Dynamic Simulation of Traffic Noise by Applying Ray Tracing Method based on Indoor Space Partitioning
Zhibin Chen
Ming Cai
Feng Li
Weijia Ye
Abstract
This study presents a revised 3 dimensional ray tracing method by combining with indoor space partitioning. This method divides an entire indoor space into limited convex polyhedron subspaces, and thus reduces the number of surfaces intersected with rays, and omits the validity test
of the collision point on the reflecting surfaces. Combining with a microscopic traffic simulation tool and a vehicle noise emission model, and taking the influence of diffraction into account, the method can be utilized inulating dynamically the process of traffic noise diffusing inside the
building through windows. Meanwhile, this study selects two different types of architectural layouts in order to demonstrate this method's efficiency, the influence of diffraction and of the state of windows, the differences in indoor noise on different floors and the comparison of indoor
and outdoor traffic noise distribution. A comparison study on before-and-after indoor space partitioning shows that the method is efficient, with about 60% optimization rate. Further, with windows open, the level difference between average indoor and outdoor traffic noise is 7.5 dB, while
it can reach to 12.8 dB with windows closed.