation of bubble detonation waves in reactive bubbly liquids are studied in detail. Particular emphasis is placed on the investigation of wave processes in cavitating liquids, which incorporates the concepts of the strength of real liquids containing natural microinhomogeneities, the relaxation of tensile stress, and the cavitation fracture of a liquid as the inversion of its two-phase state under impulsive (explosive) loading. The problems are classed among essentially nonlinear processes that occur under shock loading of liquids and may be of interest to researchers in physical acoustics, mechanics of multiphase media, shock-wave processes in condensed media, explosive hydroacoustics, and cumulation.

Understanding the causes and effects of explosions is important to experts in a broad range of disciplines, including the military, industrial and environmental research, aeronautic engineering, and applied mathematics. Offering an introductory review of historic research, Shock Waves and Explosions brings analytic and computational methods

This book provides an elementary introduction to some one-dimensional fluid flow problems involving shock waves in air. The differential equations of fluid flow are approximated by finite difference equations and these in turn are numerically integrated in a stepwise manner. Artificial viscosity is introduced into the numerical calculations in order to deal with shocks. The presentation is restricted to the finite-difference approach to solve the coupled differential equations of fluid flow as distinct from finite-volume or finite-element methods. This text presents the results arising from the numerical solution using Mathcad programming. Both plane and spherical shock waves are discussed with particular emphasis on very strong explosive shocks in air. This text will appeal to students, researchers, and professionals in shock wave research and related fields. Students in particular will appreciate the benefits of numerical methods in fluid mechanics and the level of presentation.

The problem of external forces and problems involving the action of an explosion on a structure are investigated. These problems are of interest to engineers, designers, and scientific workers. The following 4 studies were made: 1. General Laws Governing the Propagation of Shock Waves, 2. Explosion in an Unbounded Medium, 3. Simplest Boundary Problems of Explosion Theory, and 4. Principal Aspects of the Problem of External Forces in the Case of Aerial and Underwater Explosions. (Author).