Rocket fuel explanation
Whether it is personal vehicle or space launch system (SLS),combustion reaction is the one mechanism that makes things go.Basically,rocket launching uses newton’s third law of motion which is every action has an equal and opposite reaction.A rocket engine use the force of explosion to accelerate off the earth and also accelerating through space.The force of hot gas expanding in a combustion chamber that being directed throughout the rocket nozzle is what pushes the rocket off the planet and this is how a rocket also fly through space.
Basically,water and aluminium makes a rocket system fly.A simple chemistry is used to make rocket fuel.For a space launch system to fly,combustion reaction takes place in two primary areas:The main engine and the solid rocket booster.The main engine is basically called “liquid engine”.This is because the fuel is liquid H₂ (LH₂) and liquid O₂ (LOX),which is used as oxidizer.H₂ is the lightest element that exists as a gas.A gas takes up a lot of spaces thats why H₂ and O₂ is turned into liquid which is denser than gas,at -423°F and -297°F respectively.As LH₂ and LOX is cryogenic those evaporate fast.That is why SLS is loaded with propellants just a few hours before launching.When launch countdown is nearing zero LH₂ and LOX are pumped into the combustion chamber.When the propellant is ignited,the hydrogen reacts explosively with oxygen to form water.The reaction release a massive amounts of energy along with superheated water which is stream.
2H₂ + O₂ = 2H₂O + Energy
The H₂-O₂ reaction generates tremendous heat that makes the water vapor expand and exit thoughout the engine nozzle at speeds of 10000 miles per hour.This whole rocket launching is measured by specific impulse (Specific impulse is a measurement of engine efficiency taking into account for rocket and spacecraft changing mass as it burns it’s fuel).LH₂ and LOX propellant mixture has the highest specific impulse of any commonly used rocket fuel.But still because of its low density,carrying enough LH₂ as fuel for the reaction,needed to leave earth’s surface would required a tank too big,too heavy and with too much insulation protection for the cryogenic propellant.That’s why,another mixture of liquid oxygen and RP1 which is highly refined version of kerosene is also used as a fuel.But here is some other problems too.This propellant mixture remove sulfer which has a tendency to make fuel turned to gunk that blocks up fuel pipe which is a big problem when you are trying to pump tons of fuel through the engine.Still LOX and RP1 mixture is more considerable because kerosene is liquid at room temperature and it is much denser.This mixture is used in most of the rocket with advance engineering technology.
To give SLS extra power to gets off the ground,rocket booster is used that burn tons of solid propellent each second and help SLS to break free from the clutches of earth′s gravity.Solid rocket fuel is the original rocket fuel dating back to the early firework.For the SLS booster,aluminium is used as fuel with ammonium perchlorate as the oxidizer mixed with a binder that creates a homogenous solid propellent mixture.Aluminium is the most abundant and highly reactive.This is so reactive that it is not found naturally in it′s pure form.We use Al in many stuffs.But amazingly this is also used as fuel for rocket booster.In the booster the aluminium powder and ammonium perchlorate are hold together by a binder,poly butadiene acrylonitrile or PBAN.When it is burns,O₂ from the ammonium perchlorate combines with aluminium and produce aluminium oxide,aluminium chloride with vapor and nitrogen gas and a lot of energy.This reaction heats the inside of the solid rocket booster to more than 5000°F causing the water vapor and nitrogen to rapidly expand.Just like the liquid engine,the expanding gases comes outward though the nozzle,creating thrust and lifting the rocket from the launch pad.Compared to liquid engine,solid propellant mixers have lower specific impulse.But still this is useful because the propellant is dense and burns quite quickly generating a whole thrust in a very short time.After leaving the launching pad,the boosters are discarded,lighting the load for the rest of the spacecraft.
When a rocket is in space,it is not effective to use chemical reaction as it needs a tons of fuel.A chemical reaction is strong enough to get rid of launch pad but in space it is not the best way to fly.That’s why there are some more types of fuel.
Electric/ion propulsion:Inside the ion engine,electron are stripped from atom and charged ions are spread out at the electric field before being shot at the end of the engine providing thrust.
Nuclear propulsion:A nuclear thermal rocket generates thrust by using cryogenic hydrogen to cool efficient reactor core.The gas is heated and expands.The expanding gas is directed through the nozzle to generate thrust.
This kind of fuel has higher specific impulse.Moreover,Rocket needs less fuel in this types of energy creation.Ion engine needs electricity to provide the reactor and that comes from massive solar panel.Nuclear engine have nuclear reactor that’s why it is dangerous because if anyhow the rocket explode,this will creat chaos.But still with advance engineering technology,most of the rocket use this.
Though there are many more kinds of rocket fuel.But this is amazing how applying force of mass in one direction so that the equal and opposite force is applied in the other direction,accelerate a spacecraft.
