Proceedings of ITC/ISHW2007

Data Structure for LHD Plasmas in the International
Stellarator/Heliotron Proﬁle Database
Hisamichi FUNABA1) , Andreas DINKLAGE2) , Hiroshi YAMADA1) , Masayuki YOKOYAMA1) ,Kiyomasa WATANABE1) , Kazumichi NARIHARA1) , Ichihiro YAMADA1) ,Kenji TANAKA1) , Tokihiko TOKUZAWA1) , Sadayoshi MURAKAMI3) , Masaki OSAKABE1) ,Kazuo KAWAHATA1) and the LHD Experimental Group1)1)2)National Institute for Fusion Science, Toki, Japan
Max-Planck-Institut für Plasmaphysik, EURATOM-Association, Greifswald, Germany
3)
Department of Nuclear Engineering, Kyoto University, Kyoto, JapanThe 2D-UFILEs are created from the experimental data of the Large Helical Device for the International
Stellarator/Heliotron Prioﬂe Database (ISHPDB). The data which were already published will be collected andopened to public on some WWW servers. The directory structure for the WWW server of ISHPDB is designed.
Keywords: stellarator, heliotron, proﬁle database, UFILE, core electron-root conﬁnement
1. Introduction
The International Stellarator/Heliotron ProﬁleDatabase (ISHPDB) activity has been started as the extension of the International Stellarator/Heliotron Conﬁnement
Database (ISHCDB) [1] . This activity is intended tocompare various physical phenomena which may becommonly observed among several stellarator/heliotron
devices, such as the Large Helical Device (LHD), W7-AS,
TJ-II, Heliotron J, CHS, HSX, H-1 and so on. For example,
with respect to the features of CERC (Core Electron-RootConﬁnement) in helical plasmas are investigated in ref.
[2]. The data which will be included in the ISHPDB
database should be limited as the already published datain principle. In the case of LHD, the data for CERC were
published in ref. [3].
The database will be developed in the following twosteps: (1) collection and open to public of data ﬁlesin the text format on the WWW servers for ISHCDB (http://iscdb.nifs.ac.jp/ on NIFS site). (2) detailed databasewhich has ability of search and so on [4]. In this paper, theoutline of the step 1 is introduced. The format and actual
contents of the proﬁle database are described in section 2.
In Section 3, the structure of the directories is shown. A
summary is provided in Section 4.

2. The format and contents of the proﬁle databaseAt ﬁrst, collection of text ﬁles has been started for
ISHPDB. As for the data format of the LHD data, theUFILE format, which is adopted in the ITER proﬁledatabase [5] is chosen. The data from the proﬁle database
will be used as the input ﬁle for transport codes. This
UFILE format is also adopted for the input data form forauthor’s e-mail: funaba@lhd.nifs.ac.jp

the integrated simulation system for helical plasmas [6]which is an extension of the 1-dimensional transport code
TASK (Transport Analyzing System for tokamaK) [7] tohelical plasmas.
The proﬁle data, such as the electron temperature, T e ,the ion temperature, T i , the electron density, ne , the radiation loss, Prad and so on are derived based on the experimentally measured data. The proﬁles which are evaluatedby some codes are also included such as the deposition
power of NBI (Neutral Beam Injector) to electrons, PeNBI ,and ions, PiNBI , the density of fast ions, nfast , the particle
esource from NBI, S NBI, the absorbed power of ECH (Electron Cyclotron Resonance Heating), PECH , and so on.
Figure 1 shows an example 2D-UFILE, which includes a proﬁle of T e data. This example is taken fromthe database of the CERC plasmas. The informations of
the device, date, the independent variable labels, the dependent variable label and the number of data are written
in the ﬁrst 9 lines. The data of the 51 positions of the normalized average minor radius, ρ, are shown at the top of
the data section. In this ﬁle, the T e data at one timing oft = 2.003 sec. are shown. This timing information follows
to the ρ data. The last 11 lines of the data section represent the T e data. The comment lines are located at the lastposition.
The normalized average minor radius, ρ = (Φ/Φa )1/2 ,(Φ : toroidal magnetic ﬂux) is derived from a magnetic
ﬂux surface data, which is selected based on the symmetry of the electron temperature proﬁle. The name ofthe selected magnetic ﬂux surface ﬁle is registered in thecomment section of the UFILE. In this case, the ﬁle ’lhdr375q100b016a2020.ﬂx’ was chosen. Many magnetic ﬂux
surface ﬁles were prepared in advance by using VMEC [8]or HINT2 [9] codes. The most suitable data is selectedProceedings of ITC/ISHW2007

