An instrument design of a high-pressure optical cell system for in situ detection of aqueous samples was reported, including a manual pump, a pressure multiplier, and a high-pressure cell. The cell with three optical windows can be used within a pressure range of up to 600 MPa, using water as the pressure transmitting medium. When JGS1 quartz windows were employed, the safe pressure was around 300 MPa. The hermetic sealing effect of quartz was so good that the pressure was hold very well during experiments. In order to demonstrate the functioning of the system, the fluorescence spectra of tryptophane was determined at different pressures.

To investigate the large penetrated hole's performance of shaped charge against multi-layer target, a titanium alloy liner of shaped charge is proposed. Using the method of experimental and numerical simulation, the jet formation and penetration into multi-layer target are investigated. Difference among the explosion energy conversion, jet tip velocity, jet length, penetration performance, and also the shock wave propagation in the penetrating process are analyzed, for which liner materials include titanium alloy, mild steel and Cu. It is found that compared with the mild steel or Cu liner, the liner material made of titanium alloy has a larger energy of jet whose shape is podgier, the depth as well as diameter of crater is bigger. Although the penetration depth decreases slightly, the size of crater formed in concrete increases obviously and the average penetrated hole diameter on multi-layer increases by 20%.

In order to probe into the damage mode and its mechanisms, a box-like beam was designed, and numerical analysis and experimental verification were carried out. In the discussions, how vertical bending load forms was investigated, and the properties of flow-field were analyzed in details when explosion bubble oscillates, how explosion parameters affect the dynamics of beams was attained, and the basic condition for beam sagging damage was initially proposed. The results show that there exists a low-pressure zone like a “concave” in the fluid between beam and explosion bubble when the bubble contracts in the near-field, and the low-pressure field causes the sagging damage. If the parameter of λ, the ratio of stand-off to maximum bubble radius, meets 1<λ<2.5, explosion bubble will possibly cause beams damage into sagging condition. The smaller the value of parameter λ, the greater the impact damage.

Experiment and simulation of cylindrical charge underwater explosion bubble motion has been conducted to investigate the collapse mechanism of non-spherical bubble and the behavior of its jet. The experimental results were compared against the numerical results for different configurations of charge. Results show that jet generated by a non-spherical bubble behaves different from that of a spherical bubble, which could be attributed to the variance of radius of curvature on the bubble interface. The collapse time for an initial bubble surface with bigger radius of curvature is earlier than that with smaller radius of curvature. As a result, the water jet may exhibit an asymmetric form.

We studied an optional/dual-mode warhead with an ejectable cross-shaped cutting reseau fixed at a proper place before the liner to realize multi-function of ammunition based on 60 mm arc-cone liner Explosive Formed Projectile (EFP) charge configuration. The optional/dual-mode warhead can change the kill elements mode according to the target properties (heavily or lightly armored targets), and can form single EFP or MEFP (Multiple Explosively Formed Projectile) to provide the most effective attack. The whole process of formation, flying and penetration of single EFP and MEFP was simulated using LS-DYNA3D. The simulation results are in good agreement with the experimental data. This study indicates that the single EFP has a good aerodynamic stability at a velocity of 1 508 m/s and it can penetrate through the 45 steel targets with a thickness of 30 mm; While the MEFP has a velocity between 1 500 and 1 750 m/s with an even distribution and can penetrate through the 45 steel targets with a thickness of 6 mm. The obtained results provide important reference to the design of dual-mode warhead.

Based on parallel computation of explosive blasting in concrete and analysis of the numerical result as well as study on the foundational theory of explosion mechanics, a conclusion has been drawn that in the process of explosive blasting in rocks, explosive energy is released by way of shock waves' several times reciprocate reflect in blast cavity which is full of explosion product while rock mediums are damaged and moved, and the interface loses gradually its positive expansion velocity along with the rarefaction wave in blast cavity.

In order to study the damage effect of ship structure subjected to jet impacting, characteristic of jet loading was investigated theoretically and numerically. A jet impact-model was verified based on a ship cabin model underwater explosion test. An analysis was made by combining the calculation results and test data. Results show that the jet impact can induce a strong local response on the structure. Under certain circumstance, jet impacting response is more severe than that caused by shock wave even when bubble incepts at a relatively far position. Therefore, jet impact problem cannot be considered only in proximal underwater explosion test. The jet impact-model developed in this work could reflect the loading feature accurately, and would provide reference to underwater explosion experimental analysis.

Foaming polyethylene (EPE) and foamed polypropylene (EPP) were tested in drop-weight experiments to study the dynamic mechanical behavior of polymeric foams. With the proposal of a method to obtain stress-strain curve under certain strain rate, constitutive model of EPE was established in Low Density Foam. Comparison was made between real experiment and simulation results and the accuracy was validated. Based on the constitutive model, energy absorption and protective performance of polymeric foam was evaluated in refrigerator package drop experiments.

Based on the experimental data of an underwater target bombed by underwater explosion, the energy was studied by means of monitoring interior acceleration signals and wavelet packet analysis with high resolvability and localization. By using the monitored signals, the time-frequency distributions and the energy distributions in blasting frequency bands were obtained. Considering the close relation between energy distribution for different frequency bands and the damaged target effect, the peak acceleration, the energy on dominant frequency bands and natural frequency bands of interior device were taken into account as discrimination factors. A discrimination model was proposed and the re-substitution method was used to verify the stability of model. The results show that the predicted results are consistent with actual values, and prove that the choice of bands energy as an damage index is reasonable.

