Blade width (chord) variation over propellor diameter

[xoimai]

I was wondering how I should determine the chord for my propellor design at each station. Some propellors have a fixed chord while other have a decreasing chord length over the propellor diameter while others have an increasing chord length.

The only two reasons I could think of were:
- Decrease chord length from the center to the edge of the propellor to have a more even load distribution relative to the cross-sectional area (even stress distribution).
- Have max chord length at the most optimal station (optimal relative air velocity)

Thanks,

An Aerospace Engineering student

[Dave]

Unfortunately, I don't have the knowledge to even begin to answer that question. There are huge volumes of text devoted to propeller design, and it's all beyond my scope of knowledge.

[Bob Gardner]

Hi Xoimai,

We are admirers of the prop as an art form on this website. We like the wood of early props, the sensual shapes and the connection with early aircraft and warfare. But the Aerodrome website seems to abound with post grad M. Sc's, Ph. D's and D. Sc's. They are the people to ask.

http://www.theaerodrome.com/forum/

With regards,

Bob