Document Type : Research Article


Assistant Professor, Niro Research Institute, Department of Mechanical Rotating Equipment, Tehran, IRAN


Due to the recent applications of generating strong sound waves from thermo-acoustics to acoustic cleaning, it is necessary to modify the previous equations of sound propagation, which were based on linearization assumptions and developed for ordinary applications. In this paper, the sound propagation equations in a horn are first extracted. This starts with writing the equations of momentum and mass conservation and then ends with defining the potential velocity function and placing it in the partial differential equations. By transforming this equation to the frequency domain, the problem becomes a boundary value problem. Frequency response curves are extracted by applying the boundary conditions. These equations can be solved using the Range Kutta method. Since there is an analytical response for exponential horns assuming the sound propagation is linear, the results are validated in this case.


Main Subjects

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