keel and rudder design

[max]

Hi there,

I´m searching for a software to calculate keels and rudders.
I saw a programm called wings in the net but wasn´t able to run the trial version with windows 2000 nor with windos 98.
Has anybody got experiences with this programm or knows similar software or has a trial version wich is ok ?

Thanx,

Max

[SailDesign]

Past experience dictates that analysing foils in 2D is all very well, but the real world has other ideas. You can find just the right section from the puter for max lift, low drag, etc, but if the 3D flow is erratic it can, and probably will, be a complete waste of time.
Don't ask me why I know this - please!
Steve

[Goodwin]

Originally Posted by max

Hi there,

I´m searching for a software to calculate keels and rudders.
I saw a programm called wings in the net but wasn´t able to run the trial version with windows 2000 nor with windos 98.
Has anybody got experiences with this programm or knows similar software or has a trial version wich is ok ?

Thanx,

Max

I've got the same with wings/windows xp
and am also searching for such software.
If you can find anything can you pass it throug??

TNX, S.

[nico]

I think a good aerodynamic book would be best. Learn the theory and write spreadsheets or program when needed.

you can this;

http://www.hanleyinnovations.com/

[redcoopers]

If you want your own section, I'd recommend xfoil (which includes viscous or inviscid calculations): http://raphael.mit.edu/xfoil/

It's only 2D, but just like posted before, it's terribly difficult to worry about 3D effects. However, most people assume that a wing will only have 3D effects at the root and the tip. If your keel is bounded by your hull at the root, and you have a really big bulb at the tip, I'd just make the assumption that your keel is an airfoil, and not a wing. If you don't have a bulb, or it is not big enough, you just need to remember that the effectiveness of your keel will be reduced because of an induced vortex.

I'd also get a book published by Dover: Theory of Wing Sections. This book is important because you can find what's called a "drag bucket" for low Re numbers for a given section. Designing a keel correctly to fit the drag bucket will be a really big improvement.

-Jon

[Chris Krumm]

Try the site for XFLR5 for a graphical user interface to XFOIL for 2D foil design. It's much easier to use than XFOIL itself, and uses XFOIL's code. Inverse design routines have recently been implemented. The download is free and source code is available if you're interested. Be sure to download the foil library as well.

http://mapage.noos.fr/xflr5/xflr5.htm

Chris Krumm