BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//IEEE Toronto Section - ECPv6.15.17//NONSGML v1.0//EN
CALSCALE:GREGORIAN
METHOD:PUBLISH
X-WR-CALNAME:IEEE Toronto Section
X-ORIGINAL-URL:https://www.ieeetoronto.ca
X-WR-CALDESC:Events for IEEE Toronto Section
REFRESH-INTERVAL;VALUE=DURATION:PT1H
X-Robots-Tag:noindex
X-PUBLISHED-TTL:PT1H
BEGIN:VTIMEZONE
TZID:America/New_York
BEGIN:DAYLIGHT
TZOFFSETFROM:-0500
TZOFFSETTO:-0400
TZNAME:EDT
DTSTART:20210314T070000
END:DAYLIGHT
BEGIN:STANDARD
TZOFFSETFROM:-0400
TZOFFSETTO:-0500
TZNAME:EST
DTSTART:20211107T060000
END:STANDARD
BEGIN:DAYLIGHT
TZOFFSETFROM:-0500
TZOFFSETTO:-0400
TZNAME:EDT
DTSTART:20220313T070000
END:DAYLIGHT
BEGIN:STANDARD
TZOFFSETFROM:-0400
TZOFFSETTO:-0500
TZNAME:EST
DTSTART:20221106T060000
END:STANDARD
BEGIN:DAYLIGHT
TZOFFSETFROM:-0500
TZOFFSETTO:-0400
TZNAME:EDT
DTSTART:20230312T070000
END:DAYLIGHT
BEGIN:STANDARD
TZOFFSETFROM:-0400
TZOFFSETTO:-0500
TZNAME:EST
DTSTART:20231105T060000
END:STANDARD
END:VTIMEZONE
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20220503T110000
DTEND;TZID=America/New_York:20220503T120000
DTSTAMP:20260416T024323
CREATED:20220502T172040Z
LAST-MODIFIED:20220504T073258Z
UID:10000350-1651575600-1651579200@www.ieeetoronto.ca
SUMMARY:Higher Order Globally Constraint-Preserving FVTD and DGTD Schemes for Time-Dependent Computational Electrodynamics (Prof. Dinshaw Balsara\, U. of Notre-Dame)
DESCRIPTION:Adaptive mesh refinement (AMR) is the art of solving PDEs on a mesh hierarchy with increasing mesh refinement at each level of the hierarchy. Accurate treatment on AMR hierarchies requires accurate prolongation of the solution from a coarse mesh to a newly-defined finer mesh. For scalar variables\, suitably high order finite volume WENO methods can carry out such a prolongation. However\, classes of PDEs\, like computational electrodynamics (CED) and magnetohydrodynamics (MHD)\, require that vector fields preserve a divergence constraint. The primal variables in such schemes consist of normal components of the vector field that are collocated at the faces of the mesh. As a result\, the reconstruction and prolongation strategies for divergence constraint-preserving vector fields are necessarily more intricate. \nIn this seminar\, we present a fourth order divergence constraint-preserving prolongation strategy that is analytically exact. Extension to higher orders using analytically exact methods is very challenging. To overcome that challenge\, a novel WENO-like reconstruction strategy is invented that matches the moments of the vector field in the faces where the vector field components are collocated. This approach is almost divergence constraint-preserving; so we call it WENO-ADP. To make it exactly divergence constraint-preserving\, a touch-up procedure is developed that is based on a constrained least squares (CLSQ) based method for restoring the divergence constraint up to machine accuracy. With the touch-up\, it is called WENO-ADPT. It is shown that refinement ratios of two and higher can be accommodated. An item of broader interest in this work is that we have also been able to invent very efficient finite volume WENO methods where the coefficients are very easily obtained and the multidimensional smoothness indicators can be expressed as perfect squares. We demonstrate that the divergence constraint-preserving strategy works at several high orders for divergence-free vector fields as well as vector fields where the divergence of the vector field has to match a charge density and its higher moments. We also show that our methods overcome the late time instability that has been known to plague adaptive computations in Computational Electrodynamics. \nCo-sponsored by: Center for Computational Science and Engineering (CCSE)\, University of Toronto \nSpeaker(s): Prof. Dinshaw Balsara\, \nRegister: https://events.vtools.ieee.org/m/312555 \nBiography: Dinshaw S. Balsara received the Ph.D. degree in computational physics and astrophysics from the University of Illinois at Urbana-Champaign\, Champaign\, IL\, USA\, in 1990. He is currently a Professor with the Department of Physics and the Department of Applied and Computational Mathematics and Statistics at the University of Notre Dame. He has developed computational algorithms and applications in the areas of interstellar medium\, turbulence\, star formation\, planet formation\, the physics of accretion disks\, compact objects\, and relativistic astrophysics. Many of the algorithms developed by him for higher order methods have seen extensive use and have been copiously cited.\,Dr. Balsara was the recipient of the 2014 Department of Energy Award of Excellence for significant contributions to the Stockpile Stewardship Program and the 2017 Global Initiative on Academic Networks Award from the Government of India. He serves the community as an Associate Editor of Journal of Computational Physics and Computational Astrophysics and Cosmology.
URL:https://www.ieeetoronto.ca/event/high-order-adaptive-mesh-refinement-amr-for-divergence-constraint-preserving-schemes-focus-on-mhd-and-ced-prof-dinshaw-balsara-university-of-notre-dame/
LOCATION:Virtual: https://events.vtools.ieee.org/m/312555
CATEGORIES:Electromagnetics & Radiation
ORGANIZER;CN="Costas Sarris":MAILTO:costas.sarris@utoronto.ca
END:VEVENT
END:VCALENDAR