so the thought is to have the hottest air be vented out the back and as the coolant moves closer to the front of the case it will get cooler and cooler air i know this is not common practice, but why not? there are 4 120mm rads in the spot of a single rad what are your thoughts
The classic counter-flow heat exchanger. You'd find that the gain of adding more and more radiators diminishes - you're limited by the fact that once the outlet air temperature reaches the inlet water temperature nothing useful happens. As a result, it is the mass flow of the air that likely becomes the most important factor.
As above - you get diminishing returns as the rad count increases. It makes for neater packaging of a HE unit but with the obvious disadvantage of starving all but the first rad of cool air.
Diminishing returns would kick in as above so you would have to find a sweet spot before you are spending lots to achieve little. You could maybe try to sandwich a thinner, low fpi, radiator between two thicker rads as then the back radiator would still get half decent airflow with the boost from the middle fan. Just an idea either way!
There is also the assumption that, there is a hot side and a cold side. In reality, the cooling elements, the heat sources and the water will all reach a sort of temperature equilibrium for a given load. This is why the order of components and radiators in a loop has little bearing on how effective the loop is. I would assume this is because it takes the water a number of runs through the loop before all of the excess heat can be removed.
Assuming you have the space, you would be far better off having the rads separate. Why blow hot air from one rad onto the next, when you could blow ambient air on all of them?
