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Title: A fast, accurate and easy to implement Kapur–Rokhlin quadrature scheme for singular integrals in axisymmetric geometries

Abstract

Many applications in magnetic confinement fusion require the efficient calculation of surface integrals with singular integrands. The singularity subtraction approaches typically used to handle such singularities are complicated to implement and low-order accurate. In contrast, we demonstrate that the Kapur–Rokhlin quadrature scheme is well-suited for the logarithmically singular integrals encountered for a toroidally axisymmetric confinement system, is easy to implement and is high-order accurate. As an illustration, we show how to apply this quadrature scheme for the efficient and accurate calculation of the normal component of the magnetic field due to the plasma current on the plasma boundary, via the virtual-casing principle.

Authors:
ORCiD logo; ORCiD logo; ORCiD logo
Publication Date:
Sponsoring Org.:
USDOE
OSTI Identifier:
1970062
Grant/Contract Number:  
FG02-86ER53223
Resource Type:
Published Article
Journal Name:
Journal of Plasma Physics
Additional Journal Information:
Journal Name: Journal of Plasma Physics Journal Volume: 89 Journal Issue: 2; Journal ID: ISSN 0022-3778
Publisher:
Cambridge University Press (CUP)
Country of Publication:
United Kingdom
Language:
English

Citation Formats

Toler, Evan, Cerfon, A. J., and Malhotra, D. A fast, accurate and easy to implement Kapur–Rokhlin quadrature scheme for singular integrals in axisymmetric geometries. United Kingdom: N. p., 2023. Web. doi:10.1017/S002237782300020X.
Toler, Evan, Cerfon, A. J., & Malhotra, D. A fast, accurate and easy to implement Kapur–Rokhlin quadrature scheme for singular integrals in axisymmetric geometries. United Kingdom. https://doi.org/10.1017/S002237782300020X
Toler, Evan, Cerfon, A. J., and Malhotra, D. Fri . "A fast, accurate and easy to implement Kapur–Rokhlin quadrature scheme for singular integrals in axisymmetric geometries". United Kingdom. https://doi.org/10.1017/S002237782300020X.
@article{osti_1970062,
title = {A fast, accurate and easy to implement Kapur–Rokhlin quadrature scheme for singular integrals in axisymmetric geometries},
author = {Toler, Evan and Cerfon, A. J. and Malhotra, D.},
abstractNote = {Many applications in magnetic confinement fusion require the efficient calculation of surface integrals with singular integrands. The singularity subtraction approaches typically used to handle such singularities are complicated to implement and low-order accurate. In contrast, we demonstrate that the Kapur–Rokhlin quadrature scheme is well-suited for the logarithmically singular integrals encountered for a toroidally axisymmetric confinement system, is easy to implement and is high-order accurate. As an illustration, we show how to apply this quadrature scheme for the efficient and accurate calculation of the normal component of the magnetic field due to the plasma current on the plasma boundary, via the virtual-casing principle.},
doi = {10.1017/S002237782300020X},
journal = {Journal of Plasma Physics},
number = 2,
volume = 89,
place = {United Kingdom},
year = {Fri Apr 14 00:00:00 EDT 2023},
month = {Fri Apr 14 00:00:00 EDT 2023}
}

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