the elastic wave propagation over the shape transitions of bodies.

THE ELASTIC WAVE PROPAGATION OVER THE SHAPE
TRANSITIONS OF BODIES.
Š.Morávka, P.Hora
Summary: Due to using non-destructive diagnostics method – the acoustic
emission- there is required the best knowledge about the rules of the elastic
wave propagation in bodies. So this work treats the elastic wave propagation
in the basic construction elements of structures. The samples with the most
common shape transitions are used – here some experimental bodies with the
shoulders (like a stair shape) at various sizes. The results of the analytical
computations, numerical simulations and experimental results are verified and
compared mutually. The generalized ray theory - one from the analytical
methods - is applied. For the extensive numerical simulations the finite element
method (implemented in software MARC/MENTAT) is used. The transient
piezoceramics transducers are employed for the experimental measuring.
Úvod.
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__________________________________________________________________________________________________________________________________________________
Dr.Ing.Štefan Morávka, E-mail: [email protected], Ing. Petr Hora, CSc., E-mail:
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Literatura.
[1] Hora P. & al.: Nové PHWRG\Y\KRGQRFRYiQtVLJQiO
R HãHQtJUDQWX*$ý5þ3O]H
DNXVWLFNpHPLVH=iY UHþQi]SUiYD
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[2] Pao Y.-H., Gajewski R. R.: The Generalized Ray Theory and Transient Responses of
Layered Elastic Solids. In: Physical Acoustics, Edited by Warren P. Mason and R. N.
Thurston, Vol. 13, Academic Press New York, 1977.
>@ +RUD 3 7HRULH ]REHFQ QpKR SDSUVNX D DQDOê]D WUDQ]LHQWQtFK YOQ YH YtFHYUVWYpP
SHYQpPW OHVH9ê]NXPQi]SUiYD93Ò766.ý6$93O]H
>@ 0RUiYND â 3RURYQiQt DQDO\WLFNpKR
HãHQt QHVWDFLRQiUQt Ui]RYp QDSMDWRVWL NRQWLQXD
sYêSRþWHPSRPRFt0.36WURMQtFN\þDVþVWU%UDWLVODYD
>@0RUiYNDâ6SROHþQpSRVRX]HQtYHGOHMãtFK~þLQN
SURVWRURYpDþDVRYpGLVNUHWL]DFHS L
QHVWDFLRQiUQtP]DWtåHQt,Q1iURGQtNRQIHUHQFH,QåHQêUVNiPHFKDQLND
’99, Svratka, 1999.
[6] Proctor T. M. Jr.: An Improved Piezoelectric Acoustic Emission Transducer., J.Acoust.
Soc. Am., vol. 71, pp. 1163-1168, No. 5, 1982.
>@ 0RUiYND â $QDOê]D ãLURNRSiVPRYpKR VQtPDþH QDS
RYêFK YOQ Kolokvium
'LDJQRVWLNDDDNWLYQt t]HQt’98, Brno, VUT, 1998.
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