计算气动声学中的紧致滤波格式

 从理论上分析了数值伪波产生的原因，要消除数值伪波可用滤波方法。为了使滤波器具有理想的截断特性，引入了修正的高斯函数。通过让滤波器的频响函数与修正的高斯函数逼近，利用序列二次规划(SQP)方法优化了五对角紧致滤波格式。优化的滤波格式提高了计算精度和效率，增强了数值稳定性，更易于实施。一维和二维算例体现了优化滤波格式的性能改进。

Compact Filtering Schemes for Computational Aeroacoustics

In this article spurious waves introduced in the computation of aeroacoustics are analyzed theoretically and filters are proposed to attenuate these waves as soon as they are generated.In order to obtain a sharp cutoff of the pentadiagonal filters,a modified Gaussian function is introduced.The transfer functions of the filters are forced to be approximated to the modified Gaussian function in a specific wavenumber domain.The sequential quadratic programming(SQP) method is employed to achieve the approximati...