tim.jagenberg.info

BladeElementTheoryPropellerAnalysisTool

BETPAT is a small tool to analyse and design propellers. It implements a simple bladeelementtheory algorithm using an iterative process to approximate the inflow factors. The aerodynamic analysis of the airfoils at the stations is done by Mark Drela’s XFOIL (thanks for that!).

I wrote this tool at the Univeristy of Syndey, Australia while on a compulsory internship down under.
I’m a student of aeronautical engineering at the University of Stuttgart, Germany, and after finishing our pre-diploma we have to get some practical experience. As I’m interested in UAVs (Unmanned Aerial Vehicles) and wanted to travel Australia, I came across the UAV group at USyd, lead by Dr KC Wong. After some e-mails and a visit in his office I got the opportunity to work with him.

The main target of my project is (I’m still working on it ) to build a efficient propeller for the Bidule UAV and maybe others as well. Using the basic core algorithm wich Alexander Hill wrote in Matlab I started translating this to C++, adding a GUI with a simple geometry editor. Somewhere on the way I changed the analysis from calling XFOIL each time to table-lookup, wich made everything way faster. One of the last features I added was the DXF export, making it really easy to use the designed propeller in CAD.

With this well working tool I just designed a small (254mm) propeller, wich I will build and test the next weeks. So far the comparison of experimental results with the BETPAT prediction was quite ok. As the turbulent and other effects get stronger in these small dimensions, the prediction of small props isn’t as accurate as for big ones.

Choosing the GPL license I hope there might be some more people interested in this topic wanting to participate. Mybe someone is interested in implementing some other analysis algorithm aside BET? Anyway, I’ll go on with the development of BETPAT aside my further studies.

If you find bugs, got some ideas about what could be improved or just like the tool, just drop me note!

Cheers everybody,
Tim Jagenberg.

betpat-0600.exe win32 Installer
betpat-0600src.rar GPLed C++ source