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291.
对比了6种不同弹种的国军标对冲击波测试的要求,总结了现有引线式和存储式冲击波测试方法的优缺点。重点介绍了一种小型无线冲击波测试系统,给出了系统的组成、工作原理及实验结果,实测数据表明该系统工作可靠、使用方便,符合国军标的相关要求。 相似文献
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用有限体积法求解三维完全气体的Navier-Stokes方程,并将通量守恒的分区计算方法和B-L湍流模型修正结合在一起,捕捉到了间断处的分离涡、激波、膨胀波等流场信息 相似文献
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针对海上漂浮软管波浪载荷计算,分析了软管在海上的形态和受力特点,建立了海上漂浮软管力学分析模型,指出直接运用现有Morison方程计算漂浮软管波浪载荷存在的不足,并根据基本原理提出了改进Morison方程。对海上软质管线处于一定海况,分别运用改进Morison方程与现有Morison方程计算海上波浪载荷,并运用ANSYS软件建立软管模型,结果表明现有Morison方程不适用于计算海上漂浮软管波浪载荷,载荷计算结果偏高约15%,从而验证了改进Morison方程的精确性,有利于准确分析波浪载荷对海上漂浮软管的作用情况。 相似文献
299.
《防务技术》2022,18(10):1895-1913
The cell-type continuous electromagnetic radiation system is a demonstration device capable of generating high-power millimeter electromagnetic waves of a specific wavelength and observing their effects on living organisms. It irradiates a biological sample placed in a 30 × 30 × 50 cm3 cell with electromagnetic waves in the 3.15-mm-wavelength region (with an output of ≥1 W) and analyzes the temperature change of the sample. A vacuum electronic device-based coupled-cavity backward-wave oscillator converts the electron energy of the electron beam into radiofrequency (RF) energy and radiates it to the target through an antenna, increasing the temperature through the absorption of RF energy in the skin. The system causes pain and ultimately reduces combat power. A cell-type continuous electromagnetic radiation system consisting of four parts—an electromagnetic-wave generator, a high-voltage power supply, a test cell, and a system controller—generates an RF signal of ≥1 W in a continuous waveform at a 95-GHz center frequency, as well as a chemical solution with a dielectric constant similar to that of the skin of a living organism. An increase of 5 °C lasting approximately 10 s was confirmed through an experiment. 相似文献
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All underwater drilling and blasting operations generate seismic waves.However,due to a lack of suitable vibration sensing instruments,most studies on the propagation of seismic waves have been limited to shorelines near construction areas or wharfs,whereas comparatively few studies have been conducted on the larger seafloor itself.To address this gap,a seafloor vibration sensor system was developed and applied in this study that consists of an autonomous acquisition storage terminal,soft-ware platform,and hole-plugging device that was designed to record the blasting vibration intensities received through submarine rocks at a given measurement point.Additionally,dimensional analyses were used to derive a predictive equation for the strength of blast vibrations that considered the in-fluence of the water depth.By combining reliable vibration data obtained using the sensor system in submarine rock and the developed predictive equation,it was determined that the water depth was an important factor influencing the measured vibration strength.The results using the newly derived equation were compared to those determined using the Sadowski equation,which is commonly used on land,and it was found that predictions using the derived equation were closer to the experimental values with an average error of less than 10%,representing a significant improvement.Based on these results,the developed sensor system and preliminary theoretical basis was deemed suitable for studying the propagation behavior of submarine seismic waves generated by underwater drilling and blasting operations. 相似文献