S.1 Spacecraft Propulsion Systems Chapter 1: Introduction to ...

S.8 Electric Propulsion
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In order to increase propulsion system impulse performances for e.g. interplanetary
missions, exhaust velocity has to be increased beyond the 5000 m/s, which is best
available from chemical rockets.
This can be achieved by Electric Propulsion Systems that rely on externally provided
electric power to accelerate the propellant to produce useful thrust in three ways:
- Electrothermal systems (resistojet and arc-jets)
Expansion of hot gas (which is heated by electric current) in a nozzle.
- Electromagnetic systems (magnetoplasmadynamic (MPD))
Accelerating of plasma by interaction of electric and magnetic fields to high expulsion
velocities.
- Electrostatic systems (ion engines: Kaufman, radio-frequency, field emission,
stationary plasma)
Accelerating of charged particles in electric fields to high expulsion velocities.
Survey of electrical thruster with their potential application.
Important comparison between electrical (ion) and chemical (bipropellant) propulsion. Note
the ratios of thruster specific impulse, thrust level and power requirements.