In a turboprop engine, the inlet air velocity () refers to the speed of the incoming air at the entrance of the engine’s inlet. Turboprop engines combine a gas turbine engine with a propeller to generate thrust. Air is drawn into the engine, compressed, mixed with fuel, and then burned to produce high-speed exhaust gases. The energy from these gases is used to drive a turbine, which, in turn, drives the propeller.
The inlet air velocity is a crucial parameter in the design and operation of the engine. In the context of a turboprop engine, the airflow is used not only for combustion but also to drive the propeller.
The continuity equation is based on the principle of mass conservation, and Bernoulli’s equation expresses the conservation of energy.
The continuity equation is given by:
where:
- and are the cross-sectional areas at the nozzle entrance and exit, respectively,
- and are the velocities at the nozzle entrance and exit, respectively.
which gives
where,
- A1 is the Cross-Sectional Area of Nozzle Inlet in m2
- A2 is the Cross-Sectional Area of Nozzle Exhaust in m2
- V1 is the Inlet air Velocity in m/s
- V2 is the Exhaust Air Velocity in m/s