1 / 10

Princeton Plasma Physics Laboratory Highlights of Theory Accomplishments and Plans

Princeton Plasma Physics Laboratory Highlights of Theory Accomplishments and Plans. Department of Energy Budget Planning Meeting March 13-15, 2001. Selected Theory Research Highlights.

Download Presentation

Princeton Plasma Physics Laboratory Highlights of Theory Accomplishments and Plans

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Princeton Plasma Physics Laboratory Highlights of Theory Accomplishments and Plans Department of Energy Budget Planning Meeting March 13-15, 2001

  2. Selected Theory Research Highlights • MHD and Particle Codes Made Major Contributions to Stellarator Design: Optimization of Stability, Transport and Constructability. • Other Innovative Concepts also studied: Spherical Tori, Advanced Tokamaks, FRC. • Main Theory Groups: MHD (Jardin); Turbulence and Transport (Hahm); Waves/Energetic Particles (Cheng); Non-Axisym. Systems (Reiman); IFE & Non-MFE Plasma Science (Davidson); Laser-Plasma Interactions (Valeo) • Lead role in successfully establishing Plasma Science Advanced Computing Institute (PSACI). PPPL has helped establish stature/visibility of Plasma Science in Advanced Scientific Computing community. • Energetic particles: theory of RF-driven rotation.

  3. Examples of “Experiment/Theory” Collaborations • Experiment/Theory investigations of shear-flow suppression of turbulent transport [K. Burrell (DIII-D) with T. S. Hahm] • ICRF-induced rotation and ripple loss in Tore Supra [X. Garbet, et al. (Cadarache) with R. White] • Collaborative development of RWM analysis capability for DIII-D with GA & Columbia U. [M. Chance -- @ GA for one year] • Highly productive collaborations on international facilities (JET, JT60U, LHD, ASDEX, ..) addressing Turbulent Transport (Rewoldt, Hammett); MHD (Manickam, Monticello); Energetic Particles (Cheng, Gorelenkov, White); Boundary Physics (Stotler).

  4. Selected Technical Milestones for FY 2002 • Obtain technical results from nonlinear gyrokinetic full torus code (GTC) including electron dynamics (September, 02). • Compare DEGAS2 modeling results with analysis of experiments with lithium surfaces (September, 02). • Compare measured parametric dependencies of fluxes in NSTX with gyrokinetic-continuum and/or gyrofluid codes (September, 02). • Complete implementation of “virtual fluctuation” diagnostics in gyrokinetic, gyrofluid/GK-continuum nonlinear turbulence simulations (September, 02).

  5. Selected Technical Milestones for FY 2003 • Obtain GTC simulation results for the generation and damping of zonal flows in stellarators to elucidate the effects due to the lack of a symmetry direction (September, 03). • Improve the NOVA-K code to include the effects of plasma flow and pressure anisotropy for tokamaks (September, 03). • Compare measured fluctuation spectra in NSTX core with predictions from nonlinear gyrokinetic and/or gyrofluid/GK-continuum codes using “virtual diagnostics” developed in FY02 (September, 03). • Provide capability for realistic simulation of a nonlinear resistive MHD disruptions for NSTX (September, 03).

  6. Microturbulence & Transport Highlights • 3D Global Gyrokinetic Particle Simulation of Collisional Damping of Zonal Flow and Size Scaling (Lin et.al.) • bursting behavior seen in experiments • interplay between turbulence, flow damping and collisions • Simulation of Shear Alfven Waves in Gyrokinetic Plasmas • Split-Weight df Scheme (Lee et al.) • Hybrid Scheme w/ kinetic closure (Lin and Chen) • Other algorithmic improvements • Enhanced GTC: Self-consistent Radial Electric Field for neoclassical transport in 3-D Stellarators (Lewandowski et al.)

  7. Progress in Stellarator Theory • New optimizer uses PIES code to heal magnetic islands in 3D configurations. New numerical diagnostic for accurate measurement of small changes in island widths. • Optimized physics design identified for NCSX, considering wide range of physical effects.New design has 50% better neoclassical confinement, simpler coils with lower current density, improved flux surface quality. • Code for designing stellarator coils that preserve finite-b equilibrium flux surfaces developed & applied to NCSX design • Flexibility and robustness studies have explored ability of proposed NCSX coils to produce stable plasma configurations with good quasi-axisymmetry for variety of current and pressure profiles.

  8. Stellarator Theory Plans • Documentation for NCSX Physics Validation Review (end of March) • Incremental improvements in physics properties and flexibility of NCSX configuration thereafter. • GTC code modifications to allow drift wave simulations in stellarator geometry. • PIES calculations of neoclassical effects on stellarator island formation to be initiated. • Global optimization scheme being developed circumvents problem of trapping in local maxima of target function. • Improved optimizer will enhance capability for making configuration improvements. • Will also be applied in free-boundary optimizer to design experiments for addressing key physics issues.

  9. Energetic Particle Physics Highlights • TAEs can be highly unstable in NSTX and fast ion loss due to TAEs can be large and comparable to prompt losses. • Two new types of TAE modes were observed with frequency chirping and are identified as Resonant TAE modes (R-TAE). • Ballooning modes can be stabilized by kinetic effects of trapped electrons finite ion Larmor radii in NSTX with the critical beta enhanced by at least a factor of 5 over MHD values. • Energetic circulating ions are found to have a stabilizing effects on fishbone modes at high beta in spherical tori. • Transport of energetic ions during relaxation oscillations in spherical tokamaks depends on beta. • Nonlinear simulations of fishbone using the MH3D-K code showed MHD nonlinearity to be as important as particle nonlinearity. • Theory to explain observed plasma rotation during ion cyclotron heating even though this heating process introduces negligible angular momentum.

  10. OTHER PPPL THEORY RESEARCH AREAS • Wave-Particle Interactions (Energetic Particles) -- e.g, seminal contributions such as TAE with strong theory/exp. Impact • Boundary Physics (Neutrals Modeling) -- e.g., DEGAS-2 as powerful new tool for divertor/edge analysis with excellent MPP compatibility • PPPL Theory plays key role in Heavy Ion Fusion Virtual National Laboratory (HIF-VNL) with LBNL and LLNL. • lead positions in HIF-VNL: Deputy Director (R. Davidson) & Deputy Head of Theory & Modeling (W. Lee) • Advanced analytical and numerical modeling of intense beam propagation and beam-plasma interaction • Laser-Plasma Interactions -- for ICF & Plasma-based Accelerators {Presidential Early Career Award for Scientists & Engineers to G. Shvets, April 11, 2000}

More Related