Rakettkütused

Rakettkütused, also known as rocket propellants, are substances used to propel rockets and jet engines. They are designed to rapidly burn or decompose, producing a large volume of hot gas that is expelled through a nozzle at high speed, generating thrust. These propellants are broadly categorized into liquid, solid, and hybrid types.

Liquid propellants consist of a fuel and an oxidizer, stored in separate tanks and mixed in a combustion chamber. Common liquid fuels include kerosene, liquid hydrogen, and hydrazine, while oxidizers are often liquid oxygen or nitric acid. This type offers good control over thrust and can be throttled or shut off.

Solid propellants are a single, pre-mixed substance that contains both fuel and oxidizer. Once ignited, they burn until depleted and cannot be easily controlled or stopped. They are simpler in design and often used in booster rockets. Examples include composite propellants made from ammonium perchlorate.

Hybrid propellants combine features of both liquid and solid systems. Typically, a solid fuel is used along with a liquid or gaseous oxidizer. This offers some control over thrust while maintaining a simpler design than all-liquid systems.

The performance of a rocket propellant is measured by its specific impulse, which indicates how efficiently it produces thrust. Higher specific impulse means more thrust for a given amount of propellant, crucial for space missions. The development of new and more efficient propellants remains an active area of research.