High efficiency electrothermal accelerator

Electrothermal accelerators were studied for the purpose of their application for pellet-injection in Tokamaks. Two theoretical models were developed. The first is based on magnetic hydrodynamics equations, the second is based on isobar approximation. Numerical calculations have shown there was a maximum in the curve of the total efficiency versus discharge region length, the value of the maximum being equal to 20% and higher. Experimental investigations carried out with the capacitive store element which stores 100 kJ of energy confirmed the theoretical figure for 2-15 g mass projectiles. The value of efficiency defined as the ratio of projectile kinetic energy to energy deposited into discharge was about 30%. The drastic drop of the discharge peak current was observed, so there is a possibility to increase the accelerator life time.< >