One row of fixed blading and one row of moving blading.

One row of fixed blading and one row of moving blading.

• A. A cascade
• B. A vane set
• C. A rotor group
• D. A stage

Answer: (D)

A stage in turbomachinery is the energy-transfer unit formed by one row of fixed blades and one row of moving blades. The fixed blades set the flow direction and angle, guiding the fluid onto the rotor blades, while the moving blades (the rotor) extract or impart energy as the fluid passes through. This pairing is the fundamental building block of a turbine or compressor, and stacking stages increases the overall pressure change or energy transfer. Other terms describe just one part or a testing setup (a cascade is a row of blades studied in a test or flow path; a vane set is the stationary blades alone; a rotor group is the rotating blading alone), but only a stage means both fixed and moving blades together working as a single energy-transfer unit.

A stage in turbomachinery is the energy-transfer unit formed by one row of fixed blades and one row of moving blades. The fixed blades set the flow direction and angle, guiding the fluid onto the rotor blades, while the moving blades (the rotor) extract or impart energy as the fluid passes through. This pairing is the fundamental building block of a turbine or compressor, and stacking stages increases the overall pressure change or energy transfer. Other terms describe just one part or a testing setup (a cascade is a row of blades studied in a test or flow path; a vane set is the stationary blades alone; a rotor group is the rotating blading alone), but only a stage means both fixed and moving blades together working as a single energy-transfer unit.