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Airfoils are used in the blades of a propeller as well as the blades of the fan, axial compressor and turbine in a turbofan engine. Thus, the airfoils used in above two applications have different purposes. In propeller, the lift from the airfoil is used for generating thrust. Whereas, in a turbofan engine, airfoils are used for adding and extracting work from the flow in the compressor and turbine sections respectively. Therefore, my question is what are the characteristics of the airfoils employed in both propeller and turbofan engine, and how they vary from each other. Also, how different is the blade section of a fan with respect to the ones in axial compressor and turbine.

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  • $\begingroup$ Note that in turbojet engine, most of the thrust is still generated by the compressor—in fact, there is more force acting on it than the total thrust, because there is negative thrust on the turbine cancelling part of it—and that a propeller also adds work (energy) to the air stream. So the principle is exactly the same in both cases. The difference is mainly in the speeds involved, the fact a compressor works against a pressure gradient, and the solidity ratio. $\endgroup$ – Jan Hudec Mar 24 '18 at 20:12
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The angle of attack range of a propeller airfoil is larger than that of a turbofan. Therefore, the turbofan can get away with a thinner airfoil and much more camber. Also, the aspect ratio (ratio between length and chord) of a propeller blade is much higher, so the airfoil needs to be thicker to allow the blade root to carry the radial loads and to produce less torsion so the propeller blade does not twist too much under load. Were the turbofan blade as thick, the higher solidity of a typical turbofan would mean that the fan blades would block most of the flow path.

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