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在现代工程技术中,应力波的传播有着十分重大的意义,因为它提供了在不透明材料中无损检测缺陷和非均匀性的主要方法;并提供了研究在与冲击和爆炸有关的动态载荷条件下材料响应的唯一方法。象核反应堆安全、集成电路检测及装甲侵彻等各种技术的进展,强烈地取决于模拟应力波传播和改进表征材料动态响应特性等方面的进展.在包括油藏勘探、地震监测以及预测因地震和爆炸载荷而产生的地壳运动等岩土工程和地球物理学应用的广阔范围里,应力波起着主要的作用.固体中应为波的固有复杂性(即三个波速、各向异性及非均匀性),以及涉及强载荷应用中重要的非线性,使得模拟应力波现象方面的进展,决定性地取决于大规模的计算.日益增多的超巨型计算机,为模拟包括象各向异性、非均匀性、缺陷、非线性和滑移界面等复杂性质的三维现象,提供了取得进展的优越机会.为了进行这些计算,为了获得声学映象(这需要逆问题的算法.在这些间题中,缺陷的尺寸和形状,以及密度和弹性模量的变化,都是用超声波探测所关心的区域而得到的),必须研究精确而有效的算法。为了可靠地测定所需的几何特征和材料特性,改进超声源和接收器的性能表示法是不可或缺的.对材料的动态非弹性响应作进一步了解,是实现所形成的计算能力的全部好处的关键.应变率敏?
In modern engineering, the propagation of stress waves is of great importance because it provides the primary means of nondestructive detection of imperfections and inhomogeneities in opaque materials; and provides a study of the effects of dynamic stress on shock and explosions The only way the material responds. Progress in various technologies, such as nuclear reactor safety, integrated circuit testing and armor penetration, strongly depends on advances in simulated stress wave propagation and improved characterization of the material’s dynamic response etc. In areas including reservoir exploration, seismic monitoring and prediction of earthquakes And crustal movement caused by explosive loads, stress waves play a major role in the wide range of geotechnical and geophysical applications of solids such as the inherent complexity of waves (ie, the three wave velocities, the anisotropy and the non- Uniformity) and important non-linearities involved in high-load applications make the progress in simulating stress wave phenomena decisively dependent on large-scale computations.An increasing number of supercomputer computers have been used to simulate anisotropic, non-uniform The three-dimensional phenomena of complex nature such as sexuality, defects, nonlinearity, and slippage interfaces provide excellent opportunities for making progress.In order to obtain acoustic maps for these calculations (which requires an inverse problem algorithm, in these questions, defects The size and shape, as well as the changes in density and elastic modulus, are all obtained by means of sonar scanning of the area of interest), it is necessary to study precisely Efficient algorithms. In order to reliably determine the desired geometry and material properties, it is essential to improve the performance representation of the ultrasound source and receiver, and further understanding of the dynamic inelastic response of the material is the full benefit of the resulting computational capability The key is strain rate sensitivity?