Test case for DTT (2019)

DTT, the Divertor Tokamak Test facility, is the new plasma physics research device under construction in Italy, which will benefit from a substantial support from EUROfusion to specifically address the problem of heating and power exhaust in ITER and DEMO devices. DTT characteristic parameters are: toroidal field B_0 = 6.0T, major radius R_0 = 2.08m, aspect ratio A ≈ 3.2, plasma current I_p=5.5 MA, additional power P_Tot=45 MW.

In this page the equilibrium and plasma parameters for the Single Null (SN) original baseline scenario (2018) will be given.

• The original Single Null (SN) "engineering" equilibrium (version v1, at the beginning of the flat-top (t=36s), beta_poloidal=0.43, internal inductance li=0.895), generated using the CREATE-NL code (Albanese R. et al 2003 ISEM 2003 (Versailles, France); Albanese R. et al 2004 Nucl. Fusion 44 999), has been used as input for the high-resolution code CHEASE (H. Lütjens et al., Computer Physics Communications 97 (1996) 219-260), in order to "smooth" the original last closed magnetic surface (LCMS) corresponding to the separatrix: as a matter of fact, CHEASE and several linear stability MHD codes (as well as hybrid MHD-Gyrokinetic codes) can not consider diverted equilibria. A graphic output (please, ignore the "poloidal beta" plots which are wrong!) of the equilibrium is given here
  ( Equil_DTT_SN_v1_Ipl_5d5MA_R0_2d08_betap_0d43_li_0d895_t_at_36s_ref_mesh_pchease_tensbnd=-300.0.pdf).



• The corresponding EQDSK file can be found here, EQDSK_COCOS_02_POS.OUT.
• The bulk ion density, required, e.g., in the single fluid MHD momentum equation, has been obtained by a METIS (J.F. Artaud et al 2018 Nucl. Fusion 58 105001) run; the values given by METIS for the electron density n_e, temperature T_e, bulk ion temperature T_i and safety factor q as function of the normalized toroidal flux tho_tor, can be found here, DTT_R208_fullpower.txt.
• At first, a Maxwellian distribution function will be considered for studying effect of the Energetic particle (EP) (produced by the different auxiliary heathing systems) on Alfvénic modes.

profili_n_bulk_n_H_new.png. The normalised buk ion density profile is given here, rhomass_181.data, as a function of the normalized poloidal flux s (s being the square root of the normalized poloidal flux function, with s=0 being the magnetic axis, s=1 being the edge of the plasma): in this file, the bulk ion density profile, assumed to be n_bulk,i=n_e as given by METIS has been interpolated and given as a function of s by using the map of rho_tor=rho_tor(s) given by the euilibrium conde CHEASE. The normalized Energetic Particle density profile (taken from the ITER SC2 scenario) is given here, n_H_dens_ITER_SC2.txt.

In the following Table 1, some physical values characterizing the equilibrium and the plasma to be used for hybrid MHD-gyrokinetic simulations will be summarized. Note that some of the normalized quantities used, e.g., by CHEASE and HYMAGYC, depend on how the EQDSK file has been written: in particular, the quantities used to scale the lengths and the magnetic field, here indicated, respectively, with R0 and B0. For the EQDSK file EQDSK_COCOS_02_POS.OUT those quantities correspond, respectively, to the geometrical major radius R_geo and vacuum magnetic field B_geo=B_vacuum(R_geo).