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CATEGORIES:Isaac Newton Institute Seminar Series
SUMMARY:WaveHoltz: Wave Based Iterative Scheme for Helmhol
tz Problems - Fortino Garcia (Courant Institute of
Mathematical Sciences)
DTSTART;TZID=Europe/London:20230419T114500
DTEND;TZID=Europe/London:20230419T123000
UID:TALK198736AThttp://talks.cam.ac.uk
URL:http://talks.cam.ac.uk/talk/index/198736
DESCRIPTION:Designing efficient iterative solvers for the Helm
holtz equation is notoriously difficult\, with the
two main difficulties being the resolution requir
ements and the highly indefinite character of the
discretized system of equations. The dependence of
the number of degrees of freedom on the frequency
of the problem requires high frequency Helmholtz
solvers to be: (1) parallel\, memory lean\, and sc
alable\, (2) high order accurate to overcome the p
enalty due to pollution/dispersion errors.\nIn thi
s talk we will introduce the WaveHoltz iteration (
WHI) which makes use of time-domain methods for wa
ve equations to design Helmholtz solvers. We show
that the WaveHoltz iteration is symmetric and posi
tive definite in the continuous setting for energy
conserving boundary conditions. Numerical example
s using various discretization techniques that dem
onstrate the method can be used to solve problems
with rather high wave numbers in a memory lean and
scalable fashion will be presented\, as well as r
ecent extensions to problems in elastic media.\nTh
is is joint work with Daniel Appelö\; (MSU)\,
Olof Runborg (KTH)\, and Allen Alvarez Loya (Los A
lamos National Laboratory)
LOCATION:Seminar Room 1\, Newton Institute
CONTACT:
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