000021510 001__ 21510
000021510 005__ 20170622131249.0
000021510 04107 $$aeng
000021510 046__ $$k2017-06-15
000021510 100__ $$aBrun, Michael
000021510 24500 $$aHYBRID ASYNCHRONOUS PERFECTLY MATCHED LAYER FOR SEISMIC WAVE PROPAGATION IN 2D AND 3D UNBOUNDED DOMAINS

000021510 24630 $$n6.$$pComputational Methods in Structural Dynamics and Earhquake Engineering
000021510 260__ $$bNational Technical University of Athens, 2017
000021510 506__ $$arestricted
000021510 520__ $$2eng$$aPerfectly Matched Layer (PML) is recognized as a very effective tool for modeling unbounded domains. Nonetheless, the computation time required by the PML may be large, especially when an explicit time integration scheme is adopted for dealing with the wave propagation problem both in the domain of interest and in the PML medium. In this paper, it is proposed to investigate subdomain strategies enabling the appropriate time integration scheme in the PML with its own time step to be chosen, independently of the choice of the time scheme in the domain of interest. We focus on explicit time integrator in the physical subdomain (Central Difference scheme) associated with a fine time step satisfying the CFL stability criterion. The PML formulation proposed by Basu and Chopra ([1]) for 2D transient dynamics, has been coupled with the interior physical subdomain using the dual Schur approach proposed by Gravouil and Combescure ([2]). Hybrid (implicit time integrator for the PML) asynchronous (multi time steps) PMLs have been derived. In order to highlight the accuracy of the hybrid asynchronous PMLs, 2D numerical applications have been investigated such as Lamb’s test, rigid footing on a half space and on a layered half space. Excellent agreement has been achieved in comparison to the full explicit computation with an extended mesh. The result accuracy decreases when large time steps in the PML are considered. Other PML formulations could be employed using the presented framework. 3D implementations of absorbing layers have been achieved to mimic the semi-infinite medium, based on either viscous damping Rayleigh formulation or PML formulation. The efficiency of the different methods was compared. Finally, weak coupling in time has been investigated on the basis of the recent works ([3], [4]), enabling to adopt more advanced time integrators as α methods for damping out the high frequencies due to the finite element discretization.

000021510 540__ $$aText je chráněný podle autorského zákona č. 121/2000 Sb.
000021510 653__ $$aPerfect Matched Layers (PML), elastic wave, 2D and 3D transient analysis, subdomain coupling, Hybrid Asynchronous PML

000021510 7112_ $$aCOMPDYN 2017 - 6th International Thematic Conference$$cRhodes Island (GR)$$d2017-06-15 / 2017-06-17$$gCOMPDYN2017
000021510 720__ $$aBrun, Michael$$iDjeran-Maigre, Irini$$iLi, Sijia$$iZafati, Eliass
000021510 8560_ $$ffischerc@itam.cas.cz
000021510 8564_ $$s118410$$uhttps://invenio.itam.cas.cz/record/21510/files/16756.pdf$$yOriginal version of the author's contribution as presented on CD, section: [MS10] Advances in Numerical Methods for Linear and Non-Linear Dynamics and Wave Propagation
.
000021510 962__ $$r21500
000021510 980__ $$aPAPER