EFFECT OF A MAGNETIC FIELD ON THE SPACE CHARGE NEUTRALIZATION PROBLEM IN ELECTRIC PROPULSION.
Technical rept. Feb-Nov 66,
AEROSPACE CORP EL SEGUNDO CA
Pagination or Media Count:
Some basic aspects of ion beam neutralization in the presence of magnetic fields are investigated. The problem leads to an integro-differential equation for the electrostatic potential. This equation is solved numerically for several values of the electron-ion mass ratio. Of more interest for practical applications is the limit as the mass ratio tends to zero. In this case, the governing equation becomes linear and the problem reduces to finding the inverse of a Hilbert transform. The solution can be expressed in terms of elementary functions. Among the results obtained are the distribution of the charge densities for electrons and ions in the beam, and the electron trajectories. The limiting condition for beam reversal, which applies when the magnetic field is sufficiently strong to prevent the electrons from being drawn into the beam, is determined. Also computed is the loss in propulsive efficiency due to electron-swirl. Finally, it is pointed out that this loss can be entirely avoided if a magnetic field is employed whose transverse component changes direction. Author
- Electric and Ion Propulsion