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I have seen propeller thrust calculations and they do not appear to have the variable of propeller width. They only use diameter or radius. What if any impact does width of the propeller have?

Here is one such post with calculation.

Is this equation for propeller thrust correct?

Aaron
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    The short answer is yes, it has to. I would presume that one of the other variables related to the coefficient of "lift' of the prop airfoil would include the width. It might help if you included the formula you are using. – Michael Hall Dec 05 '23 at 18:04
  • Agree with Michael Hall. A propeller is essentially a spinning wing, producing lift. Area is in the lift equation, although, just as in wings, a lower aspect propeller may have a higher L/D ratio, but may be able to absorb more power from the engine to create greater thrust. It would be an interesting study comparing a wider 2 blade, a 4 blade of the same (total) area, and 2 contrarotating 2 blades. – Robert DiGiovanni Dec 05 '23 at 20:06
  • By width you mean the chord or the thickness of the blade? – sophit Dec 05 '23 at 21:21
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    Not sure what you mean with "width" but for sure camber is a major factor, like the wing camber on an aircraft wing. – Andreas Lauschke Dec 05 '23 at 21:45
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    Usually when informed that an ambiguous question has been asked, people here clarify in order to avoid misunderstanding. You should too. – Pilothead Dec 06 '23 at 17:47

2 Answers2

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Yes, the average blade width -- called 'solidity' for a helicopter rotor and 'activity factor' for a propeller is an important parameter for blade thrust.

However, it gets boiled into the thrust and power coefficients typically used when evaluating propeller and aircraft performance.

Just as the chord is important for a wing, but it does not appear in the formulas for lift and drag coefficient.

Rob McDonald
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I found the following explanation of lift that does have a variable for airfoil area which would include the width of the airfoil. enter image description here https://www.experimentalaircraft.info/flight-planning/aircraft-lift-formula.php

Aaron
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