GAS-TARGET EXPERIMENTS IN HIGH HEAT-FLUX PLASMA OF THE TPD-I DEVICE

Gas target experiments are performed in the TPD-I device, which produces a high density helium plasma similar to 6x10(19) m(-3) with an electron temperature around 10 eV. The maximum plasma heat flow is estimated to be about 20 MW/m(2). A strong reduction of electron density and temperature was observed by feeding a secondary helium gas into the plasma and a stable detached plasma is formed in front of the target plate. The radial profile of the electron temperature is changed from peaked to hollow as the gas pressure is increasing. These experimental results are compared with the plasma simulations performed with the 2D plasma fluid B2 code. Good agreement with the simulated radial profiles of the plasma parameters is found.