Model of the near-wall conductivity in the vicinity of a macroscopically inhomogeneous, mirror-reflecting surface

A study is made of the interaction of the electron component of a low-density plasma with a macroscopically inhomogeneous, mirror-reflecting surface in mutually orthogonal electric and magnetic fields. The collisionless kinetic equation is solved analytically in the (2R+3V)-dimensional space. A nontrivial structure of the nascent near-wall currents is revealed, and their two-dimensional distribution is analyzed in detail. From the standpoint of practical applications, attention is focused on the near-wall conductivity in a stationary plasma thruster. The results obtained agree with the available experimental data. Moreover, the investigations described here provide a basis for the study of the possibility of tailoring the insulator in the channel for the purpose of suppressing anomalous erosion and ensuring the required operating period of plasma thrusters.