Heat loads in the inner and outer plate regions are computed with XGC0. The results for the inner plates are shown below:
The results for the outer plate are stored incorrectly. This problem with the code needs to be investigated. Also, the ion thermal flux is too noisy despite that more than 3,000,000 particles have been used in this simulation. The heat fluxes are also found to be unexpectingly low.
A set of XGC0 simulations has been run to determine the anomalous transport coefficients that can be used together with the neoclassical transport, which self-consistently computed with XGC0, to reproduce the experimental profiles for four DIII-D current scan discharges. Below the final diffusivity parameters, initial and final profiles are given.
132014.03000
tbl_d_profile_on=-1 ! 1: spatially varying D_turb profile (tanh), 0: spatially constant profile in pedestal region tbl_slope_on=0 ! D_turb turned on only within finite poloidal angles (+45 deg) around outside midplane tbl_d_profile_psicen=0.93D0 ! D_turb profile center tbl_d_profile_psiwid=0.02D0 ! D_turb profile full width tbl_d_profile_psicen2=0.995D0 ! D_turb profile center tbl_d_profile_psiwid2=-0.01D0 ! D_turb profile full width ! particle diffusivities (random walk diffusion coefficients) tbl_D_coeff_in=0.2D0 ! m^2/sec, inside (pedestal top) value of D_turb tbl_D_coeff=0.01D0 ! m^2/sec, outside (pedestal bottom) value of D_turb tbl_D_coeff2=0.1D0 ! m^2/sec, D_turb for outside of separatrix (SOL+private flux region) ! ion thermal diffusivities tbl_therDi_coeff_in=.070D0 ! m^2/sec, inside (pedestal top) value of thermal D_turb for ions tbl_therDi_coeff=-0.050D0 ! m^2/sec, outside (pedestal bottom) value of thermal D_turb for ions tbl_therDi_coeff2=0.6D0 ! m^2/sec, thermal D_turb for outside of separatrix (SOL+private flux region) for ions ! electron thermal diffusivities tbl_therDe_coeff_in=0.8D0 ! m^2/sec, inside (pedestal top) value of thermal D_turb for electrons tbl_therDe_coeff=0.03D0 ! m^2/sec, outside (pedestal bottom) value of thermal D_turb for electrons tbl_therDe_coeff2=0.6D0 ! m^2/sec, thermal D_turb for outside of separatrix (SOL+private flux region) for electrons
132016.03023
tbl_d_profile_on=-1 ! 1: spatially varying D_turb profile (tanh), 0: spatially constant profile in pedestal region tbl_slope_on=0 ! D_turb turned on only within finite poloidal angles (+45 deg) around outside midplane tbl_d_profile_psicen=0.94D0 ! D_turb profile center tbl_d_profile_psiwid=0.02D0 ! D_turb profile full width tbl_d_profile_psicen2=0.995D0 ! D_turb profile center tbl_d_profile_psiwid2=-0.01D0 ! D_turb profile full width ! particle diffusivities (random walk diffusion coefficients) tbl_D_coeff_in=0.13D0 ! m^2/sec, inside (pedestal top) value of D_turb tbl_D_coeff=0.04D0 ! m^2/sec, outside (pedestal bottom) value of D_turb tbl_D_coeff2=0.3D0 ! m^2/sec, D_turb for outside of separatrix (SOL+private flux region) ! ion thermal diffusivities tbl_therDi_coeff_in=0.1D0 ! m^2/sec, inside (pedestal top) value of thermal D_turb for ions tbl_therDi_coeff=-0.05D0 ! m^2/sec, outside (pedestal bottom) value of thermal D_turb for ions tbl_therDi_coeff2=0.7D0 ! m^2/sec, thermal D_turb for outside of separatrix (SOL+private flux region) for ions ! electron thermal diffusivities tbl_therDe_coeff_in=0.25D0 ! m^2/sec, inside (pedestal top) value of thermal D_turb for electrons tbl_therDe_coeff=0.02D0 ! m^2/sec, outside (pedestal bottom) value of thermal D_turb for electrons tbl_therDe_coeff2=0.7D0 ! m^2/sec, thermal D_turb for outside of separatrix (SOL+private flux region) for electrons
132017.02998
tbl_d_profile_on=-1 ! 1: spatially varying D_turb profile (tanh), 0: spatially constant profile in pedestal region tbl_slope_on=0 ! D_turb turned on only within finite poloidal angles (+45 deg) around outside midplane tbl_d_profile_psicen=0.91D0 ! D_turb profile center tbl_d_profile_psiwid=0.02D0 ! D_turb profile full width tbl_d_profile_psicen2=0.995D0 ! D_turb profile center tbl_d_profile_psiwid2=-0.01D0 ! D_turb profile full width ! particle diffusivities (random walk diffusion coefficients) tbl_D_coeff_in=0.13D0 ! m^2/sec, inside (pedestal top) value of D_turb tbl_D_coeff=0.015D0 ! m^2/sec, outside (pedestal bottom) value of D_turb tbl_D_coeff2=0.2D0 ! m^2/sec, D_turb for outside of separatrix (SOL+private flux region) ! ion thermal diffusivities tbl_therDi_coeff_in=.1D0 ! m^2/sec, inside (pedestal top) value of thermal D_turb for ions tbl_therDi_coeff=-0.20D0 ! m^2/sec, outside (pedestal bottom) value of thermal D_turb for ions tbl_therDi_coeff2=0.9D0 ! m^2/sec, thermal D_turb for outside of separatrix (SOL+private flux region) for ions ! electron thermal diffusivities tbl_therDe_coeff_in=0.35D0 ! m^2/sec, inside (pedestal top) value of thermal D_turb for electrons tbl_therDe_coeff=-0.01D0 ! m^2/sec, outside (pedestal bottom) value of thermal D_turb for electrons tbl_therDe_coeff2=1.5D0 ! m^2/sec, thermal D_turb for outside of separatrix (SOL+private flux region) for electrons
