Cryogenic rocket engines use cryogenic propellants, which are gases or liquids that exist at extremely low temperatures. The most common cryogenic propellants are liquid oxygen (LOX) and liquid hydrogen (LH2). Cryogenic rocket engines are commonly used in space exploration due to the high energy content and efficiency of cryogenic propellants. The low temperatures help increase the density of the propellants, resulting in a higher mass flow rate and improved performance.
The thrust equation for a turbojet engine using control volume analysis is expressed as:
where,
- is the thrust force,
- ṁe is the mass flow rate of exhaust gases in kilograms per second (kg/s).
- is the Exhaust velocity at the nozzle exit in meters per second (m/s).
- ṁ0 is the mass flow rate of inlet gases in kilograms per second (kg/s).
- is the Exhaust velocity at the nozzle Inlet in meters per second (m/s).
- is the Pressure at the nozzle exit in pascals (Pa).
- is the Pressure at the nozzle inlet in pascals (Pa).
- is the Area of the nozzle exit in square meters (m²).