【作者】 贾虎；

【导师】 沈兆武；

【作者基本信息】 中国科学技术大学 ， 工程力学， 2011， 博士

【摘要】 随着军用和民用爆破技术的迅速发展，低能量导爆索的应用受到了广泛的重视。纤维爆炸索作为一种新型低能量导爆索，由金属外壳作为强约束，具有很强的侧向约束力，药芯密度高，装药均匀，线装药密度低，爆速稳定，质量有保证，同时金属外壳具有良好的防水性能。本文采用构建的水下爆炸试验塔和水下爆炸测试系统对纤维爆炸索水下爆炸特性进行了全面分析，揭示了其水下爆炸冲击波和气泡脉动运动规律，并对纤维爆炸索的水下应用进行了研究。将希尔伯特-黄变换引入到纤维爆炸索水下爆炸压力信号分析中，研究纤维爆炸索水下爆炸压力信号特征；采用水下爆炸光测系统研究纤维爆炸索水下爆炸气泡脉动规律；以水下爆炸理论为基础对纤维爆炸索水下爆炸水声特性进行研究，得到了有效连续的水声干扰源，有望为水下水声对抗提供新的手段；提出采用纤维爆炸索水下爆炸产生的气泡构成气泡帷幕进行水下爆炸能量衰减达到以“爆”制“爆”的目的，并研究了其衰减水中爆炸能量的效果；利用有限水域水下爆炸能量测试方法，对纤维爆炸索水下爆炸参数进行测量，获得了纤维爆炸索的能量分布情况，为推动纤维爆炸索的发展提供了基础性工作。本文具体研究内容如下：第一，在对目前水下爆炸压力信号分析中存在的问题进行分析的基础上，将希尔伯特-黄变换引入到水下爆炸压力信号分析中，并对其适用性进行评判；构建了水下爆炸测试装置，对纤维爆炸索和纤维爆炸索网栅结构的水下爆炸压力特性进行研究，发现纤维爆炸索冲击波压力在3μs从零上升到峰值压力5.21MPa，随后成指数近似衰减，在特征时间后衰减缓慢，冲击波压力信号能量主要集中在40KHz以下，尤以5KHz以下频带能量最高，能量主要集中在前80μs内；构建的纤维爆炸索网栅结构相当于水中爆炸冲击波发生器，可灵活选择布置方式以形成有规律的间断的多条冲击波压力；纤维爆炸索网栅结构水下爆炸压力信号频率主要集中在100KHz以下，尤以50KHz以下的最为明显，能量值较集中，波动能量集中在频率为100KHz范围以内，尤以50KHz以下的低频能量最大。第二，采用高速摄影对单根和两根纤维爆炸索水下爆炸气泡脉动规律进行了研究，获得纤维爆炸索水下爆炸的气泡脉动规律：单根纤维爆炸索第一次气泡脉动形状基本保持圆柱形，从第二次气泡脉动开始，气泡脉动的形状变为不规则圆柱形，首次气泡脉动周期为21.5ms，第二次脉动周期为15.5ms，气泡脉动最大半径为5.6cm；两根纤维爆炸索同时起爆后，首次气泡脉动周期为27.5ms，由于两个气泡相互抑制了对方气泡的运动，导致气泡的脉动周期增大；两根纤维爆炸索间距10cm布设，形成的两个气泡慢慢逐渐融合在一起，最后形成一近似规则的气泡帷幕，持续时间很长，能显著增加水下爆炸混响效应。第三，为了探求高功率、宽频带、连续性的水声干扰源，以水下爆炸理论为基础对纤维爆炸索水下爆炸水声特性进行研究，主要通过水下爆炸压力测试和气泡脉动实验，研究了纤维爆炸索水下爆炸的声压级、声持续时间、混响效应和功率谱特性，发现纤维爆炸索具有声压级高、频率范围广、混响效应强和声持续时间长的特点。提出的纤维爆炸索网栅结构水下爆炸产生多个水下爆炸脉冲，各脉冲信号能很好地衔接起来，使得爆炸声压级波形近似为一平稳、连续波，提高了其水下爆炸脉冲压力波的宽度，同时还产生气泡脉动和混响效应，显著增加了水下爆炸声的持续时间，可作为连续水下爆炸声源。第四，基于水下爆破工程防护安全的迫切需要，对提出的空气隔层衰减水下爆炸能量的设想进行了研究，发现空气隔层能有效衰减冲击波峰值压力，且衰减效果随空气隔层厚度增加有明显提高；空气隔层对水下爆炸冲击波各频率段的能量都有很好的衰减作用，对绝大部分频率段的冲击波能量衰减都在50%以上。第五，在借鉴国内外爆炸削能与安全防护措施与技术的基础上，利用纤维爆炸索水下爆炸产生气泡脉动的特性，构建纤维爆炸索网栅结构，通过纤维爆炸索网栅结构爆炸产生气泡帷幕，达到削减水下爆炸能量的作用，提出了爆炸气泡帷幕削能的新理念。爆炸气泡帷幕对冲击波峰值压力的衰减高达60%，对冲击波冲量的衰减高达62.2%；对冲击波能量的衰减效果十分明显，衰减效果高达57.7%；对各频段冲击波能量都有很好的衰减效果，特别是能有效消除高频成分。提出了爆炸气泡帷幕衰减水中冲击波能量的设置原则，以保证其能够达到最佳衰减效果。第六，对条形药包水下爆炸能量计算方法进行了分析，提出了纤维爆炸索水下爆炸能量计算方法，并对纤维爆炸索水下爆炸能量进行了测试，对其水下爆炸能量分布进行了系统研究，获得了能量分布的确切比例：冲击波能约占总能量的85%左右，气泡能占总能量的15%左右。纤维爆炸索总能量趋于一致，偏差不大，冲击波能量基本上在2.20MJ/kg上下。对纤维爆炸索的能量分布情况的研究，将推动纤维爆炸索的发展。更多还原

【Abstract】 With the rapid development of aviation, military and civil blasting technique, the development of low-energy detonating fuse has been widely appreciated. As a new low-energy detonating fuse, fiber detonating fuse has these characteristics: the metal shell as a strong constraint, with strong lateral binding; high density cored; uniform charged dynamite; density of linear charged dynamite is low and detonation occurs steadily with quality assurance; at the same time, the metal shell has a good waterproof performance. In this paper, the author has conducted a comprehensive analysis on the characteristics of underwater explosion with fiber detonating fuse by building an underwater explosion test tower and underwater explosion test system, which reveals its underwater explosion shock wave and the law of bubble pulsation. The author also has studied the application of fiber underwater detonating fuse explosion. In the test, the Hilbert - Huang transform was introduced to analyze the fiber fuse underwater explosion pressure signals and characteristics of the signals. Meanwhile, the underwater explosion optical fiber measurement system was used to explore the law