【摘要】 针对刚性边界条件、衰减边界条件与透射边界条件对弹性波场的影响及计算中产生的数值频散现象,将衰减边界与透射边界双重作用于人工边界,引入了混合边界条件,并在计算中采用了微量阻尼的方法,结果表明,混合边界条件能更好地吸收人工边界的反射;数值频散的阻尼算法能大大减弱由网格剖分、计算误差造成的频散现象。该方法可有效提高波场模拟精度。更多还原

【Abstract】 Aiming at the effects of rigid boundary condition, attenuation boundary condition and transmitting boundary condition on elastic wave field and the numerical frequency dispersion in calculation, the writers apply attenuation boundary condition and transmitting boundary condition as a mixed boundary one on artificial boundary, introduce mixed boundary condition into elastic wave numerical simulation, and adopt micro-damp in the caculation at the same time. The results prove that mixed boundary condition is better in absorbing the reflection of artificial boundary. Besides, the micro-damp method used in the calculation of numerical frequency dispersion can weaken the frequency dispersion caused by the division of grid and the computational error. This method can improve the precision effectively in the wave field simulation.更多还原