Recent advances in stellarator optimization

Gates, D. A.; Boozer, A. H.; Brown, T.; Breslau, J.; Curreli, D.; Landreman, M.; Lazerson, S. A.; Lore, J.; Mynick, H.; Neilson, G. H.; Pomphrey, N.; Xanthopoulos, P.; Zolfaghari, A.

doi:10.1088/1741-4326/aa8ba0

Recent advances in stellarator optimization

Journal Article · Fri Oct 27 00:00:00 EDT 2017 · Nuclear Fusion

DOI:https://doi.org/10.1088/1741-4326/aa8ba0· OSTI ID:1414907

^[1]; Boozer, A. H. ^[2]; Brown, T. ^[1]; Breslau, J. ^[1]; Curreli, D. ^[3]; ^[4]; ^[1]; Lore, J. ^[5]; Mynick, H. ^[1]; Neilson, G. H. ^[1]; Pomphrey, N. ^[1]; Xanthopoulos, P. ^[6]; Zolfaghari, A. ^[1]

Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
Columbia Univ., New York, NY (United States)
Univ. of Illinois, Urbana-Champaign, IL (United States)
Univ. of Maryland, College Park, MD (United States)
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Max Planck Inst. for Plasma Physics, Greifswald (Germany)

Computational optimization has revolutionized the field of stellarator design. To date, optimizations have focused primarily on optimization of neoclassical confinement and ideal MHD stability, although limited optimization of other parameters has also been performed. Here, we outline a select set of new concepts for stellarator optimization that, when taken as a group, present a significant step forward in the stellarator concept. One of the criticisms that has been leveled at existing methods of design is the complexity of the resultant field coils. Recently, a new coil optimization code—COILOPT++, which uses a spline instead of a Fourier representation of the coils,—was written and included in the STELLOPT suite of codes. The advantage of this method is that it allows the addition of real space constraints on the locations of the coils. The code has been tested by generating coil designs for optimized quasi-axisymmetric stellarator plasma configurations of different aspect ratios. As an initial exercise, a constraint that the windings be vertical was placed on large major radius half of the non-planar coils. Further constraints were also imposed that guaranteed that sector blanket modules could be removed from between the coils, enabling a sector maintenance scheme. Results of this exercise will be presented. New ideas on methods for the optimization of turbulent transport have garnered much attention since these methods have led to design concepts that are calculated to have reduced turbulent heat loss. We have explored possibilities for generating an experimental database to test whether the reduction in transport that is predicted is consistent with experimental observations. Thus, a series of equilibria that can be made in the now latent QUASAR experiment have been identified that will test the predicted transport scalings. Fast particle confinement studies aimed at developing a generalized optimization algorithm are also discussed. A new algorithm developed for the design of the scraper element on W7-X is presented along with ideas for automating the optimization approach.

View Accepted Manuscript (DOE)

Research Organization:: Princeton Plasma Physics Laboratory (PPPL), Princeton, NJ (United States)

Sponsoring Organization:: USDOE

Grant/Contract Number:: AC02-09CH11466

OSTI ID:: 1414907

Alternate ID(s):: OSTI ID: 22738466

Journal Information:: Nuclear Fusion, Journal Name: Nuclear Fusion Journal Issue: 12 Vol. 57; ISSN 0029-5515

Publisher:: IOP ScienceCopyright Statement

Country of Publication:: United States

Language:: English

References (62)

