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any recommendations for software to design a new prop? Looking for one that I can fill in the design performance fields (diameter, speeds, HP, ect) and get a good start design to produce a wood prop. Then modify depending on flight test data. Hoping for the software to supply info needed to import into autocad or solid works and have a CNC shop carve it without much converting.
Hi Skydawg - I have several books/articles on prop carving - some are virtually 'remove all material that doesn't look like a prop' - and you're done!
I attempted one, didn't finish, mainly because I realised I was making a pusher instead of a tractor!
I drew it out in solidworks, messy. It seems most of the designs are based on experience more than hard science. Clark Y seems to be a common profile, but those vary widely.
If you find one, let me know!
Mark
Take a look at JavaProp. It doesn't do everything you want, but it's free and can help get you in the ballpark.
Hi Mark, Skydawg.
Prop design is as much an art as it is a science and it includes no small measure of aesthetics. It is not by chance that there are several very reputable companies that specialize in prop design and manufacture.
Having said that, attached hereto are a couple of pages on the subject from Daniel P. Raymer's book on Aircraft Design. I think that these paragraphs give a pretty good summary of the situation in a nutshell. IMHO the only software you need is Excel to calculate the values according to Raymer's formulae, and SolidWorks to define the 3D geometry.
Note that if you're working on a fixed pitch propeller, you have to choose whether you want your prop to be optimized for cruise or takeoff - you can't have both. On the other hand, if you are talking about a variable pitch prop, you have a much better optimum range, but much more complex mechanics, and you will still have only one optimum operating point, although the off-optimum points will be closer to the optimum.
And as I noted above, aesthetics plays no small part. The blade plan-form can go from pure rectangular (like on helicopters) to "sexy" like on the Osprey, and even more sexy with small winglets like on some drone props. All have their pluses and minuses and are optimised for different operating points.
Once you know your desired optimum operating point it is quite easy to calculate (using Excel) the required blade pitch (aka "advance ratio") and required blade twist. Then you can choose your blade profile(s) - usually quite thin like Mark's Clark Y. In SolidWorks choose say 5 radial stations on which to draw your profiles with the appropriate twist angle including the angle of attack and chord length according to your chosen blade plan-form. Loft through these profiles and voila! you have your blade geometry.
Hope this helps.