Modeling of velocity distributions of dust in tokamak edge plasmas and dust–wall collisions

Velocity distribution functions of dust particles of various sizes are simulated in different regions of a tokamak using the DUSTT code. It is shown that dust particles accelerated by plasma flows can reach very high speed >1 km/s at the terminal stages of vaporization. Collisions of beryllium and tungsten dust particles with beryllium wall are modeled with the LS-DYNA material structural analysis code. It is demonstrated that the collisions at high speed ∼1 km/s can cause significant damage to the wall or complete dust destruction depending on dust and wall material parameters.