Negative Air Pressure

Dundain

Senior member
Dec 24, 2000
585
0
0
Ok, here's a question I was pondering last night at 1am (Dont sleep well) but anyways. Say I have 3 fans in my case, which is a standard Mid-Tower. Fan in front is an 80mm, then a blow hole at the top which is 120mm, and at the rear of the case you have the 80mm PS fan, and another 120mm fan blowing out.

Now since this is a negative air pressure, it should suck air in through any hole opening possible, correct? Well, say you seal all those holes (and I know you cant do this 100% but bare with me) so the only places it can draw air is through the front fan. Wouldnt this technically force the fan to spin faster, which would in turn increase the amount of air being pulled in?

Could you then in turn combine this with a fan stacking technique to increase the air inflow even more, but with less visible difference to the case, etc?
 

mechBgon

Super Moderator<br>Elite Member
Oct 31, 1999
30,699
1
0
Having some basic fluid dynamics knowledge from my ChemE studies, I forsee the front fan being able to spin faster since the air it's moving is already being pushed into the case by the pressure differential between the inside and outside. Stacking fans just doesn't do much in my experience. I tried stacking fans on a socket 7 cooler on my old K6 266 and the CPU temperature went up, not down.

With two 120mm exhaust fans and an 80mm exhaust fan, you would have a severely unbalanced system and it would be strangled by the limited intake area of most bezels. At the very least, leave the ventilation holes/slots on the side panel unblocked so they can help make up some of the difference. You might also try cutting off the bottom of the bezel if it's restrictive, which would leave it looking stock but allow a lot more airflow. Here is a pic of my modified bezel: Click on the follow-through link if necessary, Tripod is like that.