Numerical analysis of the plasma behavior in a miniature microwave discharge ion thruster

The effect of magnetic field configuration on thrust performance in a miniature microwave discharge ion thruster is investigated with numerical simulation in order to improve its thrust performance. A 2D3V DMSC-PIC code has been developed to simulate the sheath potential and to estimate the electron and ion density distribution including their losses on the wall in a steady state. The number densities of ion and electron in the discharge chamber of the ion thruster are increased with increase in the number of magnet. This is because the confinement of plasma particles by the magnetic field becomes more effective and the magnetic field keeps electrons staying longer time in the magnetic tube as number of magnet increases. With increase in the number of magnet, the losses of ion and electron decrease since the confinement of particles by the magnetic field becomes more effective. The experimental result associated with the thrust performance is explained by these simulation results.