Pellet and molecular beam injection fueling on the HL-1M tokamak

The Eight-shot Pellet Injector (EPI) and Molecular Beam Injector (MBI) as new plasma fueling methods have been developed and installed on the HL-1M tokamak for fueling experiments. The main structures and characteristics of the fueling device and the typical fueling experimental results with EPI and the MBI are reported. In these experiments, typical responses of plasma in discharges with PI and MBI are the peaked density profile Q(n) = n(e)(0)/<n(e)> of >1.65for MBI and of 2 for PI. The improvement of confinement time tau(E) is usually better than 10 to 30% of Gas Puffing (GP) discharge in the same operation condition. In addition, the penetration depth and deposition region of fueling particles, the variance of soft X-ray sawteeth, the rotation and flow of plasma in edge region as well as the photographing of ablation clouds with PI and MBI are compared and presented in this paper.