In making solar collector absorber plates that use grooved aluminum fins pressed over copper tube risers, it is very important to clamp the fins to the tubes very tightly in order to maximize the heat transfer from the fin to the riser tube. This page shows a simple clamp that Kenneth worked out to provide the clamping force.
Kenneth's clamps
in place holding the aluminum fin tightly to the copper tubing.
Note the good tight wrap on the tube -- this is what you want to see.
The clamps are made from 4 inch schedule 40 PVC pipe.
Click on pictures for full size
Making the clamps.
Comments:
I just went out to the shop an made one of these clamps. They are quick to make, and they have a good deal of bite -- a nice idea!
This issue of making fins and providing a good thermal bond between the fin and the copper tube has been worked on by several people -- quite a few alternatives have emerged -- all summarized here... -- lots of choices.
Gary
Gary March 22, 2010