Prediction of sound field in large area by using a hybrid ray-tracing Method

To predict the sound field emitted by a large horn-loaded speaker in outdoor area, a hybrid ray-tracing algorithm is presented in this paper. In a short distance sound field the straight line ray-tracing is applied and for the long distance sound field a curved raytracing method is used, in which the ground effect, air absorption and wind speed are considered. The predicted results are compared with those of the measured data. It has shown that the predicted sound pressure levels at various positions are close to the measurement results. Finally, the influence of frequency, air absorption coefficient and wind speed on the sound propagation in outdoor area is analyzed according to the numerical results of the hybrid method.