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In the stator of a turbine, the gas velocity V and static pressure p vary as follows:
  • A
    V decreases, p increases.
  • B
    V decreases, p decreases.
  • C
    V increases, p decreases.
  • D
    V increases, p increases.

Refer to figure.

Gas Turbine Engines - TURBINE SECTION
The purpose of the turbine is to extract as much energy as possible from the air exiting the gas chamber. This is achieved with the guide vanes and blades, by harvesting energy from the expanding hot air and therefore the kinetic energy of the airflow. Meaning the turbine will use the high pressure from the hot air exiting the combustion chamber and convert that into useful energy.

  • Pressure decreases: In the figure it can easily be seen that the pressure decreases along the turbine section of the graph.
  • Axial velocity increases: Even though the main purpose of the turbine is to extract energy from the air entering the combustion chamber, the airflow is actually faster in the turbine section than it is in the combustion chamber. Along the turbine, the axial velocity fluctuates up and down as it passes through each guide vane and turbine blade.
  • As the turbine extracts energy from the air, the temperature decreases axially the further it gets from the combustion chamber.
In stator of turbine pressure drops and velocity of airflow increases while in rotor velocity and pressure both decrease.
Note: In the compressor section (rotor + stator) => V decreases and P increases.
In the turbine section (stator + rotor) => V increases and P decreases

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