Numerical Simulation Of Explosive Source With Different Excitation Parameters

By using the software ANSYS/LS-DYNA, we adopted Lagrange algorithm based on the finite element method to simulate the seismic source of the cylindrical explosive. This article focuses on the influence of different excitation parameters after source excitation in limestone and soil. In this paper we focuses on the excitation of explosive in single well, and at first we determine the range of the plastic zone and then study the influence of different parameters on relative excitation energy. Then, we study the effect of different excitation parameters on frequency component of excited seismic waves. The medium velocity from 1000m/s to 5500m/s, we study the influence of different rock properties on source excitation effect. We discuss about the perspective of rock properties of limestone and soil and four groups of parameters including the explosive velocity, dose, filling state and drug diameter.According to the Mises yield criterion in the process of the study, the boundary of the plastic zone is determined. We set a ratio of bottom boundary for the first time to describe the relative energy of the downward transmission. Wavelets calculated in this study is different from the previous. It is no longer confined to give pressure pulse in spherical cavity to calculate wavelets, but consider about the entire process from source excitation to the formation of wavelets. In this study we use the method of numerical simulation to compute frequency component of excited seismic waves and compare them with different excitation parameters in limestone and soil. We found that when the rock properties is different, the influence of dose, explosive velocity and drug diameter parameters on excitation effect is also different, which is scarcely found in previous studies.Finally, we give some suggestions about the choice of excitation parameters. For high-velocity media such as limestone, we choose the explosive of small dose (about 4kg), high detonation velocity (6900m/s of TNT explosive may be the best), short and thick column, and choose proper filling media with sealed well; While for low-velocity media such as soil, we choose the explosive of small dose, low detonation velocity, slender and long column, and also choose proper filling media with sealed well.