Originally Posted by joeblack5
At skoolie palooza I met someone who had a large panel ripped out of its frame because of wind load while driving. Forgot the details...but he and some others build a casing around the panels so the wind could not get under it.
What are your thoughts?
I would be interested in the details about the skoolie you mention above. I have seen panels "secured" with bungy cords...
Originally Posted by PNW_Steve
...Kind of an air dam to direct wind around the panels and not under them.
The front of my rack will have an air dam built into the decking.
Originally Posted by o1marc
I would think air under them could be a cooling benefit and keep debris from accumulating under them.
Air flow under panels (when parked especially) good... Panels generating lift when moving bad...
As you can see from my snarky comment yesterday, the subject of strength and TFOB (things falling off buses) is not a can of worms I am excited to open...
However, while I did not do any full scale fatigue testing or computer analysis, I did seek to build in some design features I believe will help reduce risk. I am sure some of the stronger opinion holders here may not share my opinions and perspectives on reducing the risk of TFOB... but here they are:
1) The height of the rack - The rack was purposely mounted as low to the roof as I could while still leaving room for air flow. The center rail is flush mounted and less than an inch high.
2) The rack to roof mounting design - The racks are bolted into the tubular cross members of the bus roof (every ~28 inches for the outer rails and every~18 inches on the center rail). No stress bearing components of the rack are attached solely to sheet metal.
3) The panel to rack mounting design (triple rack design)- The solar panel rack was built from three continuous runs of Super Strut. Three sections provides for 6 mounting points (vice 4)
4) The use of decking - Once the install is fully complete there will be an uninterrupted surface of decking and solar panels stretching the entire length of the bus. In fact the first full ~6 feet or so of the roof will be decking. The front of that decking will have an air dam to encourage air to move over the panels.
5) Aluminum angle iron trim - This trim will be used to improve the appearance of the decking edges as well as to tie panels together. I will also be bolting the panels together near the edges to further tie the panels together.
In conclusion, I definitely considered the location and environment these panels will be living in, and I did seek to take active measures to keep them on the roof. Although I did not use grade 8 fasteners, and likely left other risk reducers on the table, I am pretty confident that the steps I did take will be more than sufficient to keep the panels safe and sound.
I am considering additional "wind deflectors" mounted to the bottom of some panels, but they are still conceptual at this stage...