FAA Powerplant Written Practice Test

Which component of a turbine engine acts as a diffuser and converts velocity to pressure?

1. Rotors

2. Stators

3. Combustion Chamber

4. Exhaust Nozzle

The correct answer is: Stators

In a turbine engine, the component that acts as a diffuser and converts velocity to pressure is the stator. Stators are stationary blade assemblies that slow down the fast-moving air coming from the rotors. As air passes through the stator vanes, its velocity decreases while its pressure increases. This is a key principle in compressible fluid dynamics, as the design of stators allows for effective energy conversion and pressure recovery. The function of the stator is crucial in maintaining efficient airflow throughout the engine, which is important for overall performance and efficiency. In contrast, rotors are responsible for generating thrust by accelerating the air, while the combustion chamber is where fuel and air mixtures combust, generating high-pressure gases. The exhaust nozzle, on the other hand, is designed to convert pressure back into kinetic energy to project the exhaust gases at high speed, thereby creating thrust. The distinctive roles of these components highlight why the stator is specifically recognized for its ability to diffuse air and facilitate the conversion of velocity to pressure, pivotal in managing airflow and maintaining the performance of the turbine engine.