by angib » Tue Jan 03, 2012 11:38 am
I'm not sure if the Land Rover 'safari roof' was pressed aluminium (all the LR body is aluminium, due to wartime steel shortages when it was first made!) or some other hard material, but it is certainly rigid, not fabric.
It works because the forward movement of the vehicle blows air between the cabin roof and the safari roof, so the cabin roof is only at ambient air temperature. Without the vehicle's movement, it wouldn't work.
For an exposed trailer, one logical adaptation would be make some sort of chimney effect where as air under the safari-like roof got warmed, it would rise up by convection and so draw in ambient air. That requires a serious slope, say 45 degrees or more, which is probably too much slope for the solar panels.