Attaching fins behind a solar panel

[sam_smk]

We want to increase the efficiency of our solar panels at home by decreasing their temperatures.

Is there an equation that would help us calculate the distance between each fin and how many fins we should install? And an equation to calculate the suitable shape of fin to be using? And should there be space between the fins edges of the solar panel?

 

[berkeman]

Here's an article that may help: http://www.sciencedirect.com/science/article/pii/S187661021502888X

Click "Download Full PDF" at the bottom of the page to read the full article.

 

[CWatters]

Interestingly they put the fins horizontally across the air flow rather than vertically parallel with the air flow. The latter is more normal.

 

[JBA]

It would have been informative if they had discussed the reason they restricted the testing to only this horizontal perforated type of rib as opposed to the conventional longitudinal orientation, ie prior studies, testing, etc.
It would appear that this design would make each successively higher fin less effective due to the preheating of its impinging air by the prior lower fin and the most effective configuration with the 45° angle into the approaching flow would tend to increase that effect. As a result, it would appear that the most flow impeding design that extents the contact air is the most efficient.
Another issue I observed about their testing configuration is that by an identical length for the fins in the test the fins actual projection length into the flow is greater for the 90° fin configuration than that of either of the angled fin configurations, i.e. for equal projection the length angled fins would need to be 1.4 times that of the perpendicular fins. As a result, the heat transfer efficiency of the angled fins would appear to be even greater than illustrated at equal flow penetration depths.

 

[CWatters]

It would appear that this design would make each successively higher fin less effective due to the preheating of its impinging air by the prior lower fin

You get something similar with most heat sink designs, even with the conventional longitudinal arrangement one end is usually hotter than the other.

As a result, it would appear that the most flow impeding design that extents the contact air is the most efficient.

I think it's quite difficult to be sure what's optimum as it's only convection that's moving the air.