The interest in measuring the scattering matrix for higher order modes in ducts with flow has increased recently and measurements have been made on rectangular and circular ducts.^1–3 One of the advantages of including higher order modes is the possibility to increase the frequency range in which measurements can be made. Recently, new models are proposed to describe the wave propagation constants for plane waves and higher order modes in turbulent pipe flows.^3,4 To verify these models, it is necessary to perform precise acoustic measurements where the uncertainty in the measurement data has been assessed.

中文翻译：

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使用线性方法评估声散射矩阵的随机误差

最近，对于在具有流动性的管道中测量高阶模的散射矩阵的兴趣有所增加，并且已经对矩形和圆形管道进行了测量。^1–3包含高阶模式的优点之一是可以增加可以进行测量的频率范围。最近，提出了新的模型来描述湍流管流中平面波和高阶模的波传播常数。^3,4为验证这些模型，有必要在评估了测量数据不确定性的情况下执行精确的声学测量。