Fig. 2 An example of 2D-UFILE of PeNBI .

Fig. 1 An example of 2D-UFILE of T e .

among them based on the T e proﬁle. The T e proﬁle arederived by ﬁtting the experimental data by using a certain
function.
The data ﬁle of 2D-UFILE is named like’lhd 032940 002003 2d.dat’, where the discharge number
and the timing informations are included. When the2D-UFILE contains the time evolution data, it becomes’lhd 032940 2d.dat’.
The proﬁles of PeNBI and PiNBI are calculated by a threedimensional Monte Carlo simulation code [10]. Figure 2shows an example of the UFILE for PeNBI . QNBIE means
the NBI heating power to electrons. This data is calculated by a set of codes of HFREYA, MCNBI and FIT. The
comment ’PNBI = PFIT’ means that the calculation result
is used for the total amount of the NBI deposition power,
which Zeﬀ largely aﬀects.
The standard set of variables of 2D-UFILE includes
some geometry informations, such as the normalized average minor radius, ρ, the geometric major radius, R, thegeometric minor radius, r, the volume, V, the magnetic
ﬁeld strength, B, the elongation of the magnetic surface,
κ, the geometric quantities, h|∇ρ|i and h|∇ρ|2 i, and so on.
It is important to make clear deﬁnition of them especiallyfor the high β plasmas on LHD. In order to construct thedatabase which includes data from several diﬀerent devices, they should be commonly deﬁned or at least theirdeﬁnition should be clearly documented when the data areregistered.
More informations are needed to be included in the ISPDB server with respect to developing the database, suchas the change of diagnostic analysis (calibration, abel con-version process, ...), the conversion from the real coordinate to ρ, revision of the equilibrium data, selection of theequilibrium data and so on. The assumptions which areused in deriving the proﬁles should be obviously described.
For example, another assumption for the NBI power depodep
depbirthsition of Pdep
NBI = PNBI FIT × PNBI exp /PNBI FIT is also used.
3. Structure of the directories
In this section, the directory structure for ISHPDB
which is planned in order to open to public on a WWW
server is described. Figure 3 shows an example of thedirectory structure for ISHPDB. Four directories are contained in the directory with the device name, e.g. ’LHD’.
The contents of each directory are as follows.
(1) The ’data’ directory includes the UFILEs of 2D, 1D,
0D. The time development of the data and the general information of the discharge should also be included. Thisdirectory is divided into the directories with the shot number.
(2) The ’conﬁg’ directory includes the magnetic ﬂux surface data for the mapping.
(3) The ’topics’ directory includes the list of shot numbers
and timings for each topics. This list will have the namelike ’lhd cerc 2006.lst’ etc.
(4) The ’analysis’ directory will contain the results oftransport analysis and so on.

4. Summary
Making of the proﬁle data of LHD for ISHPDB has
been started. The 0D- and 2D-UFILEs from the LHD data
are created for the registration of the ISHPDB. The deﬁnitions and assumptions in making these ﬁles are expressedin the comment lines. In order to construct the databasewhich includes data from several diﬀerent devices, the in-Proceedings of ITC/ISHW2007

Fig. 3 Structure of directories for ISHPDB.

formations (especially the geometry informations) should
be commonly deﬁned or at least their deﬁnition should beclearly documented when the data are registered. The directory structure for the WWW server of ISHPDB is also
designed.
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