【摘 要】
：
无限域中的波动方程数值模拟往往需要稳定有效的吸收边界来消除人为边界截断所引起的虚假反射.本文首先写出了全匹配层(PML)内SH波的波动方程推导结果,并给出了方程的Crank-N
论文部分内容阅读
无限域中的波动方程数值模拟往往需要稳定有效的吸收边界来消除人为边界截断所引起的虚假反射.本文首先写出了全匹配层(PML)内SH波的波动方程推导结果,并给出了方程的Crank-Nicolson计算格式与其中窄间导数2阶,6阶,10阶精度的有限差分算法以及伪谱法算法.然后设计了均匀各向同性介质模型和分层溶洞模型并引入图像处理中的信噪比(SNR)概念来定量研究边界吸收效果同PML宽度、不同精度算法的关系.数值结果表明当匹配层宽度比较薄时可以用低精度的有限差格式来获得比较好的吸收效果,当匹配层比较宽时,采用高精度的算法可以获得很好的吸收效果.最后对"反射系数"进行了讨论,指出"反射系数"的不足和文中用SNR来定量衡量吸收边界
其他文献
The clinical trials of tumor therapy using heavy ions beam 12C are now in progress at Institute of Modern Physics in Lanzhou. In order to achieve the precise ra
Fruit ripening is a complex process and is regulated by many factors.Ethylene and polygalacturonase (PG),lipoxygenase (LOX),expansin (EXP) are all critical regu
In order to calculate absolute efficiency of the BF3 detector, MCNP/4C code is applied to calculate rela-tive efficiency of the BF3 detector first, and then abs
In this paper,the structure and characteristics of the NS high-efficiency composite trays based on the doublelayer aperture jet sieve plate and compositely stru
Traditional texture region location methods with Gabor features are often limited in the selection of Gabor filters and fail to deal with the target which conta
In order to achieve a modulator with broad bandwidth and perfect impedance match,a novel electro-optical modulator based on GeO2-doped silica waveguides on sili
To analyze static pressure between back plate and cylinder in an A186 carding machine, a fluid model is established. The model takes into account static pressur
While the importance of tourist satisfaction has been recognized by academic researchers for at least four decades, adequate tourist satisfaction models have no
The vibrations of beams on a nonlinear elastic foundation were analyzed considering the effects of transverse shear deformation and the rotational inertia of be
Based upon a discussion on the merits and limitations of proportional navigation (PN) guidance law in which constant gravity compensation is included as a part,