Computation of neutral gas flow generation from a CT neutralization fuel-injector

The feasibility of compact torus (CT) neutralization fuel injection method is studied by a simulation model using particle and MHD hybrid techniques. The neutralization process is simulated by using rate-coefficients. The magnetic and electric fields are found to respond sluggishly to the neutralization process. Slow ions generated by charge-exchange have been added to the model, although the CT neutralization process was not significantly affected by this. Finally, the minimum length for the CT neutralizer is proposed as 2 m from the simulation run time 10 μs at a CT injection speed of 200 km/s. (author)