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arXiv · 1705.03825

Ray-tracing semiclassical low frequency acoustic modeling with local and extended reaction boundaries

Rok Prislan·Daniel Svenšek
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Abstract

The recently introduced acoustic ray-tracing semiclassical (RTS) method is validated for a set of practically relevant boundary conditions. RTS is a frequency domain geometrical method which directly reproduces the acoustic Green's function. As previously demonstrated for a rectangular room and weakly absorbing boundaries with a real and frequency-independent impedance, RTS is capable of modeling also the lowest modes of such a room, which makes it a useful method for low frequency sound field modeling in enclosures. In practice, rooms are furnished with diverse types of materials and acoustic elements, resulting in a frequency-dependent, phase-modifying absorption/reflection. In a realistic setting, we test the RTS method with two additional boundary conditions: a local reaction boundary simulating a resonating membrane absorber and an extended reaction boundary representing a porous layer backed by a rigid boundary described within the Delany-Bazley-Miki model, as well as a combination thereof. The RTS-modeled spatially dependent pressure response and octave band decay curves with the corresponding reverberation times are compared to those obtained by the finite element method.

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Rok Prislan, Daniel Svenšek. 2017-05-10. Ray-tracing semiclassical low frequency acoustic modeling with local and extended reaction boundaries. https://doi.org/10.1016/j.jsv.2018.08.041

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