In the context of a liquid propellant rocket engine, determining the total energy at the nozzle throat involves considerations of the enthalpy and kinetic energy of the propellants before combustion. The total energy at the nozzle throat can be expressed as the sum of the enthalpy and the kinetic energy of the combustion products.
The static enthalpy at the nozzle inlet is the specific enthalpy of the propellant mixture before combustion. It is a measure of the internal energy associated with the temperature and pressure of the propellants. The kinetic energy term accounts for the motion of the combustion products.
The total energy () at the nozzle Inlet can be expressed as:
where,
- E is the Total Energy, i.e sum of kinetic and potential energy
- Â is the Static Enthalpy at nozzle Inlet,
- is the velocity of the combustion products at the nozzle inlet (m/s).