The thrust coefficient (Ct) for a scramjet engine is a dimensionless parameter used to characterize and compare the thrust performance of the engine under various operating conditions. Scramjet engines operate in the hypersonic flight regime and rely on supersonic combustion of air and fuel. The thrust coefficient is calculated using the following formula:
Ct = (T / (ρ * A * Vj))
Where:
- Ct is the thrust coefficient (dimensionless).
- T is the actual thrust produced by the scramjet engine in newtons (N).
- ρ is the air density in kilograms per cubic meter (kg/m³).
- A is the engine inlet area in square meters (m²).
- Vj is the jet exhaust velocity of the engine in meters per second (m/s).
The thrust coefficient allows for standardized comparisons of scramjet engine thrust performance across different operating conditions, design parameters, and aircraft applications. It quantifies how effectively the engine converts the kinetic energy of incoming air into thrust.