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Old 06-08-2012, 02:20 PM
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Crumpp Crumpp is offline
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I agree with you this is a hard work, 1C developping team needs a lot of money and time to do so.
Yes and I don't think the differences will be worth the effort or necessarily more accurate. The current assumptions already give good agreement with in flight behaviors.

Propellers design is based on measured data. That is why you cannot work propeller theory accurately without it. That is also the reason why n=.8-.85 is a valid assumption. The design is reworked until it does achieve that level.

That was the biggest lesson of the NACA 16 series and subsequent airfoils derived from calculations. What you think on paper often does not give good agreement at that level due to compressibility.

Propellers spend most of their time in the transonic realm. Even today, the largest potential for error and the most difficult aerodynamic problems are rooted in our ability to mathematically model compressibility effects. Airfoils are designed around coefficients of pressure and our limitations for compressibility modeling hamper our ability to predict behaviors.

With the advent of CFD we are getting better but there are no CFD analysis of WWII era propeller designs.
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