Zobrazeno 1 - 10
of 19
pro vyhledávání: '"Andrew Giuliani"'
Autor:
Andrew Giuliani
Publikováno v:
SIAM Journal on Scientific Computing. 44:A389-A415
We propose a state redistribution method for high order discontinuous Galerkin methods on curvilinear embedded boundary grids. State redistribution relaxes the overly restrictive CFL condition that results from arbitrarily small cut cells and explici
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::f99785f04b4e7aeed00c262c220c14a3
https://doi.org/10.1137/21m1396277
https://doi.org/10.1137/21m1396277
Publikováno v:
Physics of Plasmas. 30:042511
We present a robust optimization algorithm for the design of electromagnetic coils that generate vacuum magnetic fields with nested flux surfaces and precise quasi-symmetry. The method is based on a bilevel optimization problem, where the outer coil
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::cd307d41a785eb0fa0c04b4347950cd9
https://doi.org/10.1063/5.0129716
https://doi.org/10.1063/5.0129716
Publikováno v:
Proceedings of the National Academy of Sciences. 119
Magnetic fields with quasi-symmetry are known to provide good confinement of charged particles and plasmas, but the extent to which quasi-symmetry can be achieved in practice has remained an open question. Recent work [M. Landreman and E. Paul, Phys.
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::2ba1c1cf88b16029b5350a26868d8e10
https://doi.org/10.1073/pnas.2202084119
https://doi.org/10.1073/pnas.2202084119
We propose a new method to compute magnetic surfaces that are parametrized in Boozer coordinates for vacuum magnetic fields. We also propose a measure for quasisymmetry on the computed surfaces and use it to design coils that generate a magnetic fiel
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::92d003ae247ebe0d22c49d49c6cc5cbf
http://arxiv.org/abs/2203.03753
http://arxiv.org/abs/2203.03753
Stochastic and a posteriori optimization to mitigate coil manufacturing errors in stellarator design
It was recently shown in Wechsung et al (2022 Proc. Natl Acad. Sci. USA 119 e2202084119) that there exist electromagnetic coils that generate magnetic fields, which are excellent approximations to quasi-symmetric fields and have very good particle co
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::dea2f1ed7ff707796e8b71edee1e2a79
Autor:
Andrew Giuliani, Lilia Krivodonova
Publikováno v:
Journal of Computational Physics. 381:67-90
We present novel algorithms for cell-based adaptive mesh refinement on unstructured meshes of triangles on graphics processing units. Our implementation makes use of improved memory management techniques and a coloring algorithm for avoiding race con
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::425a9a02f43bc59cbc9a4e6b85d2bb7e
https://doi.org/10.1016/j.jcp.2018.12.019
https://doi.org/10.1016/j.jcp.2018.12.019
Autor:
Andrew Giuliani, Lilia Krivodonova
Publikováno v:
SIAM Journal on Scientific Computing. 41:A508-A537
We propose a second order limiter for the discontinuous Galerkin method applied to hyperbolic conservation laws. We prove that under a suitable time step restriction, the limiter enforces the local...
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::0d47f8a4261bf2966cdc52988fbaa7d6
https://doi.org/10.1137/17m1159038
https://doi.org/10.1137/17m1159038
Autor:
Andrew Giuliani, Lilia Krivodonova
Publikováno v:
Applied Numerical Mathematics. 135:165-172
We show that the theory for strong stability preserving (SSP) time stepping methods employed with the method of lines-type discretizations of hyperbolic conservation laws may result in overly stringent time step restrictions. We analyze a fully discr
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::59b7087b43a779817c223442e37b49b4
https://doi.org/10.1016/j.apnum.2018.08.015
https://doi.org/10.1016/j.apnum.2018.08.015
Publikováno v:
Nuclear Fusion. 62:076034
We extend the single-stage stellarator coil design approach for quasi-symmetry on axis from (Giuliani et al 2020) to additionally take into account coil manufacturing errors. By modeling coil errors independently from the coil discretization, we have
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::a1291ade5eeab886ba4fdf84826853ce
https://doi.org/10.1088/1741-4326/ac45f3
https://doi.org/10.1088/1741-4326/ac45f3
We present a new coil design paradigm for magnetic confinement in stellarators. Our approach directly optimizes coil shapes and coil currents to produce a vacuum quasi-symmetric magnetic field with a target rotational transform on the magnetic axis.
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::edc3d23e34b60dc522675564cb669910
http://arxiv.org/abs/2010.02033
http://arxiv.org/abs/2010.02033