Specific Impulse for a cold gas propulsion rocket nozzle is a parameter that measures the efficiency with which a rocket engine using cold gas as a propellant converts that propellant into thrust. Cold gas propulsion systems typically use compressed gas, often stored at ambient temperature, for thrust generation. Specific Impulse provides a metric for comparing the performance of such propulsion systems.
In a cold gas propulsion system, the gas is expelled at high speed to generate thrust. The specific impulse is influenced by factors such as the pressure of the stored gas, the mass flow rate, and the nozzle design. Cold gas thrusters are commonly used for attitude control and small maneuvers in spacecraft.
It is defined as the thrust generated per unit of propellant expended and is expressed in seconds.
where,
- is the specific impulse of the rocket engine (in seconds, s)
- F is the Thrust Produced
- ṁ is the mass flow rate of propellant in KG/Sec
- g0 is the acceleration due to gravity