Multi rad placement in compartimented case

[Infrabasse]

Hi,

I'm trying to squeeze in a big bunch of hard drives (12+) and a very efficient watercooling loop inside a Lian-Li PC-V2010B.

I've been playing around with Solidworks and thought of 2 general basic layouts so far
One using the flow of the fans pulling through the rads to go over the HDDs. But lower HDD mounting in that config would probably be a lot of trouble. This has a GTS240 rad in the top chamber and a GTS420 in the bottom.


The other basically has all the HDDs in the top compartment in 2 side by side 7 HDD racks, and the RAD(s) in the lower half.


In the above screenshot I've placed a GTX420 rad in the lower chamber. But I'm not sure on how to make the best use of that huge space for RADs in that lower compartment,

I've seen quite a few TJ07 cases with 2 RADs facing each other in the lower compartment, in a config probably similar to this (which is a sandwich of 2x GTX280)


Maybe I'm wrong but that seems a bit crazy unless the fans are going really high speed.
I've seen a few measurement results. On low speed, air coming out of one RAD can be up to 20-25c warmer than air going in. Having that hot air go directly into a second rad would be pretty inefficient at cooling water in that 2nd RAD and might actually make it warmer.

What do you guys think of all this?


Edit: I have the feeling the above reasoning is totally wrong. For air to get that warm on the way out of the rad, I'd have to wait for the whole loop to stabilize at it's high point temperature. But we have to take into account the cooling power of the whole sandwich here. The 2nd rad will always get warmer air going though it, not as much as 20c warmer though.
The above comments would be relevent in a dual loop though I guess.

 

[Infrabasse]

By the way carrying on the sandwich idea, which would be best?

This tight setup with not much space for the fans to breathe (only room for 3.5mm gaskets max) nor room to let them use the whole fin area, but with the most fans?


Or this apparent fan setup with room to breathe for the fans but a tough job pulling through that thick rad combo?


Or this one with room to breathe, higher static pressure, probably quieter too but no apparent fans?


A 3x140 getting fresh air with all 3 fans might still be more efficient than a sandwich of 2x140 rads, with the 2nd rad getting warmer air though. Anyone feeling like doing the math?