Wednesday 1 April 2009

Foiler Performance Calculations from Alan Smith

I did NOT create this program and I am not claiming any credit for it. I got this from Alan Smith and rather than just post it I thought it was worth introducing a bit. Therefore I am posting some info copied from his mails in my Blog because it is the quickest way to get it on-line.

Bill Beaver’s excellent scientific paper, released publically via the international moth web site has prompted me to offer a foiler performance estimating program that I have developed.

The attached program is in excel and that may limit the range of users. Hopefully anyone with access to excel will not have any problem using it. The drag parameters of the computation have the benefit of Bill B’s work. This validation is of comfort but is not actually that important. The important aspect of the program is that it correctly indicates the sign and the order of magnitude of each partial derivative for many of the variables available to the designer. It provides answers to many of the questions the moth guys keep asking and illustrates that selecting the best geometry is more important than selecting foil sections. It does on the other hand provide the designer a knowledge of foil loadings and cL’s hence enables the selection of foil sections best suited to the aspect of sailing where he wishes to perform ahead of the pack.

The reason for developing the program is my long time interest in foilers; a deep interest in the dynamics of aircraft (40 years of UAV development) and now foilers; I have a number of 3DofF foiler simulation model running; have been watching the moth evolution and amazed at many of the misunderstandings that are out here even among the to guys. As I said in my first email, this program provides a lot of answers!

The program has a brief set of "sailing" instruction on the opening page. It also contains a 60 day self destruct algorithm. I will remove this for any serious users on a one on one basis.

Alam Smith
April 2009
alans at aapt dot net dot au

The program can be downloaded here.

In due course I will do a Science | Technical | Boffins |.. Ideas on a postcard please | page on the IMCA site and collect together various papers and programs for the geeks out there.


Felix Schulte said...

Hi Doug, I just wanted to remind you that it is your birthday today. So get a few friends together, tell them to bring beer and enjoy yourself

Anonymous said...

The link to download the program seems to be broken. Can I get some help?