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Optimisation of confinement in a fusion reactor using a nonlinear turbulence model

Published online by Cambridge University Press:  23 April 2018

E. G. Highcock*
Affiliation:
Department of Physics, Chalmers University of Technology, Fysikgården 1, 41258 Gothenburg, Sweden Rudolph Peierls Centre for Theoretical Physics, 1 Keble Road, Oxford, OX1 3NP, UK Culham Centre for Fusion Energy, Culham Science Centre, Abingdon, OX14 3DB, UK
N. R. Mandell
Affiliation:
Department of Astrophysical Sciences, Princeton University, Princeton NJ, 08540, USA
M. Barnes
Affiliation:
Rudolph Peierls Centre for Theoretical Physics, 1 Keble Road, Oxford, OX1 3NP, UK
W. Dorland
Affiliation:
Department of Physics, University of Maryland, College Park, MD, 20742, USA
*
Email address for correspondence: highcock@chalmers.se

Abstract

The confinement of heat in the core of a magnetic fusion reactor is optimised using a multidimensional optimisation algorithm. For the first time in such a study, the loss of heat due to turbulence is modelled at every stage using first-principles nonlinear simulations which accurately capture the turbulent cascade and large-scale zonal flows. The simulations utilise a novel approach, with gyrofluid treatment of the small-scale drift waves and gyrokinetic treatment of the large-scale zonal flows. A simple near-circular equilibrium with standard parameters is chosen as the initial condition. The figure of merit, fusion power per unit volume, is calculated, and then two control parameters, the elongation and triangularity of the outer flux surface, are varied, with the algorithm seeking to optimise the chosen figure of merit. A twofold increase in the plasma power per unit volume is achieved by moving to higher elongation and strongly negative triangularity.

Type
Research Article
Copyright
© Cambridge University Press 2018 

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