Effect of viscosity on magnetohydrodynamics behavior during limiter biasing in the CT-6B tokamak

Full text: Effects of Viscosity on Magnetohydrodynamics Behavior During Limiter Biasing in the CT-6B Tokamak has been investigated. The results shown that subsequent to the application of a positive bias, a decrease followed by an increase in the frequency of magnetic field fluctuations was observed. With contribution of viscous force effects in the radial force balance equation for Limiter Biasing, in terms of the nonstationarity model, it allows us to identify the understanding physics responsible for change in the Mirnov oscillations that could be related to poloidal rotation velocity and radial electric field. It could be seen that the time scale of responses to biasing is important. the response of ∇pi , decrease of poloidal rotation velocity, the edge electrostatics and magnetic fluctuations to external field have been investigated. Therefore, the results shown that momentum balance equation with considering viscous force term can be use for modeling of limiter biasing in the tokamak. (author)