Effects of Net Currents on the Magnetic Configuration of W7-X Geiger, J.; Beidler, C. D.; Drevlak, M. Contributions to Plasma Physics, Vol. 50, Issue 8 https://doi.org/10.1002/ctpp.200900028	journal	July 2010
Development of Divertor Concept for Optimized Stellarators Nührenberg, J.; Strumberger, E. Contributions to Plasma Physics, Vol. 32, Issue 3-4 https://doi.org/10.1002/ctpp.2150320306	journal	January 1992
Quasi-helically symmetric toroidal stellarators Nührenberg, J.; Zille, R. Physics Letters A, Vol. 129, Issue 2 https://doi.org/10.1016/0375-9601(88)90080-1	journal	May 1988
A 3D Monte Carlo code for plasma transport in island divertors Feng, Y.; Sardei, F.; Kisslinger, J. Journal of Nuclear Materials, Vol. 241-243 https://doi.org/10.1016/S0022-3115(97)80168-7	journal	February 1997
3D fluid modelling of the edge plasma by means of a Monte Carlo technique Feng, Y.; Sardei, F.; Kisslinger, J. Journal of Nuclear Materials, Vol. 266-269 https://doi.org/10.1016/S0022-3115(98)00844-7	journal	March 1999
Service oriented architecture for scientific analysis at W7-X. An example of a field line tracer Bozhenkov, S. A.; Geiger, J.; Grahl, M. Fusion Engineering and Design, Vol. 88, Issue 11 https://doi.org/10.1016/j.fusengdes.2013.07.003	journal	November 2013
A 3D Monte Carlo code for plasma transport in island divertors Feng, Y.; Sardei, F.; Kisslinger, J. Journal of Nuclear Materials, Vol. 241-243 https://doi.org/10.1016/s0022-3115(97)80168-7	journal	February 1997
3D fluid modelling of the edge plasma by means of a Monte Carlo technique Feng, Y.; Sardei, F.; Kisslinger, J. Journal of Nuclear Materials, Vol. 266-269 https://doi.org/10.1016/s0022-3115(98)00844-7	journal	March 1999
Stellarator design Boozer, Allen H. Journal of Plasma Physics, Vol. 81, Issue 6 https://doi.org/10.1017/S0022377815001373	journal	December 2015
Stellarator design Boozer, Allen H. Journal of Plasma Physics, Vol. 81, Issue 6 https://doi.org/10.1017/s0022377815001373	journal	December 2015
Shear Alfvén continua in stellarators Spong, D. A.; Sanchez, R.; Weller, A. Physics of Plasmas, Vol. 10, Issue 8 https://doi.org/10.1063/1.1590316	journal	August 2003
Transport optimization in stellarators Mynick, H. E. Physics of Plasmas, Vol. 13, Issue 5 https://doi.org/10.1063/1.2177643	journal	May 2006
Reducing turbulent transport in toroidal configurations via shaping Mynick, H. E.; Pomphrey, N.; Xanthopoulos, P. Physics of Plasmas, Vol. 18, Issue 5 https://doi.org/10.1063/1.3560591	journal	May 2011
Comparing linear ion-temperature-gradient-driven mode stability of the National Compact Stellarator Experiment and a shaped tokamak Baumgaertel, J. A.; Hammett, G. W.; Mikkelsen, D. R. Physics of Plasmas, Vol. 20, Issue 2 https://doi.org/10.1063/1.4791657	journal	February 2013
Theory of runaway electrons in ITER: Equations, important parameters, and implications for mitigation Boozer, Allen H. Physics of Plasmas, Vol. 22, Issue 3 https://doi.org/10.1063/1.4913582	journal	March 2015
Efficient magnetic fields for supporting toroidal plasmas Landreman, Matt; Boozer, Allen H. Physics of Plasmas, Vol. 23, Issue 3 https://doi.org/10.1063/1.4943201	journal	March 2016
Physics optimization of stellarators Grieger, G.; Lotz, W.; Merkel, P. Physics of Fluids B: Plasma Physics, Vol. 4, Issue 7 https://doi.org/10.1063/1.860481	journal	March 1992
Guiding center drift equations Boozer, Allen H. Physics of Fluids, Vol. 23, Issue 5 https://doi.org/10.1063/1.863080	journal	January 1980
Transport and isomorphic equilibria Boozer, Allen H. Physics of Fluids, Vol. 26, Issue 2 https://doi.org/10.1063/1.864166	journal	January 1983
Evaluation of 1/ν neoclassical transport in stellarators Nemov, V. V.; Kasilov, S. V.; Kernbichler, W. Physics of Plasmas, Vol. 6, Issue 12 https://doi.org/10.1063/1.873749	journal	December 1999
Magnetohydrodynamics stability of compact stellarators Fu, G. Y.; Ku, L. P.; Cooper, W. A. Physics of Plasmas, Vol. 7, Issue 5 https://doi.org/10.1063/1.874002	journal	May 2000
Electron temperature gradient driven turbulence Jenko, F.; Dorland, W.; Kotschenreuther, M. Physics of Plasmas, Vol. 7, Issue 5 https://doi.org/10.1063/1.874014	journal	May 2000
