Ιδρυματικό Αποθετήριο
Πολυτεχνείο Κρήτης
Πολυτεχνείο Κρήτης
EN
|
EL
| URI | http://purl.tuc.gr/dl/dias/CE246EDE-494C-4EEC-AACD-F2C861FC874C | - |
| Αναγνωριστικό | http://www.sciencedirect.com/science/article/pii/S0168927411000882 | - |
| Αναγνωριστικό | https://doi.org/10.1016/j.apnum.2011.05.005 | - |
| Γλώσσα | en | - |
| Μέγεθος | 15 pages | en |
| Τίτλος | A finite element discretization of the standard parabolic equation in generalized boundary fitting coordinates | en |
| Δημιουργός | Kampanis, Nikolaos A | en |
| Δημιουργός | Delis Anargyros | en |
| Δημιουργός | Δελης Αναργυρος | el |
| Δημιουργός | Antonopoulou D.C. | en |
| Δημιουργός | Kozyrakis G. | en |
| Εκδότης | Elsevier | en |
| Περίληψη | A simplified, but quantitatively reliable approximation of atmospheric sound propagation is given by the standard parabolic equation. The waveguide is a cylindrically symmetric, unbounded, domain with an irregular lower boundary. The associated initial-boundary value problem uses a mixed-type boundary condition along the lower boundary and a nonlocal, absorbing boundary condition of the DtN (or NtD) type, applied on an artificial upper boundary. Exterior wave fields of a constant index of refraction and a linear, when squared (as function of height) one, are considered. The physical, complex waveguide reduces to an orthogonal computational domain by the means of a numerical transformation to generalized coordinates, fitting the lower, irregular boundary. The technique presented is of practical interest for its proper handling of complex ground topographies; it is interfaced with a mesh generator and processes the topographic data retrieved from a geographic information system, hence the transformation of coordinates is computed numerically. The transformed initial-boundary value problem (on the orthogonal computational domain) is discretized by the Crank–Nicolson in time and a continuous, piecewise linear finite element method in space. The propagation of cylindrically symmetric sound waves over a complex terrain, emitted to the atmosphere by a harmonic source, has been studied. The effectiveness of the numerical method introduced, is exploited on several test cases. | en |
| Τύπος | Peer-Reviewed Journal Publication | en |
| Τύπος | Δημοσίευση σε Περιοδικό με Κριτές | el |
| Άδεια Χρήσης | http://creativecommons.org/licenses/by/4.0/ | en |
| Ημερομηνία | 2015-10-26 | - |
| Ημερομηνία Δημοσίευσης | 2013 | - |
| Θεματική Κατηγορία | Atmospheric acoustics | en |
| Θεματική Κατηγορία | Standard parabolic approximation | en |
| Θεματική Κατηγορία | Irregular ground topography | en |
| Θεματική Κατηγορία | Generalized boundary fitting coordinates | en |
| Θεματική Κατηγορία | Finite element formulation | en |
| Θεματική Κατηγορία | Nonlocal boundary conditions | en |
| Βιβλιογραφική Αναφορά | N. A. Kampanis, A. I. Delis, D. C. Antonopoulou and G. Kozyrakis, "A finite element discretization of the standard parabolic equation in generalized boundary fitting coordinates," Appl. Num. Math., vol. 67, pp. 152-166, May 2013. doi:10.1016/j.apnum.2011.05.005 | en |
Copyright © DIAS 2013