of underwater explosion bubble pulsation. Also, based on the theory of underwater explosions, underwater explosion acoustic characteristics have been studied. And from the study an effective continuous source of acoustic interferencehas been found. The finding is expected to provide a new means of the underwater sound confrontation. The author has put forward that the attenuation produced through underwater explosion of the curtain constituted of fiber fuse underwater explosion bubbles can reach a critical system explosion in the end. Meantime, the explosion energy attenuation effect has been studied. In this paper, within limited water underwater energy test method for fiber fuse underwater explosion was used to measure the explosion parameters, to obtain the energy distribution of fiber fuse explosion, which provides a basis work for the development of fiber detonating fuse. The specific studies have been done as follows:First, based on the analysis of the current problems in the underwater explosion pressure signals, the Hilbert - Huang transform was introduced into the underwater explosion pressure signal analysis, and its applicability was evaluated. Through theunderwater explosive test device, the fiber fuse and fiber explosion explosive fusegrid structure of underwater explosion pressure characteristics have been studied, andthe findings like that the shock wave pressure in the fiber fuse explosion 3μs goesfrom zero to peak pressure 5.21MPa, followed by approximately exponential decay,in the characteristic time decay slowly, and the shock wave pressure signal energy ismainly concentrated in 40KHz, the highest energy is concentrated especially in thefollowing band energy 5KHz and within the first 80μs. The fiber fuse mesh structureis equal to an underwater explosion shock wave generator, the flexibility of which iseasy to select the layout way to form a number of discontinuous shock wave pressure.The signal frequency of the fiber fuse grid structure of the underwater explosionpressure is concentrated within 100KHz, and the signal is particularly obvious whenit is below 50KHz. That is to say, the energy value is much focused which isconcentrated within 100 KHz, and when it is lower than 50 KHz the low energyfrequency is maximum.Second, high-speed photography is used to study the law of explosion bubblesproduced by single or two fiber fuses underwater explosion. The findings is like this:single fiber fuse’s first time bubble pulsation remains cylinder-shape, but from thesecond bubble pulsation the shape becomes irregular cylinder; and the first bubblepulsation period is 21.5ms, the second pulsation period of 15.5ms; the maximumradius of bubble pulsation is 5.6cm. However, when two fiber explosion fusesdetonate at the same time, the first bubble pulsation period is 27.5ms, because the twobubbles each inhibit the movement of other bubbles, resulting in the increase ofbubble pulsation period. When the two fuses are laid with 10cm space, the bubblesgradually blend in and finally form a bubble curtain, the duration is very long, whichcan significantly increase the reverberation effect of underwater explosion.Third, to explore the high power, broadband, continuous