I'm trying to choose some new front fans for a Fractal Define Mini (acting as NAS and HTPC, among other things).
I'm filling up all 6 slots with hard drives and so keeping air going over them with the two front fans is a concern (as is noise). The things that I think are particular to this situation are the fan filters and the proximity of the fans to the drive cages.
The cages are oriented sideways and only have some thin holes for air to pass above the hard drives. They are located directly next to the front fans, with just a few cm between the fans and the cage. Also, the filters on the front are a pretty fine metal mesh, so that is in the mix as well.
What would be the best type of 120mm fans to push air through this area? I think case fans are usually recommended assuming a more open environment, which I am not sure this is. Is it restricted enough that I need to take it into account? I have been looking at various fan reviews, but I am not sure which parameters are most important in this situation.
Pictures of the filters and front area (air is pulled in from the sides of the front panel): http://www.silentpcreview.com/article1230-page2.html
Pictures of the drive cage and it's location (with cage vent size and spacing easy to see): http://www.silentpcreview.com/article1230-page3.html
Other parameters: I won't be adjusting the fan speed; this will be sitting in a corner so I just want to set it and forget it. There is no "high load" situation I would want to turn them up for, but the drives will see a decent amount of use, there are a lot of them, and these fans are also the intakes for the whole case. I have the fan controller that came with the case, but I'd rather not use it because its position is awkward.
In case it matters, the box has a Noctua NH-C14 heatsink (with only the top fan on), a passive Seasonic PSU, and a passive AMD HD 6450 vid card. The hard drives are all WD Red 3TB. I was planning on using one of the Fractal stock fans for the rear fan slot, but I guess I am open for suggestions for a replacement there too if it makes sense.
Thanks for any suggestion you might have!