Transport predictions with TRANSP

TRANSP can be run in interpretive or in predictive mode. In the former operation, the kinetic profiles are input to TRANSP, which calculates transport diffusivities. In predictive mode, it evolves one or more kinetic profiles using a predictive turbulence transport model.

LPREDICTIVE_MODE=0

Use this option to use TRANSP in interpretive mode.

LPREDICTIVE_MODE=3

Use this option to use TRANSP in predictive mode, or to switch from interpretive to predictive mode during the simulation. This flag is compatible with interpretive simulations, if all the predictive LPREDICT_XXX options are set to zero.

Transport predictions in TRANSP are handled by the pt-solver transport solver, developed by Xingqiu Yuan.

LPREDICTIVE_MODE=5

Use this option to use TRANSP in predictive mode, or to switch from interpretive to predictive mode during the simulation. This flag is compatible with interpretive simulations, if all the predictive LPREDICT_XXX options are set to zero.

Transport predictions in TRANSP are handled by the t3d solver, developed by Tony Qian, Noah Mandell, Bill Dorland, Jai Sachdev.

The following models for turbulence core transport predictions are available in TRANSP.

• Current Diffusive Ballooning Mode model (CDBM)
• mixed Bohm-gyro Bohm model
• Coppi-Tang model
• TGLF
• Multi-Mode model
• User model
• GLF23
• Rebout-Laila-Watkins model

Important changes - February 2022

To improve transparency and simplify the TRANSP namelist, all input parameters associated with specific turbulence transport models have been removed from the TRANSP namelist. At this time, separate namelists are available for GLF23, MMM, NEO, TGLF. After selecting their favorite transport model in pt-solver, users need to specify the path to a namelist they wish to use, using the following flag xxxx_TEMPLATE='path to the namelist that you wish to use', where xxxx should be replaced by one of the available code options, e.g. MMM_TEMPLATE.

If you do not have a template at hand, please do the following:

• Run TRDAT as usual
• remove from the TRANSP namelist any variable that TRDAT indicates as obsolete or not available
• When TRANSP completes without errors, you will see a new file in your workspace, with name <runID>_xxx.nml, where xxx is the model that you have selected.
• Copy this file and make changes to the template as needed
• Add the following line to your TRDAT namelist: xxx_TEMPLATE='path to your template'
• run TRDAT again. This time the <runID>_xxx.nml file should the same as your modified template
• Submit TRANSP as usual.