Underwater blast loading of water-backed sandwich plates with elastic cores: Theoretical modelling and simulations

Abstract

Analytical predictions and finite element (FE) calculations are performed to predict the 1D response to underwater blast loading of sandwich plates with elastic cores, in contact with water on both sides and loaded by an exponentially decaying shock wave on one side. The theoretical models explicitly account for cavitation processes and effects of deep water, and their formulation helps identifying the governing parameters of the problem. Three characteristic regimes of behaviour are identified and regime maps are constructed. The analytical models are validated by FE simulations and used to explore the sensitivity of the predictions to the governing non-dimensional parameters. It is shown that, in the absence of plastic core deformation, sandwich plates with stiff cores are imparted higher blast impulses compared to those with softer cores and equivalent areal mass.

On the Development of New Test Techniques to Measure the Tensile Response of Materials at High and Ultra-high Strain Rates

“…The response of water was modelled by a Mie-Grüneisen equation of state, with a linear Hugoniot relation between applied pressure and volumetric strain; a tension cut-off was also modelled at pressure equal to the absolute zero, to model the effects of cavitation; a dynamic viscosity was also included. This modelling approach has been validated successfully in several studies on underwater explosions (for example [23][24][25]).…”

“…2, ensuring that the pressure in the water achieves rapidly an approximately uniform distribution is a key requirement for both tests. It is also important to avoid substantial cavitation in the pressurised chamber, as this would lead to complex fluid-structure interaction phenomena [23][24][25] which are hard to predict and would make interpretation of the test results difficult. In a preliminary study of the role of the geometry of the pressurised chamber, we found that these two objectives are achieved by: (i) maximising the ratio between crosssectional area of the piston and wetted area of the rubber sleeve (which also maximises the strain rate for a given impact velocity); (ii) maximising the ratio between diameter and height of the rubber sleeve; and (iii) avoiding very sharp corners in the pressurised chamber.…”

Energy Absorption Characteristics of Composite Material with Fiber–Foam Metal Sandwich Structure Subjected to Gas Explosion

“…In addition to researching foam metal as a barrier material, scholars have also increasingly focused their attention on multilayer sandwich structures [8][9][10][11][12][13][14][15][16][17]. Tarlochan, F. [18] discussed the use of sandwich structures in energy absorption applications and found that sandwich structures are a good choice for energy absorbers.…”

Numerical investigations on blast resistance of sandwich panels with multilayered graded hourglass lattice cores

“…Schiffer et al. [5] performed analytical predictions and finite element calculations to predict the one-dimensional (1D) response of sandwich panels with elastic cores under water blast loadings. Imbalzano et al.…”