并行时域有限差分法的瞬态声场及其效率分析

建立了适用于二维水下目标声散射声场计算的并行FDTD计算模型,通过计算结果对入射波激励目标的作用过程进行了时域分析,从各个时刻的瞬态声场分布图可以明显看出衍射、透射和散射现象,并且能够直观地给出声场分布形态以及声波传播的物理过程。通过算例测试了其在不同数目节点机参与下的计算耗时、内存耗用、并行加速度和并行效率。分析了计算耗时、内存耗用、并行加速度、并行效率随节点数变化的关系曲线,同时还着重分析了并行效率下降的原因。

Transient Sound Field and Efficiency Analysis with Parallel Finite Difference Time Domain Method

The model of the parallel FDTD method was established to compatibly calculate scattering characteristics of 2D under water target.Time-domain analysis was applied to analyze the course of incident wave inspires with target.According to the numerical result,diffraction phenomena and scattering phenomena from distribution of the transient sound field each time can be distinctly observed,and so do the distribution of the whole sound field and the physical course of sound wave spread.In order to measure the efficiency of the parallel FDTD,the calculation time,using of memory,parallel efficiency,and parallel acceleration under different nodes were analyzed.The cause for decline of the parallel efficiency was discussed.