Propulsion

How do conventional rockets work?

How does density affect tank volume?

Density is the amount of space that a certain mass of material takes up. A dense material such as water is heavier than a less dense material such as gasoline for a certain size. A rocket which needs a certain mass of a fuel can use a smaller tank of a denser fuel rather than a bigger tank of a less dense fuel. The smaller tank will cost less to construct and be lighter than the large tank. However, there is a tradeoff by using a denser fuel like RP-1 or UDMH because they are lower performance fuels then LiH which produces a higher specific impulse.

Propellant Molar Mass Specific Gravity
LiF 38.0 1.43
Hydrazine 32.05 0.984
LiH 2.016 0.071
MMH 46.08 0.862
Nitrogen Tetraoxide 92.016 1.37
LiO 32 1.14
RP-1 ~175 0.58
UDMH 60.1 0.85
Water 18.02 1.00


What is a propellant?
How does propulsion work?

What are the types of rocket propulsion?
What is thrust?

How do we measure what fuels weigh?
What is specific impulse?
How do you calculate specific impulse?
What are some rocket propellants?