Gadgetory

what is going on everybody J's two cents here and I said in the EVGA closed-loop cooler video but I wasn't entirely convinced that their new fan design was really all that beneficial so rather than just say I'm not sure that actually works I decided to do some science and test that theory for myself now let's go ahead and preface this with the obvious this is not the most scientific way to do this I'm reusing dry ice to give me some vapor to actually have a visual representation of what the airflow is doing I can't see airflow with my eyes the downside of using dry ice is the vapor is heavier than air so that's going to have a little bit of an effect on how the air flow actually happens but fortunately the amount of pressure that these fans and most fans can generate is going to overcome the weight or the slightly heavier weight of the dry ice paper and that shouldn't be too much of an issue now they do have very scientific machinery that you can use to measure air flow and air shape and airfoil direction and all that crap unfortunately I don't have access to that because very very expensive so we're doing this just a real ghetto method here in my office but I think the results should give us at least some idea of what's really happening here so with all that out of the way let's go in just do a little bit of a dramatic b-roll of some of the testing here and it will dive into the testing and go ahead and talk about the results so a couple things we'll start with here I do have 35 minutes of test footage on this yeah don't worry we're not going to go through all 35 minutes I will not torture you with that but I did also do testing here by taping off the sides of the fan to create a more traditional style slightly flawed although it did give me some interesting perspectives though as I did not tape off the middle of the fan we'll talk about that a little bit as to why this was a bit of a flawed test as well as why this also gave some pretty interesting insight also - before people start yelling that the GPU is going to have some sort of effect on this test I did actually test that and as you can see right here the GPU is running at very low rpm and these fans over here are still drawing the air to it so the GPU is having very little effect on any of this testing now the first test here I'm just using the dry ice paper here kind of back and forth on the fans to see the way it kind of behaves in front of the fan and off to the side of the fan now you can see right here it's obviously being drawn in you can see a pretty direct u-turn happening right here as it's pouring out of the beaker or the container whatever you want to call it and it's coming right into the center of the fan and my concern with this fan design though was the swoop design right here on the corners of the fan and what prompted this whole test was I could feel air splashing back towards the face of the fan where it wasn't making its way through the fan into the radiator the resistance was actually forcing air to escape out the sides creating a bit of a vortex right here as a circular design or a circular shape so I'm using the vapor to kind of give me a visual representation of what I was feeling and check this out as the vapor comes over to the side of the fan you can see right now it's still being drawn in I'm right over the top of the corner right here but as I get to the side watch what happens as I come over to the side check it out look at how much right now was just blasted back away from the fan do you see this you see how there's a clearly velocity being pushed this way because I'm off to the side of the fan now so I'm trying to see what the actual behavior of the for his when it's being drawn in from the side of the fan but you can see right now quite a bit of air is physically pushing the vapor away as you can see right here again it's going to reverse that you see how much instead of being drawn in right here in this section around the corner into the fan which is what would typically happen you are getting quite a bit of velocity now pushing this vapor away from it which is now giving us what would be perceived as very turbulent air in front of the fan now it's obvious air is being pushed through the rad you can see it right there I'm not disputing that air is going through the radiator I just was questioning whether or not this design is actually beneficial now as we still air in from the middle of the fans where both of these fans are creating quite a bit of draw you can see it's being pulled into the center of fan just fine it's being pulled into the radiator it's being pushed through but again as we come out to the side watch what happens in this area right here boom did you see that you see how now there's a there's a divide there's a split happening right here I could feel that with my hands and that's what was concerning me now what happens when we tape off the sides of the fans here to see if we can actually get rid of this turbulence because you can see right here you can see it with your eyeballs as a split it's coming this way and it's going that way check this out we look in Reverse and there we go you can see just as much air is being pushed away as what's being drawn in which makes it seem like a very inefficient design now this is 240fps slowed down to 60fps so this is effectively four times slower than real-time and you can see quite a bit of areas obviously being drawn in but you'll see as we get to the side though quite a bit of air is going to be pushed away you see in super slow-mo here as we get to the side you can see again right here watch as it spills out you see how this is already being pushed away latest coming this way and that's not this air is not being drawn towards the cooler at all let's look at look up here in this area right here watch how much of this air is actually pushed away right there as we are off towards the corners