A Self-Consistent Analysis of Impurity Radiation by SOL-PSI Model

A model of scrape-off layer (SOL)-plasma surface interaction (PSI) coupling is presented for divertor operation. This model can treat the interrelation between impurity production and impurity radiation self-consistently. The model is based on a 'two-point' model and a 0-D steady state impurity particle balance model. The fraction of power radiated in SOL is calculated as a function of the line average density. Compared to the former simple coupling model, this model takes into account the wall-produced impurities that are sputtered by charge-exchange (CX) neutrals. A simple retention factor is also added in this model. A comparison with the experiments is made. The simulation results show the same trend upon the plasma density as shown in experiments. Reasonable qualitative agreement is reached between the results by using the model and those from experiments through the adjustment of the fitted factor.