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Several aluminum-based explosives are prepared and their underwater explosion performances, including the specific bubble energy and specific shock wave energy, are measured in underwater explosion experiments. The formulation characteristics of the explosives involve the aluminum/oxygen (Al/O) ratio, aluminum particle size, and the total content of all solid components, including ammonium perchlorate (AP), aluminum (Al), and cyclotrimethylenetrinitramine (RDX). The results indicate that the Al/O ratio of the explosives produces a great effect on the specific shock wave energy and specific bubble energy of the explosives. The total specific energy of the explosive reaches the maximum value at Al/O = 0.44. It is notable that an increase in the total solid content (AP, Al, and RDX) in the explosive formulation can effectively increase the specific total energy of the explosives. When the total solid content is increased by 2% (by weight) in the explosive formulation, the total energy of the explosive can be increased by about 0.1 times the TNT equivalent. Moreover, the particle size of the aluminum powder can also significantly affect the energy of the explosives. The smaller particle size of the aluminum powder is beneficial to the energy release of aluminum and can increase the total explosion energy.

In this paper, a modified smoothed particle hydrodynamics (SPH) formula is deduced to solve the problem of interfaces with a high density ratio. Simplified SPH models for single and double cylindrical shells (abbreviated as single-hull and double-hull models, respectively) are established to study shock wave propagation and to conduct the damage analysis. The SPH results for the single-hull model are verified by AUTODYN. In addition, the damage analysis indicates that the single-hull model is damaged more severely than the double-hull model. The inner shell in the double-hull model is protected by a water interlayer.

To study underwater explosions, a new type of an underwater pressure sensor using polyvinylidene fluoride as a sensing element is developed and well calibrated. The sensor is then applied in underwater explosion tests of RDX explosives with addition of aluminum in the fiber or powder form. The results show that the peak pressure of shock waves slightly decreases when aluminum is added to RDX, and the peak pressure of the fiber aluminum composite explosive is slightly inferior to that of the explosive containing the aluminum powder at the same measuring positions.

A new aluminized explosive is proposed, and the approach is to replace the aluminum powder in the traditional aluminized explosive with an aluminum film. The purpose is not only to improve mechanical properties and lower the impact sensitivity of traditional aluminized explosives, but also to reduce environmental pollution in the aluminum particle production process. The pressure-time curves of the aluminum film explosive and RDX are measured in underwater explosion experiments. The peak pressure, impulse, shock wave energy, and bubble energy are obtained by analyzing the curves. The results of the study indicate that the peak pressure of the aluminum film explosive is lower than that of RDX. However, the aluminum film explosive maintains a high pressure for a longer period of time. The large amount of energy is found to liberate by subsequent reactions of the Al film with the primary detonation products. The increase in the explosion energy of the aluminum film explosive is based mainly on the increase in the bubble energy.

A series of experiments is performed to compare underwater shock wave attenuation of a new insensitive and aluminized high explosive RS with TNT, JH14, and PBXN-111 explosives. A new model with a uniform expression is proposed to characterize the pressure-time histories of the explosives. Numerical results show that the new model is applicable for both aluminized explosives and ideal explosives. The correlation coefficients for fitted curves are verified by thousands of test data for different explosives, and the accuracy is above 0.99. The energy of the underwater shock wave generated by PBXN-111 and TNT characterized by the new model agrees well with available experimental results. In addition, the shock energy of the new insensitive and aluminized high explosive RS is higher than that of PBXN-11 by 13.4%. The general performance of underwater shock wave attenuation of the insensitive and aluminized high explosive RS is found to be better than that of TNT, JH14, and PBXN-111 explosives.

Hydrodynamics of a deep underwater explosion is considered. The magnetic field generated by this explosion in a quasistatic approximation taking into account the induction effect is calculated. The effect of self-induction on the magnetic field is analyzed quantitatively.

Results of a study of hydroacoustic, acoustic, and seismic effects from a series of three large-scale chemical explosions of 0.5, 2, and 5 tons, conducted in November, 1999 in the Dead Sea, are presented. The shots were detonated at a water depth of 70 m (485 m below the ocean level). The main objective of the experiment was calibration of seismic stations of the International Monitoring System in the Middle East, using accurate travel times and source phenomenology features of underwater explosions. The largest shot provided magnitude about 4 and was recorded at distances up to 3500 km. Near-source seismic and hydroacoustic observations obtained were utilized to estimate source parameters of the conducted explosions. Based on the curve-fit equation of the time-pressure measurements, the direct shock wave energy was estimated as 30.8% of the total explosive energy. The TNT equivalent to the 5000 kg charge of the explosive used (Chenamon) was determined as 4010 kg, corresponding to the manufacturer’s estimate of the Chenamon energy as ≈80% TNT.

Results of a full‐scale study of hydroacoustic, seismic, and acoustic effects of an underwater explosion of charges of a chemical high explosive are described. The study had a comprehensive character and included video filming of surface phenomena at the explosion epicenter, registration of hydroacoustic waves in water, seismic waves on the ground, and acoustic waves in air at distances of 0.08–30 km from the explosion epicenter. Parameters of these waves and the character of their decay with distance were obtained, and the wave spectra were analyzed. It is shown that the main specific feature of the wave shapes of hydroacoustic, seismic, and acoustic signals is caused by oscillations of the cavity filled by detonation products, which can be used to identify underwater explosions.

Measurement techniques and some results obtained in underwater, above‐water, and underground nuclear explosions at the north test site are described. Parameters of hydroacoustic signals in a nuclear explosion in the Chernaya bay and in coastal underground nuclear explosions are described.

The series of dimensionless parameters for the generalized representation of the space–time parameters of underwater explosions is supplemented taking into account the influence of density and velocity of sound in the liquid on shock‐wave propagation.

The efficiency of using an air-water drop curtain for protection from the force and noise action of an air shock wave generated by an open explosion is studied experimentally. It is shown that the curtain generated by outburst of sprayed water after an advanced underwater explosion of a demolition cord is a reliable means of pressure decrease at the shock-wave front. The dependence of the “effective coefficient of charge-mass reduction” on the position of the curtain relative to the point of explosion, its length, time of evolution, and other conditions was studied. Zones with local pressure increase or decrease in the shock wave were found, which is explained by imposition of secondary compression and expansion waves on the shock wave. Possible physical mechanisms that ensure the protective effect are considered.

The formation of a plume by the underwater explosion of a toroidal-shaped charge is interesting to study because the gas bubble formed as a result of the explosion assumes the shape of a torus during its evolution. The present paper is devoted to a further investigation of the plume due to the explosion of a toroidal charge. The characteristic horizontal size of the plume, the problem concerning the motion of the free surface of the liquid, the conditions for which the maximum uplift of liquid into the plane of symmetry assumes an apriori value, and the motion of the plume in the vertical direction are all studied.

This paper is devoted to an investigation of the nature of shock passage through the interlayers consisting of materials with different dynamic stiffness, to determine of the initial shock amplitude and the law of its attenuation in the near zone (at ranges less than 10 discharge radii). The explosion and shock generation were recorded by a schlieren shadowgraph and high-speed photorecorder SFR-1 in 2 modes: frame by frame scan and continuous sweep. The investigations performed permitted establishment of the possibility, in principle, of controlling the shock parameters during an underwater explosion in the zone near the charge.