Nozzle Mass Flow Rate of a Scramjet Engine In Terms of Ideal Gas Law Calculator

A scramjet (supersonic combustion ramjet) engine is an air-breathing engine designed to operate at very high speeds, typically in the hypersonic regime. The nozzle of a scramjet engine plays a crucial role in accelerating the high-speed air and facilitating efficient combustion. Let’s delve into the definition, explanation, and calculation of the nozzle mass flow rate for a scramjet engine with SI units.

The mass flow rate ṁ through the nozzle of a scramjet engine is the amount of air passing through the nozzle per unit time. Scramjets rely on the high-speed forward motion of the vehicle to compress incoming air and mix it with fuel for combustion.

The density ($\rho$) of the incoming air can be determined using the ideal gas law:

which gives,

where,

• ṁ is the mass flow rate (kg/s),​
• $P$ is the pressure of the incoming air (Pa),
• $R$ is the specific gas constant for air (J/(kg·K)),
• $T$ is the temperature of the incoming air (K).
• $A$ is the cross-sectional area of the nozzle (m²),
• $V$ is the velocity of the air through the nozzle (m/s).