Friday, January 6, 2012

Catch up Day

In the week after Christmas, Ralph and I worked on his Science fair project.  His Archery camp and other competitions in January meant we had to complete the build and experiment by January 2nd.  We didn't realize we had a problem with time until just before Christmas.
Anyhow, the four designs are constructed from Aluminum and riveted together.  I helped Ralph with the spindle mounts and hubs to get the blade power to a balanced shaft.  One of the things Ralph learned last year was that he needed a big enough impeller to overcome the friction of the bearings and generator and also that better precision and stronger materials were needed to ensure the windmills survived the test.  We cut Aluminum and riveted the pieces together after Bending, Ralph really seemed to like riveting and cutting the patterns out, but not good at drilling.  He also tapped threads into the hubs for the set screws.
Testing was done on Monday January 2nd and had good results consistent with expectations.  Clearly the conventional propeller had most energy from the same blade area.  The photos below are the Savonious design and the QR5.  I will try to get other pictures soon.