Acoustic Nearfield and Farfield for Vibrating Piston in Geometrical and Intensity Formulations |
| M.S. Kozień
Institute of Applied Mechanics, Cracow University of Technology, al. Jana Pawła II 37, 31-864 Cracow, Poland |
| Full Text PDF |
| In classic acoustics there are two areas identified around acoustic sources - nearfield and farfield. The nearfield is connected with the Fresnel solution and farfield - the Fraunhofer one. For each regions there are different theoretical formulae for determination of distribution of the chosen acoustic parameter. Unfortunately there is no sharply outlined border between regions. Therefore one of the important problem, is to define approximately conditions for state the border between them. The two attempts for identification are discussed, i.e. geometrical one and intensity ones. The results are shown on the vibrating circular rigid piston case. |
| DOI: 10.12693/APhysPolA.121.A-132 PACS numbers: 43.20.Bi, 43.20.Tb, 43.40.Rj |