Aspects of comet-like acceleration of ablating dust in tokamak SOL

Vertical Disruption Events (VDE) in tokamaks, may cause significant melting along tile ridges of the vessel upper dump plates with release of metallic particulate and droplets as shown in and in references therein. Accurate studies of the motion of such debris released in the vessel are important for the inventory of tritiated composites in a reactor. Recently numerical codes have been developed to track this particulate of variable mass and charge, in interaction with the Scrape-Off layer (SOL) plasma. Here a contribution is given for a more consistent discussion of the additional acceleration of the dust due to asymmetric loss of mass in flight. A simplified description is constructed in analogy with the physics of comets.