1 / 13

Examples of using Langevin equation to solve FP equation

Examples of using Langevin equation to solve FP equation. ASCOT Racetrack for tokamak particles. Ab initio particle loading Fusion alphas (thermonuclear, beam-target, beam-beam) NBI-generated ions Realistic orbit tracing Guiding center (4th order RK, w/ 5th order error check, fast)

phyre
Download Presentation

Examples of using Langevin equation to solve FP equation

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. Examples of using Langevin equation to solve FP equation

  2. ASCOT Racetrack for tokamak particles Ab initio particle loading • Fusion alphas (thermonuclear, beam-target, beam-beam) • NBI-generated ions Realistic orbit tracing • Guiding center (4th order RK, w/ 5th order error check, fast) • gyro orbit (Leap Frog, accurate, slow) Fully 3D • 3D magnetic field • 3D Wall Comprehensive interactions • Coulomb collisions • (Turbulent transport) • Models for relevant MHD: • NTM-type magnetic islands • Alfven Eigenmodes

  3. ASCOT4 Technical details Parallelization • MPI parallel testruns (HELIOS) with 16384 cores • Production runs with 4096 File I/O • Single process does all file I/O • HDF5 format, partly ASCII • Processing of data w/ MATLAB Magnetic field interpolation • PSPLINEs Programming approach • ASCOT completely rewritten in 2012-13 • Modular F90 • Only 2 libraries reguired: HDF5 & MPI

  4. Fusion alphas & iter 1st wall

  5. Axisymmetry vs ripple vs FIFusion alphas in 15MA scenario Ripple w/ FI’s Axisymmetric B field With bare ripple

  6. Original wall w/ 2 limiters Present wall design w/ poloidally extended ’continuous’ limiters Also wall shape matters...

  7. TBM mock-up exp’s at DIII-D

  8. Ripple map w/ and w/o TBM field bump Max field perturbation along separatrix close to 5% with TBM mock-up TF ripple TBM field bump BT φ Variation of the toroidal field • with the TBM coils • in the absence of TBM coils

  9. NBI-generated deuterons in DIII-D discharges w/ TBM mock-up limiters TBM mock-up coils

  10. Beam-target DD reaction T(1 MeV) Guiding-center following clearly not applicable  follow full gyro motion (FO integration)

  11. DD  DT  n (14 MeV) M. Schaffer & al, Nucl. Fusion 51 (2011) 103028 Experimental neutron flux in the TBM mock-up experiment Fraction of confined tritium in the plasma as calculated by ASCOT

  12. Impurity injection exp’s @AUG

  13. The case of missing 13C in AUG Besides fast ions, tritium retention is a hot issue for ITER  • Global impurity migration studies in AUG by injecting 13CH4 • post mortem analysis of samples from selected wall tiles -> 90% missing?? • Common assumption: axisymmetric 13C deposition • ASCOT simulation w/ a 3D wall and magnetic field: notable non-axisymmetry in 13C deposition (limiters, ICRH antennas, …) [J. Miettunen et al., NF 52 (2012) 032001]

More Related