DEGAS2

Contacts: Quinn Pratt

Short Description

Run the DEGAS2 neutral transport code with a fixed plasma background

Keywords

DEGAS2, Neutrals, Monte Carlo, Synthetic Diagnostics

Long Description

This module allows users to set up and run the DEGAS2 code with fixed 2D plasma background. The user provides a magnetic equilibrium (in the form of a gEQDSK file) and 1D kinetic profiles (as a .nc dataset). Custom 2D plasma backgrounds can also be provided. Then, each of the DEGAS2 setup executables (problemsetup, definegeometry2d, defineback, and tallysetup) are configured and run with a setup script. The core Monte Carlo neutrals simulation (flighttest) is run separately.

This OMFIT module parses the outputs of the DEGAS2 code to provide,

  • Scalars related to the neutrals: neutral density, pressure, emissivity of various lines (e.g. Balmer-alpha, Lyman-alpha, etc.)

  • Quantities related to transport: the source-rate of plasma ions (due to neutral ionization).

  • Flux-surface-averaged quantities.

  • Synthetic diagnostic outputs for detectors included in the particular build of DEGAS run by OMFIT. For example, on DIII-D this includes: MICER, CENS, LLAMA, ALPACA, Filterscopes, and MDS.

Typical workflows

Basic workflow,

  • User provides gEQDSK and input_profiles.nc.

  • Configure each DEGAS2 setup executable, e.g. specify number of flights, source strength, wall properties, etc.

  • Run the setup script.

  • Run the main flighttest program.

  • Postprocess profiles and detector outputs.

Supported Devices

  • DIII-D (omega cluster only).

Relevant publications

  • Stotler, Daren, and Charles Karney. “Neutral gas transport modeling with DEGAS 2.” Contributions to Plasma Physics 34.2‐3 (1994): 392-397.

Technical info

On the omega cluster, the DEGAS2 environment can be loaded with:

module purge
module load degas2

After running this, the setup script can be located: $DEGAS2_DIR/scripts/omfit_setup.py.

Contributors

List of contributors sorted by number of lines authored:

16359 Quinn Pratt
  114 Shaun Haskey

Users

List of usernames sorted by number of module imports: N/A