Integrated heat transport simulation of multi-ion-species plasma in LHD

In this study, we have investigated the heat transport of multi-ion species plasma by modifying and improving the integrated simulation code TASK3D in LHD. The impurities in the electron and hydrogen plasmas were assumed to be helium and carbon. Turbulent transport is assumed to be independent of the impurity density ratio. The ion temperature, which is higher for carbon than that for helium, increases linearly as the impurity density ratio increases. The increment of the ion temperature is due to the decrease in the effective neoclassical heat transport and the ion density. The ion temperature increment is higher in the case of lower density. (author)