A theoretical and experimental investigation of the throat impedance characteristics of constant directivity horns.

Autor: McLean, James S., Post, John T., Hixson, Elmer L.
Zdroj: Journal of the Acoustical Society of America; 1992, Vol. 92 Issue 5, p2509-2520, 12p
Abstrakt: Constant directivity horns exhibit controlled radiation patterns over a broad frequency range by making use of complicated flare geometries sometimes containing discontinuities. Although the radiative properties of such horns are well documented, the throat impedance and power transfer characteristics have not been as thoroughly investigated. A study of the throat impedance characteristics of constant directivity horns has been performed. A general transmission matrix model for acoustic horns with arbitrary flare has been developed. The model is shown to be equivalent to the Webster equation when losses are negligible. Also, a new experimental method for accurately making throat impedance measurements has been developed. Measurements of the throat impedance of a typical constant directivity horn are presented and confirm the predictions of the model. It is shown that the resonance characteristics of the acoustic throat impedance of constant directivity horns are due to reflections at the diffraction slot discontinuity. [ABSTRACT FROM AUTHOR]
Databáze: Complementary Index