Abstract
Electric propulsion engines differ from thermal engines in that, among other things, the propellant does not serve as an energy source to heat and accelerate the propellant mass in the combustion chamber. Rather acceleration is achieved by accelerating ions in an electric field, the energy of which needs to be provided externally by an electric current source. This is both an advantage and a disadvantage at the same time. The advantage is that, theoretically, any amount of energy can be applied to the propellant mass which would in principle permit unlimited exhaust speeds, hence unlimited specific impulse, and therefore unlimited efficiency of the engine. The disadvantage is that the structural mass of the rocket stage increases due to the additional mass of the electric generator, which directly trades with payload mass. Massive generators are required especially for high-\( I_{sp} \) engines, so their additional mass may outweigh propellant savings. Therefore, comparisons between different propulsion systems always need to consider the total propulsion system mass: propulsion system, consumed propellant, plus energy supply system.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Change history
31 October 2019
In the original version of the book, the following belated corrections are to be incorporated.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
Copyright information
© 2018 Springer Nature Switzerland AG
About this chapter
Cite this chapter
Walter, U. (2018). Electric Propulsion. In: Astronautics. Springer, Cham. https://doi.org/10.1007/978-3-319-74373-8_5
Download citation
DOI: https://doi.org/10.1007/978-3-319-74373-8_5
Published:
Publisher Name: Springer, Cham
Print ISBN: 978-3-319-74372-1
Online ISBN: 978-3-319-74373-8
eBook Packages: EngineeringEngineering (R0)