Intake Fan NOT flush mounted

[newpowergaming]

Good day to you all,

I have to develop a PC Case, and I am trying to get my head around the question whether it would be a good idea NOT to flush mount the intake fan in the bottom to improve airflow/decrease necessary fan RPM.

Since i have trouble describing what the problem, i made a quick Sketch-Up mock up:
Right side would be the traditional way
Left side the "free hanging" variant.

The fans on top are for exhaust.

Looking forward to your answers.

Regards Luki

 

[dorsetknob]

Welcome to TPU


I would recommend a Flush fitting Fan
Reason
if its not flush it can recirculate air from within the case via the gap
a flush mounted fan Sealed will only draw air from outside your case

 

[SithLord]

^ what he said.

On a completely unrelated, purely out of curiosity note, what are the projected dimensions/specs for the case? will there be a build log for this case project?

 

[newpowergaming]

Welcome to TPU


I would recommend a Flush fitting Fan
Reason
if its not flush it can recirculate air from within the case via the gap
a flush mounted fan Sealed will only draw air from outside your case

Thank you for your welcoming.

In my head the air inside should have "no reason" to flow downwards, since fans and heat drive it upwards. My thought is that with an open base, the air through the intake fan, could pull extra air with it. Similar to a dyson fan. ( altogh those things obviously are much more sophisticated).

Maybe i have to find someone with a CFD programm to simulate it, since i asume that the relative rpms between the fans play a role as well.

@sith Lord, the thing is supposed to be a somewhat mobile ( wheels) cube whith 40X40X40 cm, serving as a monitor stand as well.

 

[DeathtoGnomes]

Thank you for your welcoming.

In my head the air inside should have "no reason" to flow downwards, since fans and heat drive it upwards. My thought is that with an open base, the air through the intake fan, could pull extra air with it. Similar to a dyson fan. ( altogh those things obviously are much more sophisticated).

Maybe i have to find someone with a CFD programm to simulate it, since i asume that the relative rpms between the fans play a role as well.

@sith Lord, the thing is supposed to be a somewhat mobile ( wheels) cube whith 40X40X40 cm, serving as a monitor stand as well.

This intending to be mobile, you really do not want and open base for far too many reasons.

 

[jboydgolfer]

for what my 2 cents is worth, in many cases IME , when a Fan is flush mounted ,aka, mounted directly touching the intake cutout holes, you CAN, get air intake "whirring" sounds.

 

[Caring1]

Not flush mounting the intake fan could result in negative pressure and more dust will be drawn in to the case, also air will circulate around the van like a vortex mixing the cool air being drawn in and the warm air already existing in the case.
If one of the fans must be flush mounted and the other not, I would have the exhaust giving the vortex effect, the air pushed through the fan will create a suction effect drawing warm air from the case around the fan housing also and out the case.
Air flow can be checked with a burning inscence stick.

 

[newpowergaming]

Thanks for all your inputs. I have one now as well, even though its not mine. I send an Emails to a couple of Fan companies and got answeres from the Noctua support team and even the CEO of Noiseblocker believe it or not. Noctua wrote (in german): "Due to the lack of test i cant tell whether it helps airflow or not, but it sure aint no stupid idea, only problem being more dust entering and more noise exiting the case."
Noiseblocker said (also in german): " Regarding the effective cooling performence i cant see no significant difference between the two variants of mounting."

So what i take from that in the end is, dont do it. Its quieter and cleaner.

 

[trog100]

for what my 2 cents is worth, in many cases IME , when a Fan is flush mounted ,aka, mounted directly touching the intake cutout holes, you CAN, get air intake "whirring" sounds.

yep the case vent holes close to any high speed fan can generate a fair bit of extra noise.. in fact it nearly always does.. which is a shame because its how most of them are mounted..

trog