132018.01948
tbl_d_profile_on=-1 ! 1: spatially varying D_turb profile (tanh), 0: spatially constant profile in pedestal region tbl_slope_on=0 ! D_turb turned on only within finite poloidal angles (+45 deg) around outside midplane tbl_d_profile_psicen=0.89D0 ! D_turb profile center tbl_d_profile_psiwid=0.02D0 ! D_turb profile full width tbl_d_profile_psicen2=0.995D0 ! D_turb profile center tbl_d_profile_psiwid2=-0.01D0 ! D_turb profile full width ! particle diffusivities (random walk diffusion coefficients) tbl_D_coeff_in=0.05D0 ! m^2/sec, inside (pedestal top) value of D_turb tbl_D_coeff=0.002D0 ! m^2/sec, outside (pedestal bottom) value of D_turb tbl_D_coeff2=0.2D0 ! m^2/sec, D_turb for outside of separatrix (SOL+private flux region) ! ion thermal diffusivities tbl_therDi_coeff_in=0.3D0 ! m^2/sec, inside (pedestal top) value of thermal D_turb for ions tbl_therDi_coeff=-0.1D0 ! m^2/sec, outside (pedestal bottom) value of thermal D_turb for ions tbl_therDi_coeff2=0.7D0 ! m^2/sec, thermal D_turb for outside of separatrix (SOL+private flux region) for ions ! electron thermal diffusivities tbl_therDe_coeff_in=.2D0 ! m^2/sec, inside (pedestal top) value of thermal D_turb for electrons tbl_therDe_coeff=0.07D0 ! m^2/sec, outside (pedestal bottom) value of thermal D_turb for electrons tbl_therDe_coeff2=0.7D0 ! m^2/sec, thermal D_turb for outside of separatrix (SOL+private flux region) for electrons
Preliminary results for the particle and heat fluxes in the divertor area for a sequence of times (t=60, 65, 70,75, and 79 ion transit times) are shown below. These results are obtained in relatively long simulation XGC-O15 with increased number of particles.
The anomalous diffusivity profiles that can be used in XGC-0 in order to reproduce the experimental profiles in the Alcator C-Mod discharge 1100212024 are finally found. The particle and thermal diffusivity profiles are shown below. Also, the radial electric field, plasma density and total ion temperature are shown as well. It has been found that the ion temperature profile can be reproduced only if the thermal and particle pinches in the pedestal area is introduced. The results are still to be analyzed. There is a small hump in the density profile that is associated with gradient change in the diffusivity profile at around tbl_d_profile_psicen2.
During the last week, CPES team members (CS, G-Y Park, SH Ku and myself) visited the MIT PSFC. Jerry Hughes and Jim Terry provided eqdsk data and experimental plasma profiles (plasma density and temperatures) for the Alcator C-Mod discharge 1100212024 that represents an identity experiment between Alcator C-Mod and DIII-D. A number of XGC-0 simulations has been run during the visit. The objective of these simulations was to find the diffusivity profiles that can be used in the XGC-0 code in order to reproduce the experimental density and temperature profiles. The eqdsk data has been altered to fit the XGC-0 mesh requirements. The modified eqdsk data are shown on the plot below.
The final diffusivity profiles is identified to have the following shape
It is found that the transition to the SOL anomalous transport occurs in the SOL region rather than in the pedestal region as for DIII-D. The transport levels are still need to be adjusted in order to accurately reproduce the density and [especially] temperature profiles.
It is planned that these simulations will be expended in order to (1) study the heat load on the divertor plates; (2) identify the instabilities that contribute the most to the anomalous transport in this region; (3) study the formation and evolution of radial electric field in the pedestal and SOL regions.
Linear NIMROD run for 22 toroidal modes is submitted on hopper. The constant plasma density is being used 
Simulations for the TTF meeting are summarized on the attached Flash slides.
The theory motivated flow shear suppression yields reasonable anomalous transport suppression level as one can see from the comparison below. Left panels show results with theory motivated factor with fm_cexb coefficient equal to 1, while the right panels show results with imposed flow shear factor.
DIII-D discharge 132014
DIII-D discharge 132016
DIII-D discharge 132017
DIII-D discharge 132018
The coefficient might need to be increased somewhat (especially in the SOL region).
Multiple issues with the new version of FMCFM are finally resolved. The code is ready for production runs.
Problems related to recent merge to the svn repository are fixed. The problems were caused by incorrectly initialized fmcfm variables in the setup subroutine. The changes are committed to the repository.
