To further enhance the wave-cutting efficiency of bubble curtain, a series of field tests were conducted. These tests involved the use of single-tube and multi-row bubble holes, as well as high-speed photography to observe the morphology of the bubble curtain. Additionally, a numerical calculation model for the equivalent thickness of the bubble curtain was constructed using AUTODYN software. The results indicate that the number of bubble hole rows is a critical factor affecting wave-cutting efficiency under the same air flow rate. At a detonation center distance of 12.0 m, the wave-cutting efficiencies for 1, 2, and 3 rows of holes are 89.92%, 97.25%, and 96.41%, respectively. At different distances from the detonation center, the two-row hole bubble curtain demonstrated the highest wave-cutting efficiency, consistently exceeding 95%. The thickness and density of the bubble curtain are maximized for two rows of holes, and the thickness of the bubble curtain is the key factor determining wave-cutting efficiency. The equivalent thickness fitting formula established by combining experiments and simulations has high reliability, and the numerical simulations also exhibit high accuracy. To achieve convenient, efficient and low-cost wave-cutting efficiency, it is recommended that the single-tube two-row hole bubble curtain is applied in similar projects.

To study the effect of aluminum powder particle size on the performance of CO₂ phase change explosion exciters, the changes in the thermal decomposition characteristics, safety, temperature resistance, and reaction heat were investigated by the calorimetric method(TG), ignition test, temperature resistance test, and reaction heat test. The results show that the thermal decomposition characteristics of the excitation agent did not change significantly after adding 40、80 and 120 μm aluminum powders. However, the apparent activation energy of the activator was significantly different. The apparent activation energy of the excitation agent containing 40 μm aluminum powder decreased by 52.92 kJ/mol. Still, the apparent activation energy of the excitation agent containing 80 μm and 120 μm aluminum powders increased by 55.21 and 57.53 kJ/mol, respectively. After adding different particle sizes of aluminum powder, each sample can be ignited in the air, and the combustion process is accompanied by white smoke. Among them, the excitation agent with 120μm aluminum powder burns more violently than that without aluminum powder and that with 40 and 80μm aluminum powder. The experimental results show that the excitation agents containing different particle sizes of aluminum powder can be excited by the electric primer, but the sample is not completely ignited. When these excitation agents are in a closed environment and under a certain pressure(greater than or equal to 0.2 MPa), they can be reliably ignited without an obvious explosion phenomenon, indicating that their safety is good. After holding at 70℃ for 48 h, the overall excitation agent added with aluminum powder did not change significantly, and the temperature index T_s was about 70℃, indicating that its temperature resistance was good. When the mass percentage of aluminum powder with different particle sizes is the same, the increase in reaction heat is about 12%, indicating that the particle size has little effect on the reaction heat of the excitation agents.

The shock wave generated by underwater explosions has a significant destructive impact on the surrounding environment. Therefore, it is crucial to implement bubble curtain protection for blast area safety. This study aims to investigate the influence of the number of bubble curtain layers on attenuating underwater explosion shock waves. An underwater explosion model with free water and varying numbers of bubble curtain layers was established using AUTODYN finite element software. Through experimental validation of the numerical model, a formula for calculating peak overpressure of the shock wave was derived, and the impact of different numbers of bubble curtain layers on shock wave attenuation in water was compared. The results demonstrate that employing a bubble curtain can effectively reduce peak overpressure from an underwater blast shock wave, achieving an attenuation ratio as high as 83%. Furthermore, increasing the number of bubble curtain layers can further enhance this attenuation effect, reaching more than 94% reduction in peak overpressure. Specifically, when comparing two-layered and one-layered bubble curtains at a distance of 12 m from the detonation center behind the bubble curtain, there is a reduction in peak overpressure by 61.94%. Similarly, using a three-layered bubble curtain leads to an additional decrease in peak overpressure at this distance by 11.38% compared to using a two-layered one. However, when utilizing four-layered curtains instead of three-layers ones, there is only a marginal decrease in peak overpressure(6.42%) at this same distance. In conclusion, implementing a bubble curtain significantly weakens shock waves within water bodies during explosive events. Moreover, fewer layers within the bubble curtain result in greater attenuation effects. However, diminishing returns are observed with each subsequent increase in layer count.