Thrust is the force that propels an object forward. In the case of rockets and jet engines, thrust starts by creating a high-pressure, high-velocity stream of gas that is expelled out of the engine. This expulsion creates a reaction force that pushes the engine and its attached vehicle in the opposite direction.
Here’s how thrust starts in different types of engines:
Rocket Engines
- Fuel and Oxidizer: A rocket engine uses fuel and an oxidizer (usually liquid oxygen) to create a combustion reaction.
- Combustion Chamber: The fuel and oxidizer are injected into the combustion chamber, where they burn rapidly, generating hot gases.
- Nozzle: The hot gases expand through a nozzle, accelerating them to high speeds.
- Thrust Generation: As the high-velocity gases are expelled out of the nozzle, they create thrust in the opposite direction, propelling the rocket forward.
Jet Engines
- Air Intake: A jet engine takes in air from the atmosphere.
- Compressor: The air is compressed by a series of rotating blades, increasing its pressure and temperature.
- Combustion Chamber: Fuel is injected into the compressed air and ignited, producing hot gases.
- Turbine: The hot gases expand through a turbine, driving the compressor and other engine components.
- Nozzle: The remaining hot gases are then expelled out of the nozzle, creating thrust.
Other Engines
Thrust can also be generated by other types of engines, such as:
- Propellers: Propellers are rotated by an engine, pushing air backwards and creating thrust.
- Rockets: Solid-fuel rockets generate thrust by burning a solid fuel.
- Ion Engines: Ion engines use electricity to accelerate ions, creating a low but continuous thrust.
In summary, thrust starts by creating a force that pushes against the engine, propelling it forward. This force is generated by expelling a high-velocity stream of gas or by pushing against a medium like air.
