Interactions between liquid-wall vapor and edge plasmas

The use of liquid walls for fusion reactors could help solve problems associated with material erosion from high plasma heat-loads and neutronic activation of structures. A key issue analyzed here is the influx of impurity ions to the core plasma from the vapor of liquid side-walls. Numerical 2D transport simulations are performed for a slab geometry which approximates the edge region of a reactor-size tokamak. Both lithium vapor (from Li or Sn–Li walls) and fluorine vapor (from Flibe walls) are considered for hydrogen edge-plasmas in the high- and low-recycling regimes. It is found that the minimum influx is from lithium with a low-recycling hydrogen plasma, and the maximum influx occurs for fluorine with a high-recycling hydrogen plasma.