The ground penetrating radar(GPR) forward simulation all aims at the singular and regular models, such as sandwich model, round cavity, square cavity, and so on, which are comparably simple. But as to the forward of c...The ground penetrating radar(GPR) forward simulation all aims at the singular and regular models, such as sandwich model, round cavity, square cavity, and so on, which are comparably simple. But as to the forward of curl interface underground or “v” figure complex model, it is difficult to realize. So it is important to forward the complex geoelectricity model. This paper takes two Maxwell’s vorticity equations as departure point, makes use of the principles of Yee’s space grid model theory and the basic principle finite difference time domain method, and deduces a GPR forward system of equation of two dimensional spaces. The Mur super absorbed boundary condition is adopted to solve the super strong reflection on the interceptive boundary when there is the forward simulation. And a self-made program is used to process forward simulation to two typical geoelectricity model.展开更多
提出了一种基于三角面元数据生成涂层目标时域有限差分(finite-difference time domain,FDTD)共形网格的方法。通过将原目标中各三角面元的顶点沿曲面在该点处的法线方向内移(内涂层)或外移(外涂层)所需的厚度,得到一组关于涂层的三角...提出了一种基于三角面元数据生成涂层目标时域有限差分(finite-difference time domain,FDTD)共形网格的方法。通过将原目标中各三角面元的顶点沿曲面在该点处的法线方向内移(内涂层)或外移(外涂层)所需的厚度,得到一组关于涂层的三角面元数据。其中曲面上各顶点处的法线方向近似等于包围该顶点的各三角面元的单位法向的矢量和。对于局部涂敷的情况,可根据需要只将涂敷部分所包含的三角面元顶点进行相应的移动,而其余顶点的位置保持不变。利用投影求交法,由原目标的三角面元数据和新生成的涂层三角面元数据即可得到共形FDTD计算所需要的共形网格参数。数值结果验证了方法的正确性和有效性。展开更多
文摘The ground penetrating radar(GPR) forward simulation all aims at the singular and regular models, such as sandwich model, round cavity, square cavity, and so on, which are comparably simple. But as to the forward of curl interface underground or “v” figure complex model, it is difficult to realize. So it is important to forward the complex geoelectricity model. This paper takes two Maxwell’s vorticity equations as departure point, makes use of the principles of Yee’s space grid model theory and the basic principle finite difference time domain method, and deduces a GPR forward system of equation of two dimensional spaces. The Mur super absorbed boundary condition is adopted to solve the super strong reflection on the interceptive boundary when there is the forward simulation. And a self-made program is used to process forward simulation to two typical geoelectricity model.
基金Project supported by China Postdoctoral Science Foundation (20100481488), Key Fund Project of Advanced Research of the Weapon Equipment (9140A33040512JB3401).
文摘提出了一种基于三角面元数据生成涂层目标时域有限差分(finite-difference time domain,FDTD)共形网格的方法。通过将原目标中各三角面元的顶点沿曲面在该点处的法线方向内移(内涂层)或外移(外涂层)所需的厚度,得到一组关于涂层的三角面元数据。其中曲面上各顶点处的法线方向近似等于包围该顶点的各三角面元的单位法向的矢量和。对于局部涂敷的情况,可根据需要只将涂敷部分所包含的三角面元顶点进行相应的移动,而其余顶点的位置保持不变。利用投影求交法,由原目标的三角面元数据和新生成的涂层三角面元数据即可得到共形FDTD计算所需要的共形网格参数。数值结果验证了方法的正确性和有效性。