Modelagem Numérica de Inicialização em Plasmas de Tokamak

Abstract

In this work we use the hydrodynamic theory, where we treat the plasma stateas a fluid, in order to model plasma initiation in a Tokamakwhere a neutral gas isionized and becomes a plasma.The Tokamak is until now the the most promising and tested approach for obtaining the controlled thermonuclear fusion that has the potential of becoming a practically inexhaustible source of clean andrenewable energy. The process of plasma initiation inside a Tokamak vacuum chamber is called plasma start-up and can be divided in threephases: the avalanche or breakdown phase, the burn of impurities or burn-through and the established plasma current or ramp-up. With aresidual initial amount of electrons it was possible to evolve the shot through its three initial phases while obtaining the behavior of importantparameters such as current, density and pressure, so to have a better understandment of the underlying mechanisms of thestart-up process and help to prevent failures during this phase of the shot.