interference sources ofwater sound, acoustic characteristics based on the theory of fiber fuse underwaterexplosion were studied. Primarily by stress testing and underwater explosion bubblepulsation experiment, the author has studied the fiber cable underwater explosionsound pressure level, sound duration, reverberation effects and characteristics of power spectral. It is found that fiber fuse is of high sound pressure level, of widerange of frequencies, of strong sound reverberation effect and of long duration. Basedon the findings, the author has proposed that the underwater explosion of fiber fusegrid can generate multiple underwater explosion pulses, each pulse can link up well tomake the blast wave a smooth, continuous one. Therefore, the width of underwaterexplosion pulse’s pressure wave is increased, and bubble pulsation and reverb effectsis also significantly increased, the duration of underwater explosions is increased, too,which can be used as a continuous sound source of underwater explosions.Fourth, to meet the urgent safety protection needs of underwater blasting, theauthor have studied the attenuation of the compartment air of underwater explosionenergy and found that compartment air can attenuate the peak shock wave pressureeffectively, and the effect of the attenuation can be significantly improved with theincrease of the interlayer air thickness; meantime, the air compartment can attenuatethe underwater explosion shock wave energy of each frequency band and theattenuation effect on most are above 50%.Fifth, drawing lessons from home and abroad in the security measures andtechnologies, based on the bubbles’characteristics of fiber fuse underwater explosion,building fiber fuse grid structure and making full use of the bubble curtain producedby the underwater explosion of the fiber fuse grid structure to reduce the underwaterexplosion energy, the author has proposed the new concept to attenuate explosionenergy through the explosion bubble curtain. Bubble curtain can attenuate the shockwave’s peak pressure up to 60%, and attenuate the shock wave impulse as high as62.2%; bubble curtain is also of great attenuation effect to the shock wave energy, upto 57.7%; and bubble curtain has a very good attenuation effect of each band of shockwave energy, in particular, can effectively eliminate the high frequency components.The author has set the principles in bubble curtain attenuating the water shock waveenergy to ensure its ability to achieve the best attenuation.Sixth, the author has analyzed the calculation method of Linear Chargeddynamite’s underwater explosion energy, offered calculation method of the fiber fuseunderwater explosion energy, tested the energy of fiber fuse underwater explosion,conducted the systematic research on the energy distribution of underwater explosion, and obtained the exact distribution of the total energy: shock wave energy is about 85%, the bubble is about 15% of total energy. The total energy of explosion fiber fuse conforms; the deviation is just a bit, and shock wave energy is basically about 2.20MJ/kg. The research on the distribution of the fiber fuse explosion energy will promote the development of fiber cable explosion.更多还原