Conference_programme: 13.1 - Noise Barriers / absorbive claddings / diffractive barrier tops
Lecture: Computationally efficient calculation of edge diffraction in time domain
Author(s): Nikolaou Petros, Menounou Penelope
Summary:
The fast and accurate calculation of the diffracted signal caused by edges is important in many practical cases such as road traffic noise diffracted by noise barriers. The authors presented in the past an impulse response solution for diffraction by edges. The diffracted signal is obtained by convolving the impulse response function with any given incident signal. In numerical calculations the impulse response requires fine time sampling to describe its starting values, where it becomes infinite. As a result, the computational time required, to produce convergent/accurate predictions, increases dramatically, particularly in cases involving multiple receivers. In the present work two methods are presented that reduce the computational time. The first is based on the generator curve, a curve that embodies/generates all impulse response functions produced for any source/receiver configuration, thus allowing faster impulse response calculations. The second method relies on the partial time antiderivatives of the impulse response, which are proven to be continuous non-singular functions, expressed in close form, which can replace the impulse response in predicting the diffracted signal. Compared to the impulse response the antiderivatives can produce convergent results with much lesser time samples, thus achieving significant computational advantage. Finally, generator curves are derived for the antiderivatives as well, improving their performance even further.\n
Corresponding author
Name: Mr Petros Nikolaou
e-mail: petros7nikolaou@gmail.com
Country: Greece
