The Herschel-Quincke tube concept as a noise control device for turbofan engines

Analytical and numerical modeling, sensitivity analysis, and multi-objective optimization of the acoustic performance of the herschel-quincke tube

“…So, the optimal design for the HQ tube would be maximizing TL value and at the same time minimizing its backpressure or BP. This rather simple principle of wave cancellation has been used in several configurations of the present-day automotive mufflers that combine the advantage of wideband TL with remarkably low backpressure [3,8,19].…”

“…He found that the maximum transmission loss is when the path length difference is ((2 m + 1)k/2), and mk with less attenuation at other frequencies, where k is the wavelength of the acoustic wave, and m is an integer. Stewart's model assumed that the cross-sectional areas of the parallel ducts were equal [3]. Selamet and Easwaran generalized the classical two-duct Herschel-Quincke (HQ) tube to an nduct configuration [4].…”