TrICH

15-Sep-2009
07-Dec-2009

Trich is a utility to prepare ICRH heating data for Transp, and replaces icrhlist. It will combine antenna which operate at nearly the same frequency throughout the pulse - this can significantly reduce the run time when using the Toric RF code. It also includes Iter Like Antenna ( ILA ) data when available ( Log Output )

Running the Program

TrICH is located in ~pshare/bin, which is on the path set up for Transp windows. The command

> TrICH -P 72505 -R JETPPF -W tranppf Fcut 1.0% { -F 72505X01TR.DAT }

reads ICRH data ( RFA, RFB ..RFE ) from JETPPF, and writes the TICH DDA under UID $USER.  Antenna with the same phasing which differ by less than 1% in frequency are combined ( in this case  A&B, C&D to give only 2 antenna and 50% less CPU ). Fcut is the % difference in frequency allowed, which defaults to 1.5%. This value will combine all antenna with the same nominal frequency, which is acceptable for any runs not intended as detailed RF heating studies.( With the current RF configuration, A&B always combine as they are driven by the same generator ) The cut frequency cut may be defined in MHz, by ommitting the % sign.

Running with JETtransp

If the DDA TICH exists, & the environment variable $TRICH_SKIP is set ( which it is by default ), then TrICH will not be rerun

To force TrICH to rerun, with a different cut ( eg 0.5% ) -

>unsetenv TRICH_SKIP
>setenv TRICH_FCUT 0.5%

before running JETtransp.

ILA status

TrICH will also read IterLike Antenna data from the RFE datatype. The strap phasing is always set to dipole, which is believed to be correct for all data currently availabe ( to start of C27 )

TR.DAT

It is necessary  to change TR.DAT , to reflect the different number of antenna, and the different DDAs. If the namelist is available to TrICH, these changes will be made automatically. If not, the required changes are written to the log file.

The  PICH, FREQ definitions are replaced with

PRERFP='TICH'
EXTRFP='PWRF PPF:tranppf'
PRERFF='TICH'
EXTRFF='FQRF PPF:tranppf'

and NICHA, the number of antenna, may also be varied ( see Antenna phasing section below )

Ufile antenna geometry

Specification of the antenna geometry has been automated ( to an extent ) from version JET_47.  Ufiles RFA72584.A2, .ILU, .ILL specify the geometry for the A2, & IterLike ( upper & lower ) antennae. This data is not shot dependent - to use the data, add links RFA<shot>.<antenna> to the transp data directory ( $TDD ) which target the standard Ufiles in $DATADIR/JET.  ( This will be done by JETtransp, if RF analysis is requested ). The RFA data is made available by adding cards

NGEOANT = -211
PRERFA= 'RFAG' 'RFAG' 'RFAG'
EXTRFA(1) = 'A2'
EXTRFA(2) = 'ILU'
EXTRFA(3) = 'ILL'

The -ve value of NGEOANT indicats that the geometry is provided in the RFAG Ufiles. Each digit indicates the geometry associated with the vectors stored in the RFP ufiles - in this case, A2, A2, ILU. See the Transp Helpfile for further information.

NB the A2 geometry in common use is believed to be incorrect - see this report. The values stored in RFAG..A2 correspond to the position specified on the TF-H website.

Antenna Phasing

If the antenna geometry is defined in Ufiles, then it is essential that NNPHI values are provided for all antenna - the approximate calculation of NNPHI in trdat is not supported in this mode of operation. Note also that if NNPHI was defined, the definitions may need to be altered, if the number of antenna has been reduced ( by combining those with the same frequency ) The user is responsible for ensuring the correct values of NNPHI are provided. Weights and values for common RF configurations may be fond in the Toric webpages

Legacy runs

An exception is made for reprocessing Legacy runs ( for backwards compatibility ) If

then TrICH operates in 'Legacy' mode, and

  1. the matching of antenna with the same frequency will be skipped.
  2. the previous antenna geometry definition is retained, the RFAG definitions are not added to the namelist

Under these circumstances, the old ( & deprecated ) approximate calculation of NNPHI will still work.

Example

TrICH writes a summary of the new geometry at the end of the log file ( >tail -n 22 $TWD/TrICH.log ) :

 write_trdat_list -I- /common/transp_shared/Data/work/jconboy/JETRF/78136J02
                      /78136J02TR.DAT written, status 0

>>> No of antenna reset from 2 to 3 !! <<<< 
>>> NPHI, NUM_NPHI must now be set for all antenna 

TrICH - Antenna grouping for 78136 

Gp Type Antenna Available Phasing
1: A2   A B       F F T T 1000.0 1000.0 -90.0 90.0
2: A2       C D   T T T T  -90.0   90.0 -90.0 90.0
3: IL   U 
jD_close_PPF -I- Closed PPF shot 78136 Seq 72 Program TrICH Vn 100