Is C* Just a Name or Does It Hold Physical Significance in Rocketry?

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SUMMARY

The term C*, also known as 'Characteristic Velocity', is a critical measure in rocketry that quantifies engine performance independent of the exhaust nozzle. It is mathematically defined as c* = (A_t * p_0) / (dm/dt), where A_t represents the throat area, p_0 is the chamber pressure, and dm/dt is the mass flow rate of the propellant. The characteristic velocity is influenced by factors such as gamma, the molecular mass of combustion products, and flame temperature. This distinction clarifies that C* is not merely a name but a significant parameter in rocket propulsion analysis.

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Critical Velocity?

I've often come up with the term C* also called 'Critical Velocity' in rocketry. Is there any physical significance attached to this term or its just a name given to a combination of some constant terms?
 
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It's the characteristic velocity, not the critical velocity

The characteristic velocity is a way to measure engine performance independent of the exhaust nozzle.

It is defined as:

c*=\frac{A_t * p_0}{dm/dt}

where
At is the area of the throat,
p0 is the chamber pressure
dm/dt is the mass flow of the propellant.
 
Just wanted to add:

With a lot of re-arranging, it is a (complicated) function of gamma, the molecular mass of the combustion products, and the flame temperature.
 
yes ofcourse! I meant 'characteristic velocity' rather than 'critical velocity' and thanks for the brief but still good explanation
 

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