Terrain Effect on Aircraft Noise

• Main Authors: Jing-Hou Hu, 胡景灝
• Other Authors: C.C. Chao,Hung-Sying Jing
• Format: Others
• Language: zh-TW
• Published: 1994
• Online Access: http://ndltd.ncl.edu.tw/handle/28882409941563107464

碩士 === 國立成功大學 === 航空太空工程學系 === 82 === The purpose of this research is to analyse and simulate the terrain effect on aircraft noise, we are looking forward to be helpful on analyzing aircraft noise of Taiwan. Terrain effect on aircraft noise is to solve scattering problem. For general obstacle shapes, the most popular numerical method on scattering problem is the boundary element method (B.E.M.), yet it is difficult on implementation and it needs modifications for the obstacle shape with shape edge or at some characterestic wavenumbers. We use the method of fundamental solution (M.F.S.) to solve scattering problem in this research. M.F.S. is developed much later then B.E.M., it won't add burdden on implementation at characterestic wavenumber occured in B.E.M., so it is suitable for solving general scattering problem. This method uses finite simulation point sources inside obstacle to simulate the scattering field. Put our numerical result and analytical solution or solution of B.E.M. into comparison, if the chosen grid points on on obstacle reaches some amount we need only small quantity of simulation point sources to simulate scattering field. In this research it is assume that airplane is a moving point source, using M.F.S. combined with the boundary condition of half plane and finite impedence to simulate the aircraft noise field. A simulation example of aircraft noise contour plot is given.