Right now, I'm leaning towards a triangle-based hole punch tool and making a pattern from that base shape.
Recently on one of his live streams, Josh @NFC said his patented SKYSLOTS on the S4MINI were specifically designed because of their aerodynamic properties. I believe he actually consulted with an aerodynamics engineer and noted that, for some reason, that slot style has some inherently advantageous characteristic that promotes both air inflow and outflow compared to other vent styles.
This may have something to do with their curved aspect of the openings and their size (volume) compared to more angular openings. Openings with more angles may be deleterious, since air flowing into or around any angle (especially those acute angles that form a triangle) can bunch up more and create more turbulence compared to a shape with no angles, such as a circle or elongated circle. Again, we want as much
LAMINAR airflow as possible and want to avoid
TURBULENT airflow. Circles and their variations will do that more than triangles.
In the past year, I've personally written a number of peer-reviewed manuscripts on obstructive sleep apnea (OSA) and airway characteristics. Volume AND shape of the airway are very important to promote a laminar flow. In other words, even if you increase airway volume, air flow path can still be turbulent, thus shape of the airway is still a critical factor, just like the shape of a wing or elevator or engine cowl. Of course, with OSA we're talking airway dynamics in terms of cylinders, but my point is I believe the same principles can apply to vents to some degree.
Take this FANTASTIC study on different fan vents,
Effects of Grill Patterns on Fan Performance/Noise:
https://www.pugetsystems.com/labs/articles/Effects-of-Grill-Patterns-on-Fan-Performance-Noise-107/.
It was published back in 2011 by Puget Systems, a custom PC shop outside Seattle. These are the patterns they tested:
Their conclusion was based on both
noise and
airflow (remember, both greater noise and impaired airflow are factors that are directly caused by more TURBULENT airflow).
They ranked the patterns from best to worse:
- Wire
- Swirl
- Loose Swirl
- Stamped Circles
- Honeycomb
- Mesh
- Concentric Circles
- Angled Slats
- Turbine
Honeycomb is right in the middle and performs decently. We can't fault the honeycomb in the S401 at all because I think it does the job nicely. I applaud that
@grsychckn chose honeycomb over the stamped circles (pinhole mesh, basically), the latter of which causes a high-pitch whine. But there's another factor here favorable to the honeycombs: the struts separating them essentially act create a small hex cylinder (3mm or so), or in other words act as fins directing airflow out. If you had a pattern with larger dead areas in-between, you'd impede airflow. Even if triangles are chosen, keep them as close together as possible to maximize airflow by decreasing the area of obstruction as much as possible.
My vote would be a variation of the Loose Swirl (#3). I would think we want to avoid the more fragile arms of the typical #2 Swirl pattern. Just like #2, #3 Loose Swirl is essentially a skewed triangle but with more curvature in the acute angles. Its angles are not necessarily super-hard angles like the #2 Swirl pattern, and they have more volume. I'm solidly in favor of larger vent openings (greater volume). I would modify #3 even more to make both ends more curved, say like a twisting tear drop.
Right now, my plan is to remove the front vent holes and move the power button back to the middle (probably going to drop SFX-L support as the SF750 is just as good as any SFX-L).
Please keep SFX-L support! It's all I'll ever use because of the larger, quieter fan. We can argue all day about pros and cons, but SFX-L is popular, and I'd hate to see others choose a different case based on incompatibility with SFX-L.
I'm constantly trying to reduce the number of parts required while also not making things more complicated. The solid side panel is only necessary to cover the mounting hardware and the mainboard rear access hole. I think if I can use the flex slot for the GPU area, I'll be able to remove nearly all the embossed screw holes which then only leaves the mainboard hole to figure out.
@grsychckn
What do you mean "use the flex slot for the GPU area"? Do you mean have an opening on the backside of the chassis in the GPU area? That would be VERY flexible so I won't have to cut out the chassis to make way for fans on that side. If you recall, my build has the GPU on the bottom of the chassis laying against the solid wall. If that side was also vented with whatever pattern you end up choosing, or if you make that back lower half a removable "flex" panel, I could put the radiator/fans on the bottom and bring the GPU to the top side where its plexi-water-RGB glory can be seen.