The working principle of this turbine

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The discussion centers on understanding the working principle of turbine blades, which are closely packed and resemble airfoils, leading to confusion about their aerodynamic function. It is suggested that these blades operate more like a series of curved nozzles that either accelerate or decelerate the fluid, rather than relying solely on aerodynamic lift. The conversation highlights the use of hybrid blade designs, combining impulse blades at the root for strength and reaction blades at the tips for efficiency. The law of momentum is referenced to explain the forces acting on the fluid within the turbine. Overall, the inquiry seeks clarity on how these blade designs contribute to turbine rotation.
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Found a video on net and from the video, the working principle that will rotate the turbine can't be understood properly. Want to know how the blades are working.
Found this video on net, but was unable to understand the working principle of the blades. The blades are very much closely packed and that means aerodynamic lift is simply useless here. But, from the video, it seems that the blades are like airfoils. That's why want to know the working principle behind the blades that will rotate the turbine.
 
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Ok. But, what's the driving principle of this rotor. Is it an impulse type turbine or reaction?
 
T C said:
The blades are very much closely packed and that means aerodynamic lift is simply useless here. But, from the video, it seems that the blades are like airfoils. That's why want to know the working principle behind the blades that will rotate the turbine.
It might be more helpful to view it as a succession of curved convergent or divergent nozzles that accelerate or decelerate the fluid (depending if you want a turbine or a compressor) rather than a succession of airfoils. Look for velocity triangle.

Example of a "curved divergent nozzle" where velocity goes from ##W_1## to ##W_2##:

60aab091be25fd85eeac62550%2Fgeschwindigkeit-4-data.jpg

The concept of a "curved nozzle" might be clearer on a centrifugal compressor (or turbine when rotating in reversed):

com%2Fwp-content%2Fuploads%2F2010%2F10%2Fimage0013.gif
 
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T C said:
TL;DR Summary: Found a video on net and from the video, the working principle that will rotate the turbine can't be understood properly. Want to know how the blades are working.

Found this video on net, but was unable to understand the working principle of the blades. The blades are very much closely packed and that means aerodynamic lift is simply useless here. But, from the video, it seems that the blades are like airfoils. That's why want to know the working principle behind the blades that will rotate the turbine.
From what I'm seeing, they're using hybrid blades. Hybrids use impulse blade design closer to the root and reaction blade design closer to the tip.

Impulse blades are like a classic Pelton turbine design, where you're simply redirecting the flow and getting your force from the flow turning. Reaction blades use the turning force and the velocity changes to produce their force. By mixing the two, you get a mix of their best attributes where they're needed most. The strength and starting torque of the impulse blades at the root and the efficiency and light weight of the reaction blades near the tips.
 
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