Design
| Enviro |
Astro | Propulsion
| Power | Thermal
| Structures | AD&C
| CDHS |
Test
Propellants
are heated by absorption then expand through a nozzle
to high exhaust velocities.
Thermal
Rockets
Electrothermal
propulsion uses electricity to heat propellant.
A conventional nozzle then converts this thermal
energy to kinetic energy. The resistojet and arcjet
are electrothermal systems. The resistojet uses
electrical resistance to produce heat; the arcjet
uses an electrical arc discharge to produce heat.
These systems have demonstrated Isp
between 1000 to 1500 seconds.
Solar-thermal
rockets concentrate
solar energy at a single point to heat hydrogen
propellant. Isp
reaches over 800 seconds.
Nuclear
heat transfer
rockets use a fission reaction to heat hydrogen
propellant. Isp reaches up to 1000 seconds. The
Nuclear Engine for Rocket Vehicle Applications (NERVA)
program developed and tested nuclear-thermal rockets
from 1947 to 1972. It was canceled for political
and environmental concerns.
