[SOLVED] will it have good airflow a neutral one?

[phoonon]

i have an thermaltake v200, with 3 fans 1 rear and im asking if will i have an positive or negative airflow , laso is considered with a gtx 1660 3 fans ,corsair cxm 650 w artic freezer 34 duo ,and that but i also like to put 2 more fans: be quiet!pure wings 2 140mm x 21.500 RPM máx., 51 CMF, 19dB(A).

Is it necessary to put this fan on the case or the airflow will be good without necessarily puting 2 more fans (intake and exhaust)?

 

[DavidM012]

When intake fans' combined airflow is greater than exhaust, a positive pressure is created inside the chassis. Conversely, when the airflow is greater for exhaust than it is for intake, a negative pressure is created.

The be quiet pure wings aren't all that quiet. I have 2 120mm's 19dba and I don't like them on full speed. They are quiet but not quiet enough for my liking.

Some Enermax 120mm's are as good as 140mm

This one

Pressure fan will prolly do something for your airflow. The noise will only be as quiet as the quietest fan so you may not get any benefit from the low noise enermax and the airflow will be as high as the highest airflow fan. It has a airflow of 83cfm at full speed. And the price is about the same, and the dba at full speed, 20dba so you can get more airflow with about the same noise as the be quiet.

At least you can think of it as more airflow with no additional noise.

 

[phoonon]

When intake fans' combined airflow is greater than exhaust, a positive pressure is created inside the chassis. Conversely, when the airflow is greater for exhaust than it is for intake, a negative pressure is created.

The be quiet pure wings aren't all that quiet. I have 2 120mm's 19dba and I don't like them on full speed. They are quiet but not quiet enough for my liking.

Some Enermax 120mm's are as good as 140mm

This one

Pressure fan will prolly do something for your airflow. The noise will only be as quiet as the quietest fan so you may not get any benefit from the low noise enermax and the airflow will be as high as the highest airflow fan. It has a airflow of 83cfm at full speed. And the price is about the same, and the dba at full speed, 20dba so you can get more airflow with about the same noise as the be quiet.

At least you can think of it as more airflow with no additional noise.

but with replacing the components you mentioned will i have neutral airflow?

 

[DavidM012]

I don't know what fans you have already. Neutral would be, I suppose, when your intake and exhaust fans are all the same model and specification since you have different fans already, it wouldn't be neutral.

It's only going to be as quiet as the loudest fan and as high as the highest airflow fan. If you put the enermax as an exhaust it would be negative pressure if you put it as intake, as the highest cfm fan, the pressure would be positive.

 

[phoonon]

I don't know what fans you have already. Neutral would be, I suppose, when your intake and exhaust fans are all the same model and specification since you have different fans already, it wouldn't be neutral.

does it count gpu and cpu coolers and the psu fan? the cpu cooler i have its ARTIC esports one 34 duo

 

[DavidM012]

No the highest cfm fan will do all the pressurising work.

 

[phoonon]

No the highest cfm fan will do all the pressurisingand.

finally , what happens if i put 1 of the fans you mentioned on exhaust and the other intake?

 

[DavidM012]

Should be neutral

 

[phoonon]

Should be neutral

but keeping in mind the v200 case has 3 120mm fans intake and 1 exhaust?

 

[DavidM012]

The highest cfm fans will do the pressurising work.

 

[phoonon]

The highest cfm fans will do the pressurising work.

so , yes . Thank you ! <3

 

[Karadjgne]

It changes.

Fans almost never run 100%, most times getting a case fan naturally past @ 70% is a chore and you can not go by cfm as a basis as that changes too, all you see is max rpm values, which are pretty meaningless. Fan cfm does not respond linearly. In other words you might get 100% cfm at 100% speed, but you will not get 50% cfm at 50% speeds. Depending on fan blade design, rpm etc you could get anywhere from 20% cfm to 90% cfm at 50% speeds.

So it's entirely possible to have a negative at idle, neutral at gaming and only get a positive at max, or the other way around.

And that's only in a sealed system. There's generally enough unused fan vents, gaps in slots by the gpu, mesh next to the exhaust fan etc that negative/positive is an attitude more than a reality.

When a fan blade moves through air, it creates a low pressure area behind it. Get enough blades moving through that area, at high enough rpm, you create a low pressure area that extends into the case. Nature abhors a vacuum, so the air inside the case will move to fill that low pressure area in a constant flow. But, that low pressure area will be filled by the nearest available air, if it's an empty top mount fan hole, that's where the air will come from, easy access. A negative system is where there's not enough supplied air to adequately fill that low pressure area and the vacuum is using outside air next to it. A positive system has enough supplied air that it floods the low pressure area, not allowing for much (if any) outside air draw.

At idle speeds, you'll more than likely have a negative system as there's simply not enough input air to flood even a relatively weak exhaust, it'll pull the air right next to it first. At max rpms that'll change. Generally.

One of the best airflow cases available is the fractal design meshify c. 3x 120mm intake, 1x 120mm exhaust and relatively well sealed, no other fan vents. This allows the vast majority of exhaust draw to come from only 1 place, the case, which is well supplied. If the case had 2x 120mm top vents as well, airflow would go in the toilet as that'd be where the exhaust fan would be pulling all its air from first.

 

[DavidM012]

bit of card and tape could do wonders for it.

 

[Karadjgne]

True. For the most part, unless you have a tower style cooler that directly faces the rear exhaust, then with open fan vents in the top of the case, a rear exhaust is next to useless. Far better off putting it up top.