Automated divertor target design by adjoint shape sensitivity analysis and a one-shot method

Reiter, D.; Baelmans, M.

doi:10.1016/J.JCP.2014.08.023

Title: Automated divertor target design by adjoint shape sensitivity analysis and a one-shot method

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Abstract

As magnetic confinement fusion progresses towards the development of first reactor-scale devices, computational tokamak divertor design is a topic of high priority. Presently, edge plasma codes are used in a forward approach, where magnetic field and divertor geometry are manually adjusted to meet design requirements. Due to the complex edge plasma flows and large number of design variables, this method is computationally very demanding. On the other hand, efficient optimization-based design strategies have been developed in computational aerodynamics and fluid mechanics. Such an optimization approach to divertor target shape design is elaborated in the present paper. A general formulation of the design problems is given, and conditions characterizing the optimal designs are formulated. Using a continuous adjoint framework, design sensitivities can be computed at a cost of only two edge plasma simulations, independent of the number of design variables. Furthermore, by using a one-shot method the entire optimization problem can be solved at an equivalent cost of only a few forward simulations. The methodology is applied to target shape design for uniform power load, in simplified edge plasma geometry.

Authors:

Reiter, D. ^[1]; Baelmans, M. ^[2]

Institute of Energy and Climate Research IEK-4, Forschungszentrum Juelich GmbH, EURATOM Association, Trilateral Euregio Cluster, D-52425 Juelich (Germany)
KU Leuven, Department of Mechanical Engineering, Celestijnenlaan 300A, 3001, Leuven (Belgium)

Publication Date:: Mon Dec 01 00:00:00 EST 2014

OSTI Identifier:: 22382146

Resource Type:: Journal Article

Journal Name:: Journal of Computational Physics

Additional Journal Information:: Journal Volume: 278; Other Information: Copyright (c) 2014 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 0021-9991

Country of Publication:: United States

Language:: English

Subject:: 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; AERODYNAMICS; DESIGN; DIVERTORS; EDGE LOCALIZED MODES; MAGNETIC CONFINEMENT; MAGNETIC FIELDS; OPTIMIZATION; PLASMA; PLASMA SIMULATION; SENSITIVITY ANALYSIS; TOKAMAK DEVICES

Citation Formats


                    Dekeyser, W., E-mail: Wouter.Dekeyser@kuleuven.be, Reiter, D., and Baelmans, M. Automated divertor target design by adjoint shape sensitivity analysis and a one-shot method.  United States: N. p., 2014. 
        Web.  doi:10.1016/J.JCP.2014.08.023.

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                    Dekeyser, W., E-mail: Wouter.Dekeyser@kuleuven.be, Reiter, D., & Baelmans, M. Automated divertor target design by adjoint shape sensitivity analysis and a one-shot method.  United States.  https://doi.org/10.1016/J.JCP.2014.08.023

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                    Dekeyser, W., E-mail: Wouter.Dekeyser@kuleuven.be, Reiter, D., and Baelmans, M. 2014.  
        "Automated divertor target design by adjoint shape sensitivity analysis and a one-shot method".  United States.  https://doi.org/10.1016/J.JCP.2014.08.023.

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@article{osti_22382146,

  title        = {Automated divertor target design by adjoint shape sensitivity analysis and a one-shot method},

  author       = {Dekeyser, W., E-mail: Wouter.Dekeyser@kuleuven.be and Reiter, D. and Baelmans, M.},

  abstractNote = {As magnetic confinement fusion progresses towards the development of first reactor-scale devices, computational tokamak divertor design is a topic of high priority. Presently, edge plasma codes are used in a forward approach, where magnetic field and divertor geometry are manually adjusted to meet design requirements. Due to the complex edge plasma flows and large number of design variables, this method is computationally very demanding. On the other hand, efficient optimization-based design strategies have been developed in computational aerodynamics and fluid mechanics. Such an optimization approach to divertor target shape design is elaborated in the present paper. A general formulation of the design problems is given, and conditions characterizing the optimal designs are formulated. Using a continuous adjoint framework, design sensitivities can be computed at a cost of only two edge plasma simulations, independent of the number of design variables. Furthermore, by using a one-shot method the entire optimization problem can be solved at an equivalent cost of only a few forward simulations. The methodology is applied to target shape design for uniform power load, in simplified edge plasma geometry.},

  doi          = {10.1016/J.JCP.2014.08.023},

  url          = {https://www.osti.gov/biblio/22382146},
  journal      = {Journal of Computational Physics},

  issn         = {0021-9991},

  number       = ,

  volume       = 278,

  place        = {United States},

  year         = {Mon Dec 01 00:00:00 EST 2014},

  month        = {Mon Dec 01 00:00:00 EST 2014}

}

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