The type of turbine blading in which the spacing between blades remains the same size at the inlet and outlet is called?

The type of turbine blading in which the spacing between blades remains the same size at the inlet and outlet is called?

• A. Reaction Blading
• B. Impulse Blading
• C. Radial Blading
• D. Mixed Blading

Answer: (B)

In impulse blading, most of the energy transfer comes from the steam being accelerated in stationary nozzles before it reaches the rotor blades. The rotor blades then simply deflect this high-velocity jet, with little pressure change happening across the blade row itself. Because the energy extraction doesn’t rely on a changing pressure within the blade passages, the blade pitch can stay the same from inlet to outlet, so the spacing between blades remains constant along the row. In contrast, reaction blading relies on pressure changes across the blade rows to produce turning, which often requires varying flow areas and blade geometry along the row, so the spacing isn’t fixed in the same way.

In impulse blading, most of the energy transfer comes from the steam being accelerated in stationary nozzles before it reaches the rotor blades. The rotor blades then simply deflect this high-velocity jet, with little pressure change happening across the blade row itself. Because the energy extraction doesn’t rely on a changing pressure within the blade passages, the blade pitch can stay the same from inlet to outlet, so the spacing between blades remains constant along the row.

In contrast, reaction blading relies on pressure changes across the blade rows to produce turning, which often requires varying flow areas and blade geometry along the row, so the spacing isn’t fixed in the same way.