The effective exhaust velocity (Ve) for a rocket engine is a crucial parameter that characterizes the engine’s performance. It represents the speed at which the exhaust gases exit the rocket nozzle. Ve is typically expressed in units of meters per second (m/s) or feet per second (ft/s).
The effective exhaust velocity can be calculated using the following formula:
Ve = √(2 * specific heat ratio * pressure ratio * (R * Tc))
Where:
- specific heat ratio (γ) is the ratio of specific heat capacities at constant pressure (Cp) and constant volume (Cv) for the working fluid. For an ideal gas, γ = Cp / Cv.
- pressure ratio is the ratio of the exit pressure (Pe) to the chamber pressure (Pc).
- R is the specific gas constant for the working fluid.
- Tc is the chamber temperature in kelvin (K).
This formula is derived from the isentropic flow equations for compressible fluids and is used to estimate the effective exhaust velocity based on the engine’s operating parameters.
It’s important to note that the specific heat ratio, pressure ratio, specific gas constant, and chamber temperature can vary depending on the type of propellant, engine design, and operating conditions. Therefore, accurate determination of Ve requires knowledge of these parameters and may involve complex calculations or testing.