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The surface reflection pressure sensor installation flatness will directly lead to the change of the explosion shock wave pressure propagation and distribution law, affecting the test results accuracy, and the test data cannot accurately evaluate the ammunition explosion damage power. In this study, the numerical simulation model of the explosion shock wave pressure propagation and distribution law was established by using the explosive mechanics simulation software, and the pressure distribution law was studied when the sensors installation angles were 0°, 4°, 8°, 12°, −4°, −8°, and −12° respectively. Combined with analysis of the pressure peak value and the pressure evolution nephogram at different measuring points, it is clarified that the positive tilt angle of the sensor installation has an enhancing effect on the pressure peak, while the negative tilt angle has a attenuation effect on the pressure peak. Based on the calculation function formula of the surface reflected pressure peak value in the national defense engineering design code, the surface reflected pressure peak value correction function formula is established by introducing the sensor installation angle correction effect. This study results provide a theoretical basis for the design of ammunition explosion shock wave pressure engineering test scheme and the test data validity verification. [ABSTRACT FROM AUTHOR]

Ground reflection pressure plays a crucial role in evaluating the destructive power of ammunition explosions. Accurately measuring this pressure is essential for assessing ammunition's destructive capability and guiding ammunition design. In this study, a theoretical analysis of the parasitic effect of shock and vibration was conducted and COMSOL was employed for performing a multi-physics finite element numerical simulation analysis to elucidate the attenuation characteristics of stress waves in commonly used shock- and vibration-resistant materials. Furthermore, a device was designed using aluminum foam and polytetrafluoroethylene to mitigate the parasitic effects on the ground reflection pressure sensor. Experimental testing was conducted to validate the device's effectiveness. The results demonstrated that the device successfully reduced the intensity of stress waves reaching the ground reflection pressure sensor, with a relative attenuation rate of 29.6% in peak stress values. The sensor measurements obtained with the suppression device exhibited smoother curves and higher signal-to-noise ratios, significantly improving the reliability of the measurement results. Our study holds considerable engineering application value in enhancing the accuracy of shock wave pressure measurements in explosive fields. [ABSTRACT FROM AUTHOR]

• The paper uses a multi-channel high-precision data acquisition system to obtain the surface reflection pressure at different measurement points of the same TNT equivalent under three common surface propagation media (soil, sand, concrete) in the current shooting range, and compare the surface reflection pressure Through analysis, it is clear that the three kinds of surface propagation media hinder the propagation of shock wave pressure. • Based on the law of conservation of energy, analyze the energy conversion during the collision between the shock wave and the ground, and analyze the essential properties of the material to find that the energy conversion during the collision is mainly related to the density of the surface propagation medium and the shock wave velocity during the collision. • Propose the shock wave pressure impedance coefficient related to the material properties of the surface propagation medium, and use the method of dimensional analysis to determine the functional relationship between the impedance coefficient and the material properties. • Based on the surface reflection pressure calculation function relationship specified in the national defense code, the surface impedance coefficient is introduced to correct it, and the accuracy of the correction function relationship is verified by actual explosion shock wave data. The verification result shows: the established correction The calculation accuracy of the functional relation on the surface reflection pressure can reach 93.39%, which greatly improves the calculation accuracy of the existing surface reflection pressure function relation, and provides an effective calculation method for the calculation of shock wave pressure. Different propagation media have different effects on explosion shock wave attenuation during the propagation process. Studying the attenuation effect of dielectric impedance on shock wave pressure is of great significance to accurately measure shock wave pressure and evaluate the ammunition damage power. This study analyzes the measured shock wave overpressure peak data of TNT bare charge (60 kg) on soil, sand soil, and concrete grounds. Dimensional analysis was used to establish the medium impedance expressed by material density ρ , burst center distance r , equivalent TNT quality ω , and impedance coefficient η. Based on this, the mapping relationship between the propagation medium impedance coefficient η and the shock wave overpressure peak value was established. The test data were analyzed, and the results showed that in the same explosive environment, different ground propagation media had different impedance effects on the shock wave pressure, which is specifically expressed as η s o i l > η s a n d s o i l > η c o n c r e t e ; the modified calculation model of shock wave pressure established using material impedance coefficient has a fitting accuracy of 93.39% to the measured data, which can well represent the attenuation law between different ground propagation media and shock wave overpressure peak. This provides a theoretical basis and method for obtaining shock wave pressure data in explosion field and verifying validity of the test data. [ABSTRACT FROM AUTHOR]