Stability of a compact three-period stellarator with quasiaxial symmetry features Cooper, W. A. Physics of Plasmas, Vol. 7, Issue 6 https://doi.org/10.1063/1.874095	journal	June 2000
Use of the virtual-casing principle in calculating the containing magnetic field in toroidal plasma systems Shafranov, V. D.; Zakharov, L. E. Nuclear Fusion, Vol. 12, Issue 5 https://doi.org/10.1088/0029-5515/12/5/009	journal	September 1972
Finite- magnetic field line tracing for Helias configurations Strumberger, E. Nuclear Fusion, Vol. 37, Issue 1 https://doi.org/10.1088/0029-5515/37/1/I03	journal	January 1997
Finite- magnetic field line tracing for Helias configurations Strumberger, E. Nuclear Fusion, Vol. 37, Issue 1 https://doi.org/10.1088/0029-5515/37/1/i03	journal	January 1997
Pump plenum pressure dependence on divertor plasma parameters and magnetic geometry in the DIII-D tokamak Maingi, R.; Watkins, J. G.; Mahdavi, M. A. Nuclear Fusion, Vol. 39, Issue 9 https://doi.org/10.1088/0029-5515/39/9/311	journal	September 1999
Physics issues of compact drift optimized stellarators Spong, D. A.; Hirshman, S. P.; Berry, L. A. Nuclear Fusion, Vol. 41, Issue 6 https://doi.org/10.1088/0029-5515/41/6/305	journal	June 2001
PIES free boundary stellarator equilibria with improved initial conditions Drevlak, M.; Monticello, D.; Reiman, A. Nuclear Fusion, Vol. 45, Issue 7 https://doi.org/10.1088/0029-5515/45/7/022	journal	July 2005
Collisionless alpha -particle confinement in stellarators Lotz, W.; Merkel, P.; Nuhrenberg, J. Plasma Physics and Controlled Fusion, Vol. 34, Issue 6 https://doi.org/10.1088/0741-3335/34/6/010	journal	June 1992
The Plasma Boundary of Magnetic Fusion Devices Ghendrih, Philippe Plasma Physics and Controlled Fusion, Vol. 43, Issue 2 https://doi.org/10.1088/0741-3335/43/2/702	journal	January 2001
Comparison between stellarator and tokamak divertor transport Feng, Y.; Kobayashi, M.; Lunt, T. Plasma Physics and Controlled Fusion, Vol. 53, Issue 2 https://doi.org/10.1088/0741-3335/53/2/024009	journal	January 2011
Turbulent optimization of toroidal configurations Mynick, H.; Xanthopoulos, P.; Faber, B. Plasma Physics and Controlled Fusion, Vol. 56, Issue 9 https://doi.org/10.1088/0741-3335/56/9/094001	journal	August 2014
BEAMS3D Neutral Beam Injection Model McMillan, Matthew; Lazerson, Samuel A. Plasma Physics and Controlled Fusion, Vol. 56, Issue 9 https://doi.org/10.1088/0741-3335/56/9/095019	journal	July 2014
Mitigation of Alfvénic activity by 3D magnetic perturbations on NSTX Kramer, G. J.; Bortolon, A.; Ferraro, N. M. Plasma Physics and Controlled Fusion, Vol. 58, Issue 8 https://doi.org/10.1088/0741-3335/58/8/085003	journal	July 2016
An improved current potential method for fast computation of stellarator coil shapes Landreman, Matt Nuclear Fusion, Vol. 57, Issue 4 https://doi.org/10.1088/1741-4326/aa57d4	journal	February 2017
Optimizing Stellarators for Turbulent Transport Mynick, H. E.; Pomphrey, N.; Xanthopoulos, P. Physical Review Letters, Vol. 105, Issue 9 https://doi.org/10.1103/PhysRevLett.105.095004	journal	August 2010
Resilience of Quasi-Isodynamic Stellarators against Trapped-Particle Instabilities Proll, J. H. E.; Helander, P.; Connor, J. W. Physical Review Letters, Vol. 108, Issue 24 https://doi.org/10.1103/PhysRevLett.108.245002	journal	June 2012
Controlling Turbulence in Present and Future Stellarators Xanthopoulos, P.; Mynick, H. E.; Helander, P. Physical Review Letters, Vol. 113, Issue 15 https://doi.org/10.1103/PhysRevLett.113.155001	journal	October 2014
Intrinsic Turbulence Stabilization in a Stellarator Xanthopoulos, P.; Plunk, G. G.; Zocco, A. Physical Review X, Vol. 6, Issue 2 https://doi.org/10.1103/PhysRevX.6.021033	journal	June 2016
Optimizing Stellarators for Turbulent Transport Mynick, H. E.; Pomphrey, N.; Xanthopoulos, P. Physical Review Letters, Vol. 105, Issue 9 https://doi.org/10.1103/physrevlett.105.095004	journal	August 2010
Resilience of Quasi-Isodynamic Stellarators against Trapped-Particle Instabilities Proll, J. H. E.; Helander, P.; Connor, J. W. Physical Review Letters, Vol. 108, Issue 24 https://doi.org/10.1103/physrevlett.108.245002	journal	June 2012