In order to research the effects of different grounds on the shock wave propagation and the general laws of the bubble motion of underwater explosion from a bottom charge, principle experiments of underwater explosion were conducted in a water tank. Several physical phenomena observed such as bubble jetting and bubble migration from the different grounds were discussed. It is suggested that the shape and dynamic behavior of bubble have great dependence on the ground properties. Furthermore, underwater explosion from a bottom charge usually causes serious damage to the bottom, and the reflected wave is sometimes stronger than the incident shock wave such as for the rock ground.

The particle velocity of the rubber composite armor and the mechanism of the armor interfering with the shaped charge jet were studied by analyzing the wave propagation rules in the armor. The fracture model of shaped charge jet affected by the rubber composite armor was put forward based on the jet fracture model in the air. The effect of the armor thickness on the jet fracture was also analyzed. The theoretical conclusion was proved by the X-ray and DOP (Depth of Penetration) experiments of Ø56 mm standard shaped charge jet penetrating the rubber composite armor with difference rubber thickness at the angle of 68°. The results show that the rubber composite armor can disturb the shaped charge jet effectively and the protection capability reduces with the increasing of the natural rubber thickness while the thickness satisfied the structure effect.

It is feasible to develop a shield with high strength fiber materials in order to protect spacecraft against space debris's impacts. Basalt fiber is one of the high strength materials being noticed in recent years. The aim of this study was to probe into the macro-damage property on perforation and mecro-damage of fibers in basalt fiber woven fabric. The molten materials caused by high temperature under impact were observed. The perforation equation of the fabric was developed based on the hypervelocity impact data. The mecro-damage reasons of the basalt fiber were researched according to the damage form of the cross section on the fiber. This study is beneficial to the application of basalt fiber woven fabric to the space debris shielding.

After exiting the muzzle, the projectile continues being accelerated to maximum velocity by the propellant flow. The increasing of velocity in post-effect period has a great influence in the design of weapons and weapon firing precision. The process of firing under different conditions was numerically studied using finite volume method based on moving grids. Force on the projectile and the movement of the projectile were discussed. When and where the projectile reach its maximum velocity as well as the velocity increasing rate and the factors influences it was analyzed in detail. The result shows that the rate of increasing velocity may be over 3%, and is hardly affected by bullet mass and explosive charge.

Parameters of high speed object are often measured by multi-channel velocity interferometer system for any reflector (VISAR) or electric probe technology. In order to validate experimental results, and analyze test system factors affecting measurement precision, the free-surface velocity history of metal flyer driven by detonation was measured by multi-channel VISAR and electric probes. The displacement-time curve of metal flyer was calculated from the measured velocity-time curve, and then contrasted with the results measured by electric probes. Experimental results show that all v-t curves measured by multi-channel VISAR are coincident well within the maximum difference of 1.45%. And the maximum difference of time at 5, 10, 15 mm standoff measured by VISAR and electric probe is respectively 0.02, 0.02, 0.07 μs after modified. The difference between two sets of system at the same position increases with the movement distance of flyer, it could be resulted from the increased waveform difference of the explosive lens with the flight distance of flyer.

The booster of explosive which has large mass and can produce high detonation pressure was used in the underwater explosion experiments to accurately measuring the energy of TBL, a kind of inertia high energy explosive based on TATB. The result shows that the energy of booster from the underwater explosion experiment is consist with the theoretical result. TBL contains 70% of TNT energy. The energy of shock waves attenuates faster with the increase of explosion pressure.

Explosive configuration of PBX-1 was impacted by dual rail sled loading target, PVDF and quartz gauges were used to test the incident and reacted pressure in explosive. Intuitionistic image and detail of impact between target and configuration were recorded by digital and frame cameras. The curves of overpressure produced by explosive reaction are tested by blast overpressure gauges, and relative release rate of energy is estimated. The results indicate primarily that explosive occurs partial blast and the relative release rate of energy is about 51.8% when the incident pressure is 0.48 GPa.

Abrasive water jet is widely used in water resources and architectural engineering, oil and gas engineering and marine resources development. It is significant to study the erosion characteristics of the jet and material destruction mechanisms to improve the efficiency of water jet. Using the self-developed device, the experiments were performed on abrasive water jet erosion characteristics formed by three types of nozzles including self-oscillating cavitation nozzle, Venturi nozzle, and cone-shaped nozzle under confining pressure. Destruction mechanisms of metal material were also analyzed. The results show that the erosion efficiencies of the self-oscillating cavitation nozzle and Venturi nozzle are higher than that of the cone-shaped nozzle; cavitation erosion can help improve the efficiency of abrasive water jet. Abrasive water jet erosion efficiency decreases with the confining pressure increasing, mainly due to the confining pressure inhibiting pressure pulse, cavitation effect, and impinging pressure. The mechanism of materials by cavitating abrasive water jet includes three roles of impact erosion, cavitation and their synergism.

The activity of polyphenol oxidase from red raspberry treated at 600 MPa for 45 min is even up to 40%, indicating strong pressure resistance. In order to further inactivate polyphenol oxidase from red raspberry, the combination effect of high hydrostatic pressure and metal ions on polyphenol oxidase activity was investigated. The change of polyphenol oxidase activity treated at 400 and 600 MPa after adding metal ions was revealed. The activity of raspberry polyphenol oxidase gradually decreases with the pressure increasing and/or the holding time extending with/without adding metal ions. Fe²⁺, Mn²⁺ (both inhibited polyphenol oxidase) and Cu²⁺ (activated polyphenol oxidase) in combination with pressure have synergistic effects, Ca²⁺ (inhibited polyphenol oxidase) combined with pressure has antagonistic effect, and Zn²⁺ (not change polyphenol oxidase activity) has no synergistic/antagonistic effect.