短脉冲激光支持爆轰波参数分析

发布时间：2018-08-13 19:12

【摘要】：随着激光理论的发展,衍生出了激光与材料相互作用物理学为基础理论支撑的一系列学科。由于激光作用到靶材的时候会使得靶材表面产生一系列的物理化学变化,进而使得靶材材料的性质发生改变,甚至使得靶材材料发生一系列的毁伤。在这一系列的变化过程中,首先是材料升温熔融、然后气化形成等离子体,等离子体继续吸收激光能量形成激光支持爆轰波。所以这一系列的变化都与激光支持爆轰波有间接或直接的关系,因此研究激光支持爆轰波和分析激光参数对它的影响是不可或缺的。本论文中使用ns激光脉冲照射铝板,陈述了从激光支持爆轰波起爆到激光支持爆轰波形成的整个过程,并且在这个过程中还仔细说明了物质对激光的吸收过程。分析了激光支持爆轰波的基本理论,然后构建了短脉冲激光支持爆轰波参数分析的理论模型,通过这个模型推演得到等离子体的控制方程。针对整个激光支持爆轰波的形成过程,论文中使用C-J模型对等离子体初始状态进行了分析,确定了起爆阶段的等离子体的一系列参数。然后根据等离子体的膨胀过程,搭建出激光支持爆轰波的二维流场模型,得到等离子体控制方程之后,使用时空守恒元解元方法对等离子体的控制方程进行数值计算,得到等离子体温度、压强、速度及密度等随时间、空间变化的情况。本文使用了MATLAB进行结果仿真,通过仿真分析得到了一系列激光参数与激光支持爆轰波之间的关系,为了更好地利用激光支持爆轰波力学毁伤的效果,除了提高激光功率密度以外,还需要针对不同的目标材料,对激光脉宽、脉冲间隔进行合理的设计。比较相同功率密度条件下的单脉冲ns激光和多脉冲ns激光入射情况,得到多脉冲情况下靶面冲量累计较大、产生的力学损伤效果会较明显,最佳脉冲间隔与脉冲宽度、光强大小、目标材料等因素有关。
[Abstract]:With the development of laser theory, a series of disciplines supported by laser-material interaction physics have been derived. When laser acts on the target, a series of physical and chemical changes will occur on the surface of the target, which will change the properties of the target material and even cause a series of damage to the target material. In this series of changes, first the material is heated and melted, then the plasma is vaporized, and the plasma continues to absorb laser energy to form laser-supported detonation waves. Therefore, this series of changes are indirectly or directly related to the laser-supported detonation wave, so it is indispensable to study the laser-supported detonation wave and to analyze the influence of laser parameters on it. In this paper, we use ns laser pulse to irradiate aluminum plate, describe the whole process from laser supported detonation wave initiation to laser supported detonation wave formation, and explain the laser absorption process of matter in this process. The basic theory of laser-supported detonation wave is analyzed, and then a theoretical model for parameter analysis of short-pulse laser-supported detonation wave is constructed, through which the governing equation of plasma is derived. For the whole laser-supported detonation wave formation process, the C-J model is used to analyze the initial state of the plasma, and a series of parameters of the plasma during the initiation stage are determined. Then according to the process of plasma expansion, a two-dimensional flow field model of laser supporting detonation wave is built. After the plasma control equation is obtained, the time-space conservation element solution element method is used to numerically calculate the plasma control equation. The variation of plasma temperature, pressure, velocity and density with time and space are obtained. In this paper, MATLAB is used to simulate the results, and the relationship between a series of laser parameters and laser-supported detonation wave is obtained through simulation analysis. In order to make better use of laser to support the mechanical damage of detonation wave, Besides increasing laser power density, the laser pulse width and pulse interval should be reasonably designed for different target materials. Comparing the incidence of monopulse ns laser and multi-pulse ns laser at the same power density, the cumulative impulse of target surface is larger under the condition of multi-pulse, and the mechanical damage effect is obvious, the optimum pulse interval and pulse width are obtained. Light intensity, target material and other factors.
【学位授予单位】：电子科技大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：TN249

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