Controlling Turbulence in Present and Future Stellarators Xanthopoulos, P.; Mynick, H. E.; Helander, P. Physical Review Letters, Vol. 113, Issue 15 https://doi.org/10.1103/physrevlett.113.155001	journal	October 2014
Intrinsic Turbulence Stabilization in a Stellarator Xanthopoulos, P.; Plunk, G. G.; Zocco, A. Physical Review X, Vol. 6, Issue 2 https://doi.org/10.1103/physrevx.6.021033	journal	June 2016
Design and Analysis of Divertor Scraper Elements for the W7-X Stellarator Lore, Jeremy D.; Andreeva, Tamara; Boscary, Jean IEEE Transactions on Plasma Science, Vol. 42, Issue 3 https://doi.org/10.1109/TPS.2014.2303649	journal	March 2014
Design and Analysis of Divertor Scraper Elements for the W7-X Stellarator Lore, Jeremy D.; Andreeva, Tamara; Boscary, Jean IEEE Transactions on Plasma Science, Vol. 42, Issue 3 https://doi.org/10.1109/tps.2014.2303649	journal	March 2014
Deblurring Images Hansen, Per Christian; Nagy, James G.; O'Leary, Dianne P. https://doi.org/10.1137/1.9780898718874	book	January 2006
Rank-Deficient and Discrete Ill-Posed Problems Hansen, Per Christian Mathematical Modeling and Computation https://doi.org/10.1137/1.9780898719697	book	January 1998
Near-Optimal Spectral Filtering and Error Estimation for Solving Ill-Posed Problems Taroudaki, Viktoria; O'Leary, Dianne P. SIAM Journal on Scientific Computing, Vol. 37, Issue 6 https://doi.org/10.1137/15M1019581	journal	January 2015
Near-Optimal Spectral Filtering and Error Estimation for Solving Ill-Posed Problems Taroudaki, Viktoria; O'Leary, Dianne P. SIAM Journal on Scientific Computing, Vol. 37, Issue 6 https://doi.org/10.1137/15m1019581	journal	January 2015
The Plasma Boundary of Magnetic Fusion Devices Stangeby, P. Series in Plasma Physics https://doi.org/10.1201/9781420033328	book	January 2000
Physics Design for ARIES-CS Ku, L. P.; Garabedian, P. R.; Lyon, J. Fusion Science and Technology, Vol. 54, Issue 3 https://doi.org/10.13182/FST08-A1899	journal	October 2008
The ARIES-CS Compact Stellarator Fusion Power Plant Najmabadi, F.; Raffray, A. R.; Abdel-Khalik, S. I. Fusion Science and Technology, Vol. 54, Issue 3 https://doi.org/10.13182/FST54-655	journal	October 2008
Designing ARIES-CS Compact Radial Build and Nuclear System: Neutronics, Shielding, and Activation El-Guebaly, L.; Wilson, P.; Henderson, D. Fusion Science and Technology, Vol. 54, Issue 3 https://doi.org/10.13182/FST54-747	journal	October 2008
Physics Design for ARIES-CS Ku, L. P.; Garabedian, P. R.; Lyon, J. Fusion Science and Technology, Vol. 54, Issue 3 https://doi.org/10.13182/fst08-a1899	journal	October 2008
The ARIES-CS Compact Stellarator Fusion Power Plant Najmabadi, F.; Raffray, A. R.; Abdel-Khalik, S. I. Fusion Science and Technology, Vol. 54, Issue 3 https://doi.org/10.13182/fst54-655	journal	October 2008
Designing ARIES-CS Compact Radial Build and Nuclear System: Neutronics, Shielding, and Activation El-Guebaly, L.; Wilson, P.; Henderson, D. Fusion Science and Technology, Vol. 54, Issue 3 https://doi.org/10.13182/fst54-747	journal	October 2008
Feasibility of U-curve method to select the regularization parameter for fluorescence diffuse optical tomography in phantom and small animal studies Chamorro-Servent, Judit; Aguirre, Juan; Ripoll, Jorge Optics Express, Vol. 19, Issue 12 https://doi.org/10.1364/OE.19.011490	journal	January 2011
Feasibility of U-curve method to select the regularization parameter for fluorescence diffuse optical tomography in phantom and small animal studies Chamorro-Servent, Judit; Aguirre, Juan; Ripoll, Jorge Optics Express, Vol. 19, Issue 12 https://doi.org/10.1364/oe.19.011490	journal	January 2011
Gyrokinetic Vlasov Code Including Full Three-dimensional Geometry of Experiments Nunami, Masanori; Watanabe, Tomo-Hiko; Sugama, Hideo Plasma and Fusion Research, Vol. 5 https://doi.org/10.1585/pfr.5.016	journal	January 2010
The Plasma Boundary of Magnetic Fusion Devices Stangeby, Peter C. Plasma Physics and Controlled Fusion, Vol. 43, Issue 2 https://doi.org/10.1887/0750305592	book	January 2000
Resilience of quasi-isodynamic stellarators against trapped-particle instabilities Proll, J. H. E.; Helander, P.; Connor, J. W. arXiv https://doi.org/10.48550/arxiv.1509.04185	text	January 2015

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