In comparison to automobile fuel, rocket fuel consists of a different chemical mixture and is utilized in a dissimilar manner than a car to propel the rocket forward. Therefore, rocket fuel cannot be expected to react in the same way that gas does in a car. Does rocket fuel, then, explode?
Rocket fuel explodes fundamentally because of Sir Isaac Newton’s three Laws of Motion. In particular, the principle that for every action, there is an equal and opposite reaction explains how intense pressure/explosion that forces gas out of a nozzle in the back of the rocket.
In order to discuss the explosion of rocket fuel, this article provides an overview of how the engine processes fuel and describes the blending of fuel and oxidizers to deliver a propellant. Also, safety and timing are crucial. If rocket fuel explodes unexpectedly, then the situation becomes extremely dangerous to anyone nearby, and in addition, the laws of motion do not take place.
Rocket Engine Use of Fuel
A rocket mechanism contains the following broad categories. The basic elements are listed as follows:
- Carrying capacity or payload
- Fuel tank
- Oxygen tank
- Rocket engine
The carrying capacity or payload refers to the amount of weight that is carried for the crew, additional oxygen, or other essential items. Also, fuel and oxygen tanks are included. The rocket engine contains the combustion chamber, where the fuel is burned, among other things, and is based on reaction energy.
Whereas, a car’s gas engine provides rotational energy to drive the wheels to turn. Similarly, an electric motor rotates a fan’s blades.
Furthermore, a car’s gas ignites in a chamber and forces a piston down, which in turn rotates a crankshaft that causes the wheels to rotate. A rocket engine forces the fuel out of a nozzle into a combustion chamber instead of forcing a piston down.
The rocket engine introduces an oxidizing agent and the fuel in the combustion chamber, causing intense pressure to an extremely hot gas, which is then forced out of the nozzle, generating thrust.
The result is an example of Newton’s Third Law of Motion that, for every action, there is an equal and opposite reaction. Gas or exhaust is forced out of the bottom, which blasts the rocket up. To illustrate, a firefighter plants his or her feet on the ground and uses great strength and body weight to counteract the huge force of the water that is projecting out of the nozzle. If the hose drops, it would reactively thrash around on the ground.
Newton’s Laws of Motion
The three laws of motion apply as written by Newton, are utilized in the launch of a rocket and the explosion of fuel. Listed below is a summary for reference purposes.
| 1 | Also known as the Law of inertia, in which objects stay in motion in a straight line or at rest unless an external force changes it. |
| 2 | The time rate of change with relation to momentum is equal in magnitude and direction to the force thrust on it. |
| 3 | Every action has an equal and opposite reaction. |
Rocket Fuel and Oxidizers Defined
Fuel is injected into the engine in order to begin the process but needs an oxidizer to propel the rocket into operation. Altogether, a rocket propellant is a combination of fuel and an oxidizer.
The types and combinations of propellants are endless. The creation and usage of a large variety of proportions need to satisfy the weight of the rocket and the travel distance required. A lot of testing is required to propel a rocket. To create a better propellant, new types using different components are being studied and tested continually.
In summary, the propellant feeds the fire that is created in the combustion chamber.
Liquid Propellant
The liquid fuel for a rocket is sometimes kerosene or liquid hydrogen (LH2), and the oxidizer is many times liquid oxygen (LOX). The propellants are injected and combined in the combustion chamber and burn at extreme temperature and pressure. The exhaust gas breaks out of the chamber through the nozzle at the lower end.
Some factors that affect the intensity are how well the fuel and oxygen are combined as well as the nozzle size. External boosters can be used to promote further and enhance the heat and energy of the propellant. Boosters fall off after use, are collected, and reused.
Solid Propellant
Rocket fuel was originally solid in composition. For example, some of the first fireworks created were made with aluminum powder as fuel and mineral salt and an ammonium perchlorate mixture used for an oxidizer. Since aluminum is a metal that is both plentiful and reactive, it was a natural choice.
In current times, the advantages and disadvantages of solid propellants are weighed against liquid propellants, which may include some of the following items:
- Efficiency
- Compact storage
- Stability
- Availability
- Safety
- Cost
- Toxicity
- Parts or mechanical failures
- Transportation
As the pros and cons of each scenario are contemplated, an applicable decision is made, and sometimes a hybrid is developed.
Hybrid Propellant
A hybrid model is also a consideration in which the fuel is in both a liquid and solid-state. Previously, this type of propellant was not popular, but it’s gaining attention due to strong safety considerations.
Professor Chris Bishop from The Royal Institution uses the principle of combustion to demonstrate how a chemical reaction is used to take fuel, combined with oxygen, to produce a rocket-like force.
While the video is fifty-eight minutes long, it is filled with a progression of demonstrations that culminated in the flight of a hybrid rocket motor. Details about the composition of the chemical mixtures, fuel, and oxidizers, that explode the rocket into flight are shared:
Danger of Explosion
Out of the many books and documentaries about satellite and rocket launches that went wrong, the book, Space Systems Failures: Disasters and Rescues of Satellites, Rocket and Space Probes, includes specific history and situations in which failures occurred, the categories the failures fall into, and the lessons learned due to the experience. In particular, structural, mechanical, and thermal failures are of interest.
The fuel system’s complexity and the dispensing of extreme heat to provide energy for various operations leaves room for great concern. Although testing is exhaustive, areas in relation to fuel and explosions include the structure and management of that extreme heat.
For instance, when in flight, the possibility of space debris or micrometeorite impact is unsettling. The operation of re-entry into the atmosphere and back to the earth also causes intense heat, approximately 3000℉ (approximately 1649℃), and the chance for something to go wrong.
Copenhagen Suborbitals explains how rocket engines work, showing the result of an engine that didn’t work very well. In this eight-minute video, the difference in pressure pushed all of the fluid into the engine and collapsed the engine causing fire:
Final Words
The inner workings of a rocket engine and its fuel systems are complex, and the component elements and arrangements are innumerable. Every element of the rocket is mechanically and chemically constructed and tested to obtain the greatest thrust.
The act of fuel combining with the oxidizer is the propellant, which creates an explosion that takes place in the combustion chamber. A chain reaction is set off that results in Newton’s laws of motion to take place, which propels the rocket forward. The variations of the fuel and oxidizers that create an explosion are endless.
Jake is a freelance writer from Pennsylvania who enjoys writing about science and sports. When he’s not writing for Temperature Master, he can be found watching the NFL or playing basketball with his friends.