Science Working Groups (2021-2022)

  1. Core-Pedestal Confinement and Transport (Objective 1) - W. Guttenfelder

  1. Transport & pedestal structure: W. Guttenfelder

    1. R(21-1):  ST pedestal transport modeling using gyrokinetics

    2. Effect of low collisionality

    3. Effect of wall conditioning

  1. Heating and Current Drive: M. Podesta

    1. R(21-3): Optimization of NBI mix for AE-mitigated scenarios

    2. NBI Characterization

    3. Validate NB deposition current drive models

    4. HHFW coupling physics: SOL loss physics

  1. Steady state physics (Objective 2) - R. Raman

    1. Macrostability: Demonstrate high-β, low-li discharges at low disruptivity: J. Berkery

      1. R(21-2):  Prepare tools for commissioning

      2. Characterization of error fields/locked modes, develop EF mitigation

      3. Mitigation of internal MHD (TMs, NTMs)

      4. Kinetic stabilization of RWM at low collisionality: real-time control

      5. Develop real-time disruption prediction and avoidance

  1. Scenarios and Real-time control: Establish and optimize high non-inductive fraction operation; Particle control and heat flux mitigation necessary for stationary discharges: D. Battaglia

    1. R(21-2):  Prepare tools for commissioning

    2. Start-up/Ramp-up scenarios

      1. Error field mitigation - use

      2. Real-time control at high shaping

      3. HHFW

    3. Particle control - use

      1. Effect of wall conditioning

      2. Effect of fueling

      3. ELM-free, small-ELM candidates

      4. Real-time control

  1. Boundary & exhaust physics (Objective 3) - Vlad Soukhanovskii

    1. Power exhaust: Assess performance and lifetime of new NSTX-U PFCs, and establish the physics and engineering basis to enable future PFC/divertor upgrade; Develop and evaluate power exhaust techniques for mitigating high projected NSTX-U heat fluxes - K. Gan (UTenn-Knoxville)

      1. Power exhaust and control: 

        1. Characteristics of new tiles

        2. Model validation (HEAT)

        3. SF divertors, target incidence w/r-t f/b control

        4. Attractive radiative core/divertor scenarios

        5. Impact of 3D perturbations

      2. SOL heat flux width

  1. Particle control and PMI: Investigate the sustainability of particle exhaust and PMI control via lithium pumping for density and impurity control consistent with integrated scenarios - E. Unterberg (ORNL) 

    1. Particle control - develop and understand (Overlap with 2.b.III)

      1. Effect of wall conditioning

      2. Effect of fueling

      3. ELM-free, small-ELM candidates

      4. Real-time control

  1. ELM stability and control: Develop and understand techniques to mitigate/eliminate edge transients and the associated enhancement of PMI - A. Kleiner

    1. R(21-4): ST pedestal stability modeling and determination of stability thresholds associated with ELMs

    2. ELM-free and mitigated regimes

Black: Research directed towards experimental operations

Red: Research Milestone work