Effect of Cross-Sectional Area Discontinuities in Closed Hard-Walled Ducts on Frequency of Longitudinal Modes

• Autorzy: Meissner M.
• Języki publikacji: EN

Abstrakty

EN

A simple analytical method is developed to estimate frequencies of longitudinal modes in closed hard-walled ducts with discontinuities in a cross-sectional area. The approach adopted is based on a general expression for the acoustic impedance for a plane wave motion in a duct and conditions of impedance continuity at duct discontinuities. Formulae for mode frequencies in a form of transcendental equations were found for one, two and three discontinuities in a duct cross-section. An accuracy of the method was checked by a comparison of analytic predictions with calculation data obtained by use of numerical implementation based on the forced oscillator method with a finite difference algorithm.

Słowa kluczowe

EN

longitudinal duct modes; discontinuity in duct cross-section; contraction ratio

• Wydawca: Instytut Podstawowych Problemów Techniki PAN ; Komitet Akustyki PAN ; Polskie Towarzystwo Akustyczne
• Czasopismo: Archives of Acoustics
• Rocznik: 2010
• Tom: Vol. 35, No. 3
• Strony: 421--435
• Opis fizyczny: Bibliogr. 15 poz., wykr.

Twórcy

autor

Meissner M.

• Institute of Fundamental Technological Research Polish Academy of Sciences Pawinskiego 5B, 02-106 Warszawa, Poland,

Bibliografia

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