Simulation on Heating and Current Drive Using Neutral Beam Injection with Variable Injection Angle on EAST

The heating and current drive using NBI (neutral beam injection) with a variable injection angle (the angle between the axis of the NBI system with the center axis of the injection window) on EAST is simulated by using NBEAMS code. The influence of the injection angle on the neutral beam current drive, heating efficiency and beam shinethrough power is discussed to explore the optimum injection angle for the EAST NBI system. According to the simulation, an injection angle of 19.50 is the optimum for EAST with its typical experimental parameters. With this injection angle, the increase in both the beam energy and power can improve the current drive and heating efficiency. The problem that the beam shinethrough power increases with the higher injection energy and power could be controlled through an increase of the plasma density.