滤波策略对噪声场影响的研究

Study on the Impact of Filtering Strategies for Noise Calculation

本文通过对二维轴对称射流场进行直接数值模拟,探讨了不同滤波策略对噪声场的影响。空间导数的离散采用六阶紧致差分格式,数值非稳定性的控制采用紧致10阶低滤波格式,时间推进采用四步四阶Runge-Kutta格式。对比分析了显式10阶与紧致10阶滤波格式,低存储3阶Runge-Kutta格式与四步四阶Runge-Kutta格式,交错阿格与同位网格方法等几种抑制寄生波方案。分析结果表明,在上述诸多抑制寄生波的方案中,采用交错网格法,计算过程最稳定、最有效。

In this paper, the impact of different filtering strategies for noise calculation is in- vestigated through direct numerical simulation of two-dimensional axisymmetric flow field. It is based on fourth order Runge-Kutta schemes for temporal discretization and sixth order compact finite-difference schemes for spatial discretization coupled with up to lOth-order low-pass filters which is adopted to control numerical stability. The suppression of the parasitic waves solutions were evaluated through comparison between explicit 10th-order and compact 10th-order filters,low-storage third-order Runge-Kutta scheme with four-step fourth-order Runge-Kutta scheme, the Parity grid method and the staggered grid method. The results show that in many above scenarios of inhibi- tion of parasitic waves, the calculation process of using staggered grid is most stable and most effective.