Airflow direction -- Improving the cooling of my computer

[Riogunati]

TL;DR Summary

Need to know what happens after airflow from 3 different sources and 3 different directions meet

Hi,
First of all I am sorry if I post in an incorrect thread. I can ask my question in PC forums but I thought it probably better if I ask in physics forum.

So, I am trying to make the temperature in my PC better by adding additional fans, however I can't really place the fans in whatever direction I want. So after looking at the PC chassis for awhile, I found some interesting spots where I can add a new fan. I said interesting because if I put the fans at those spots, 3 airflow will meet at the middle, and I need to know what might/will happen for that situation. I attached a simple image of the directions, sorry if it's bad drawing, I suck at ms-paint.

All fans mentioned in this post are of the same size.
Directly ontop of the purple fan, will be another fan in the same direction as the purple one in the picture.
On the top and below of the airflow meeting point there will be a metal plate with some bit of small holes.

I hope you guys at this forum willing to help me with this.
Thank you in advance.

 

[anorlunda]

It would be more effective if some of the fans were exhaust fans, blowing air out instead of in.

It is common to pair fans, one blowing into a confined space, and the other blowing out. It increases air flow in the middle.

 

[Riogunati]

Thank you for the welcome, and for the reply

If you meant have some exhaust too not just all intake in a fairly closed environment, then yes, there is 2 fans that exhausts at the opposite side. Adding more probably will put the inside of my PC case in a negative pressure condition, which I don't want (Dusty outside environment).

But since the thermal condition of (and because of) some parts needs some help, I thought to add more fans, which is those 2 red ones in the picture.

I just want to know wether the collided airflow will :
A. Join together and move toward the direction of the purple fan flow.
B. Move toward a direction without addition.
C. Clash and negate each other's flow, then the air spreads to random direction(s)

My goal is to add more fresh cool air into the chassis and direct them toward a certain direction (in the picture, UP) if that at all possible. Without adding some sort of a plate to direct the side fan's airflow. Because adding those plates might choke/bottleneck the purple fan's airflow.

I would do a live try if only good and consistent PC fans not expensive.

 

[davenn]

This …...

It would be more effective if some of the fans were exhaust fans, blowing air out instead of in.

If you meant have some exhaust too not just all intake in a fairly closed environment, then yes, there is 2 fans that exhausts at the opposite side. Adding more probably will put the inside of my PC case in a negative pressure condition, which I don't want (Dusty outside environment).

well you have 4 in and nothing out. This does not help with cooling as the air inside the case is only going to get hotter. make 2 of those 4 fans exhaust fans to get rid of the hot air.

I just want to know wether the collided airflow will :
A. Join together and move toward the direction of the purple fan flow.
B. Move toward a direction without addition.
C. Clash and negate each other's flow, then the air spreads to random direction(s)

probably mostly C

Again, you need to get rid of the hot air. It isn't going to do any good just circulating in the case getting hotter and hotter

Dave

 

[Riogunati]

Here is the actual diagram, sorry, should have just drawn it in the first place. The pic I posted in my first post is if you see the airflow direction from the top.

None of the exhaust fans' airflow can't really be reversed for another intake, because there is very hot components near it or under it (like around 70-90 degrees celcius), some almost directly under / ontop each other, so like if I put the top as another intake, that will mean pushing down hot air to parts under.

 

[256bits]

Summary: Need to know what happens after airflow from 3 different sources and 3 different directions meet

On the top and below of the airflow meeting point there will be a metal plate with some bit of small holes

What is the reason for the perforated plate? If anything.
You do realize that it is another impediment to the air flow.

One thing -not knowing which parts of your box is generating heat that needs to be removed, it is difficult to even give a reasonable answer. Adding another fan may increase the airflow in/ out of the box, but the hot component may just be set into stagnant air and overheat anyways.