Synthesizing Virtual Measurements of moving Sound Sources in the Atmospheric Boundary Layer
* Presenting author
Abstract:
Environmental noise by traffic has a strong impact on human health and well-being. Microphone array methods are able to determine distinct sound emitting parts of aicraft and trains. The identification and characterization of these sources is essential for the development of tailored mitigation measures. The international research project LION is dedicated to enhance the accuracy of microphone array methods for moving sound sources. To support the development of novel algorithms, a virtual environment to synthesize test cases will be established. To this end, auralizations are rendered, using time-varying digital filters to account for phenomena like Doppler effect, atmospheric absorption, ground reflection and atmospheric turbulence. For modeling aircraft noise with consideration of atmospheric turbulence, the focus was previously set on the modulation of sound pressure amplitudes. For the synthesis of virtual microphone array data, additionally, an accurate modelling of the phase modulation is crucial. A model incorporating Von Kármán turbulence spectra is envisaged. Time-varying digital filters, which model the effect of atmospheric turbulence on sound propagation, will be based on geometrical acoustical simulations, finite-difference time-domain methods and outdoor measurements. First modeling results will be presented.