Many of you have probably seen the Falcon 9 launch in May.
After watching, have you ever wondered how those giant rods of metal go into space?
Well, all that thrust is created by the rocket’s engines and boosters which convert chemical energy into kinetic energy.
All rockets use Newton's third law of motion which states that for every action, there is an equal and opposite reaction.
To produce thrust, rockets combust a mixture of a fuel and an oxidizer.
Because combustion is rapid oxidation, where the object being burned loses electrons to the oxidizer, oxygen is necessary when burning anything.
An oxidizer is any chemical substance that *surprise surprise* oxidizes another substance.
So, why is having an oxidizer important?
Because when combined with any fuel, which is a substance that can be reacted to release energy, the oxidizer can provide oxygen and help the fuel burn.
In space, there is no oxygen, so combustion would not be possible without these oxidizers.
To the left is sugar, but if I burn it, it doesn't really do much.
So, next is potassium nitrate, which is an oxidizer, but by itself, it doesn't do much either.
However, if you combine them, it becomes a pyrotechnic mixture.
There are two main types of rocket engines, solid-fuel, and liquid-fuel.
Solid-fuel engines consist of an oxidizer and fuel that are pre-mixed in solid form, while liquid-fuel engines consist of a cryogenic liquid oxidizer and fuel.
However, it is much harder to store and use liquid-fuel engines as they have to constantly be kept at low temperatures.
So why do we even bother using liquid fuels?
We use liquid fuel engines as they are much more efficient, which is why most payload or manned missions like the Saturn V used liquid-fuel engines.
There are also 2 types of liquid fuel rocket engines; hypergolic and non-hypergolic.
Hypergolic means that when they are mixed, they spontaneously ignite.
So, by changing how much fuel and oxidizer are mixed, scientists can control how much thrust the rocket is producing.
However, because of their extreme toxicity and corrosiveness, hypergolic propellants are difficult to handle.
I’m going to use the old baking soda and vinegar reaction as an example.
These two chemicals react spontaneously, so they're considered hypergolic.
And because we can control how much vinegar we add to the baking soda, we can control how much it bubbles.
So just imagine that the bubbling is combustion and you got the basics of a hypergolic rocket engine.
For liquid-fuel engines, most rockets use a cone-like nozzle called the converging-diverging nozzle at the end of the rocket engine.
The nozzle mainly serves to increase the exhaust velocity, which in turn increases the thrust of the engine.
Around the nozzle, there are tubes in which the fuel flows through so that it can cool down the nozzle and save some energy.
On the top of the nozzle, there is a combustion chamber where the oxidizer and fuel are mixed in an efficient way and burned.
A fuel pump and an oxidizer pump are used to make sure the oxidizer and fuel have an adequate flow rate.
These pumps are connected to a turbine, which provides power to the pumps.
A hot gas generator will produce gas to turn the turbine.
The future of rocket science has so many possibilities, as we have only left Earth 60 years ago.
I encourage all of you to explore the study of rockets and space, as this is only the beginning of our exploration of the universe.
