TRANSP Namelists, general settings

NSHOT

The shot number to be simulated.

Time Control

TINIT

The start time of the simulation.

FTIME

The end time of the simulation.

TRDAT interpolates UFILE data onto two fixed time grids covering the period between TINIT and FTIME, these grids are specified using the following two namelist variables:

TGRID1

The spacing between time points for scalar input data

TGRID2

The spacing between time points for profile input data

These entries control the time resolution of the input data as TRANSP sees it. The main code will then interpolate to intermediate time points as required.

TRANSP has a hierarchy of different timesteps for the different physical processes, which are - from the longest ot the shortest - sources, magnetic equilibrium and transport. The time step for the sources is provided by the user, either in the namelist or from a UFILE PREDTS/EXTDTS.

IMPORTANT: TRANSP uses the saem time step for ALL sources. If multiple sources are present in the simulation, make sure that the time steps for individual sources are consistent.

The equilibrium and transport time step are adjusted by the solvers to ensure convergence. The following parameters control the variation and initialisation of the different time steps used:

DTTOR

Time step for the Electron Cyclotron sources

DTICRF

Time step for the Ion Cyclotron sources

DTLH

Time step for the Lower Hybrid sources

DTBEAM

Time step for the Neutral Beam sources

DTMING, DTMAXG

Minimum and Maximum allowed time steps for the advance of the MHD equilibrium. Note that all other timesteps are constrained by DTMAXG and so this must be at least MAX( DTMINT, DTMINB ). DTMAXG is used as the initial value of the equilibrium timestep but the eventual value used will be determined by macroscopic properties of the equilibrium or input boundary.

DTMINT, DTMAXT, DTINIT

Minimum, Maximum and Initial time step to use for the solution of the heat and particle balance equations. The actual step size used is controlled by changes in the temperature or density.

DTMINB, DTMAXB, DTINIB

Minimum, Maximum and Initial time step to use for the solution of the Poloidal Field Diffusion Euqation.

Note on the choice of time step

Regardless of the value for individual sources, TRANSP uses one single value for all sources.
If NLBEAM=.T., the time step is set by DTBEAM.
If NLBEAM=.F. and NLICRF=.T., the time step is set by max(DTMAXG,DTICRF).
THe maximum time step for the equilibrium calculations is independent of the source time step, except for ICRF, and can be set smaller than the source time step.

Radial Resolution

NZONES

The number of radial zones used when solving the 1D particle and heat balance equations. This is usually set to 50 but can be changed depending on memory and time constraints.

NZONES_NB

The number of radial zones used in the Neutral Beam Monte Carlo module (NUBEAM). 20 zones is recommended or 60 zones with smoothing.

NZONES_FP

The number of radial zones used in the fast ion Fokker-Planck model (20 zones recommended with default 'dxfsmoo' smoothing).

NZONES_FB

The number of radial zones used when evaluating fast ion effects such as beam-beam interactions. Effectively the number of radial zones used in the fast ion distribution function for these cases. Note that NZONES/NZONE_FB, NZONES_NB/NZONE_FB and NZONES_FP/NZONE_FB must all be integers.

Output Control

The following two variables control when TRANSP outputs data:

SEDIT

This sets the time period between successive output of profile data

STEDIT

This sets the time period between successive output of scalar data

Fast Particle Output, RF output

Obtaining the fast particle distribution involves utilising TRANSP capability to output ASCII Compressed Files (ACFILES). This allows outputing of all or part of TRANSP COMMON to a file. The settings for this are as follows:

SELOUT

A list of variable names to be written to the output ASCII file. By default this is all of them (preferred).

SELAVG

A subset of the above variables to be averaged prior to being output. By default none are averaged. For Fast particle output select 'FBM BMVOL BDENS2 EBA2PL EBA2PP'

OUTTIM

An ascending list of times when the ACFILES should be written. A maximum of 99 can be written. The output files are named 'runID'.DATA1 for OUTTIM(1), 'runID'.DATA2 for OUTTIM(2) etc.

AVGTIM

This is the averaging time in seconds used for the variables specified in SELAVG. The variables are averaged over the period AVGTIM prior to a particular OUTTIM. Note that the times specified for OUTTIM must be separated by at least AVGTIM.

MTHDAVG

The averaging method to be used. 1 is the default option, set to 2 to sample variables after each heating source timestep and set to 3 to use a sample period specified by AVGSAMP.

AVGSAMP

The averaging method to be used. 1 is the default option, set to 2 to sample variables after each heating source timestep and set to 3 to use a sample period specified by AVGSAMP.

Field Orientation

NLBCCW

Set this to TRUE [FALSE]if the toroidal magnetic field is counter-clockwise [clockwise] when viewed from above

NLJCCW

Set this to TRUE [FALSE]if the toroidal magnetic field is counter-clockwise [clockwise] when viewed from above

IMPORTANT: Make sure that the value set here is consistent with the value set in the UFILES PREMMX/EXTMMX, PREQPR/EXTQPR. The value of NLJCCW is used by NUBEAM, TORAY and GENRAY to adjust the current drive, but the equilibrium solver is always taking the sign from the UFILES. NLJCCW and NLBCCW do not overwrite the sign settings in the UFILES.

MPI Settings

Several components of TRANSP have been parallelised and consequently when a parallel job is submitted the user can specify whether each of these components is run in serial or in parallel. Set the following flags to 1 for parallel runs, set = 0 for serial runs.

NBI_PSERVE

flag for parallel run with NUBEAM

NTORIC_PSERVE

Flag for parallel runs with TORIC

NGENRAY_PSERVE

Flag for parallel runs with GENRAY

NCQL_PSERVE

Flag for parallel runs with CQL3D

NPTCL_PSERVE

Flag for parallel runs with PT-SOLVER (typically for TGLF)