The diffusion density profile model for multiple-mirror devices is limited to machines with a large number of cells and high mirror ratios. A new discrete staircase density profile model, without those limitations, has been developed. This model, along with the diffusion model, has been used to study the parameters of steady-state multiple-mirror reactors. A linear fusion device consisting of a central solenoid and multiple mirrors at each end has been considered. The magnetic field is taken to be produced by a solenoid and mirror-quadrupole assemblies which produce an average-minimum-B stable configuration. Different means of supplying the re-circulating power, including high-energy neutral-D injectors, are considered. Distribution functions of alpha particles and beam particles in this machine have been calculated. Trade-offs among the length of the machine, Q ≡ fusion power/beam power, and other machine parameters in two different operating modes: wetwood burner (pure-T plasma background) and conventional (T and D background plasma) have been studied. It is found that the staircase density profile results in shorter reactors with a larger number of cells, compared to those of the diffusion-determined density profile.
Plasma distribution function near the loss cone of a mirror machine