Accuracy and convergence of coupled finitevolume/Monte Carlo codes for plasma edge simulations of nuclear fusion reactors
Abstract
The plasma and neutral transport in the plasma edge of a nuclear fusion reactor is usually simulated using coupled finite volume (FV)/Monte Carlo (MC) codes. However, under conditions of future reactors like ITER and DEMO, convergence issues become apparent. This paper examines the convergence behaviour and the numerical error contributions with a simplified FV/MC model for three coupling techniques: Correlated Sampling, Random Noise and Robbins Monro. Also, practical procedures to estimate the errors in complex codes are proposed. Moreover, first results with more complex models show that an order of magnitude speedup can be achieved without any loss in accuracy by making use of averaging in the Random Noise coupling technique.
 Authors:
 KU Leuven, Department of Mechanical Engineering, Celestijnenlaan 300A, 3001 Leuven (Belgium)
 KU Leuven, Department of Computer Science, Celestijnenlaan 200A, 3001 Leuven (Belgium)
 Institute of Energy and Climate Research (IEK4), FZ Jülich GmbH, D52425 Jülich (Germany)
 Publication Date:
 OSTI Identifier:
 22572360
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Journal of Computational Physics; Journal Volume: 322; Other Information: Copyright (c) 2016 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ERRORS; ITER TOKAMAK; MONTE CARLO METHOD; NOISE; PLASMA; SIMULATION
Citation Formats
Ghoos, K., Email: kristel.ghoos@kuleuven.be, Dekeyser, W., Samaey, G., Börner, P., and Baelmans, M.. Accuracy and convergence of coupled finitevolume/Monte Carlo codes for plasma edge simulations of nuclear fusion reactors. United States: N. p., 2016.
Web. doi:10.1016/J.JCP.2016.06.049.
Ghoos, K., Email: kristel.ghoos@kuleuven.be, Dekeyser, W., Samaey, G., Börner, P., & Baelmans, M.. Accuracy and convergence of coupled finitevolume/Monte Carlo codes for plasma edge simulations of nuclear fusion reactors. United States. doi:10.1016/J.JCP.2016.06.049.
Ghoos, K., Email: kristel.ghoos@kuleuven.be, Dekeyser, W., Samaey, G., Börner, P., and Baelmans, M.. Sat .
"Accuracy and convergence of coupled finitevolume/Monte Carlo codes for plasma edge simulations of nuclear fusion reactors". United States.
doi:10.1016/J.JCP.2016.06.049.
@article{osti_22572360,
title = {Accuracy and convergence of coupled finitevolume/Monte Carlo codes for plasma edge simulations of nuclear fusion reactors},
author = {Ghoos, K., Email: kristel.ghoos@kuleuven.be and Dekeyser, W. and Samaey, G. and Börner, P. and Baelmans, M.},
abstractNote = {The plasma and neutral transport in the plasma edge of a nuclear fusion reactor is usually simulated using coupled finite volume (FV)/Monte Carlo (MC) codes. However, under conditions of future reactors like ITER and DEMO, convergence issues become apparent. This paper examines the convergence behaviour and the numerical error contributions with a simplified FV/MC model for three coupling techniques: Correlated Sampling, Random Noise and Robbins Monro. Also, practical procedures to estimate the errors in complex codes are proposed. Moreover, first results with more complex models show that an order of magnitude speedup can be achieved without any loss in accuracy by making use of averaging in the Random Noise coupling technique.},
doi = {10.1016/J.JCP.2016.06.049},
journal = {Journal of Computational Physics},
number = ,
volume = 322,
place = {United States},
year = {Sat Oct 01 00:00:00 EDT 2016},
month = {Sat Oct 01 00:00:00 EDT 2016}
}

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