Principles of space propulsion and rockets

Question 1

What is rocket propulsion in terms of innovative space exploration?

Answer 1

it is the most widely studied non-airbreathing propulsive systems

Question 2

Airbreathing engine

Answer 2

*thrust decreases with altitude
*denisty of air is reduced
*for the same speed we have a lower mass flow rate
*limits on altitude
*an atmosphere is needed to feed the engine with air
*limits on speed
*engine must accelerate the air entering the system
*propulsive efficiency can be fairly high

Question 3

Rocket Engine

Answer 3

*thrust increases slightly with altitude
*this is due to the contribution to thrust coming from the pressure
*no limits on altitude
*oxidisers and fuel are carried by the rocket
*no limit on flight speed as the jet speed does not have to be higher than flight speed
*propulsive efficiencies of rockets are low due to the high jet velocities

Question 4

What is the typical rocket configuration?

Answer 4

*payload
*fuel storage (liquid / solid)
*fuel pumps (liquid propellant)
*combustion chamber
*propelling nozzle

Question 5

What does solid propellant allow?

Answer 5

ignitable, self-sustaining solid fuel/oxidiser mixture with central hole and nozzle

Question 6

What does liquid propellant allow?

Answer 6

USES TWO DISTINCT FLUIDS or one single propellant

Question 7

What is a benefit of liquid propellant?

Answer 7

highly efficient with excellent mixture control

Question 8

Hybrid propellant

Answer 8

the oxidiser is liquid and kept in a tank while the fuel is solid

Question 9

Solid

Answer 9

*robust
*special design of the grain to control thrust
* non -reusable

Question 10

Liquid

Answer 10

*more complex
*multiple ignitions
*hypergolic propellants
*throtteable