A Study on Effective Parameters of Radial Electric Field in IR-T1 Tokamak

  The radial electric field is calculated from the radial component of the force balance equation. It has been shown that three major driving forces have contributed radial electric field including radial pressure gradient, poloidal and toroidal rotation. In this study, we have considered the contribution of these terms, thereby calculating the profiles of plasma parameters by using fluids equations especially in the edge of plasma. Then we have obtained profiles of terms and compared them. The results have shown that the gradient of pressure, which is a negative term, makes a small contribution to the radial electric field; on the other hand, the rotational term more specifically, poloidal one makes a great contribution to it. Therefore, it seems true to say that, the sign of the field is dependent on the poloidal term.