of the cooler but again you come back towards the middle it's still being drawn in but it's being pushed away first so it's a bit of a spiral effect happening here in front of the cooler now when I test this with the tape on the fans kind of making it a little bit more of a traditional shape you can see we get a little bit different behavior here as I pour it in it's all being drawn into the face of the fan there's always going to be some backdraft though I mean that's what happens when you have resistance which in this case is represented by the radiator but you can see that there's a lot less resistance happening here it's being drawn in around the corner it's being drawn into the fan at this point it's kind of hard to see in the video I'm quite a bit of weight from the radiator right here and quite a bit of ways away from it so I'm trying to see how much of its actually being drawn in but you can see there's a lot less turbulence happening off to the side at that 45 degree angle it's not pushing the vapor all the way out here another angle in real time you can see when we get off to the side here though how it's being literally drawn into the radiator it's being pulled around the tape and in it's creating quite a bit of a vacuum which is kind of what is what you want with a fan you're creating a vacuum to pull air through or push air or whichever direction you're actually orienting your fan now another angle of the same effect here you look at how much is actually being pulled out of the container and directly into the fan now right here I'm directly over the corner of the radiator I check this out now I am closer to the camera than I am to the actual radiator but it's being cooled out of the container right here and into the fan we're not having any turbulence right here check this out look at this this is very streamlined and very efficient airflow now I did test whether or not having some sort of resistance above it would make a difference representing say the roof of a case or something allowing this area to not have any influence on what's happening now it's already happening down here with the foam that the radiator is resting on but it didn't really seem to have any adverse effects by having it be an open environment right in front of it after all we are checking the characteristics of the airflow it doesn't really seem to have any effect so I did test that though quite a bit actually at least 10 minutes of it but I won't force you to watch all that now the reason why you're seeing in this test right here some of the air being pushed back even though we have the tape going around the edges of the fan as I didn't separate the center of the fans so we have the air being siphoned in around the side of the perimeter of the fans as we want but however the middle of the fans right here though is still being pushed out so we do have what is kind of an artificial barrier between the fans because air is coming the opposite direction and you can see that represented right here with the the container now just one last time here comparing the super-slow-mo 240fps you actually get a very good visual representation of what some of my concerns were here with this really smooth shaved down shroud of the fan check out as the air right about now there it is you can actually see it you can see the air being pushed in hitting this little kind of a ramp and coming back towards you immediately check this out loo that you see it you can visibly see it if we look at it in real-time look at the air as it hits the blade and it's just bouncing right back out comparing with the tape once again in super slo-mo you don't actually see that happening you can see that of course as I mentioned there is some rebound effect that happens when you have pressure in front of a fan or resistance in front of a fan but you can see it's happening a lot less now I should have separated these fans with tape down the middle as well because we are getting some of this effects still happening right here which is causing both of these fans to slam air together as the air is coming off each of these fans the blades are turning technically opposite direction these blades are coming up while these blades are coming down which is causing a little bit of turbulence right in front of it and you can actually see it right here you can see how some of the air is kind of reacting like whoa that's weird so it's really drawing in more on the sides of the radiators with this particular test so it should have been something that I did it was kind of neat though to see how the air responds differently though towards the side of the taped off fans versus the center of them not being taped off at all now I did do all of the testing that you just saw with no fans on anywhere in this room the vents and the air conditioning system were turned off in the house there was no contamination of airflow by any overhead vents or fans or anything like that something else I want to say is that the temperature differences were negligible there were no difference what so ever between tape on and tape off when I ran be a 264 test and a reason for that is because we actually have more heat capability of the system as a whole with the 280 red then the amount of heat is being put into the system by the overclock 59 30 K I said in previous videos and I've shown this before that the size of the radiator is more important the fans that are actually on the radiator because you can have an undersized radiator and put the best fans in the world you're still going to deal with heat soak so I'm pretty confident that the 280 on here could handle all of the heat being put into it no matter what fan I put on here and the differences would have been pretty negligible so perhaps a better follow-up to this video would be doing the same exact test with the 120 millimeter CPU cooler which is on the edge of having enough heat capacity to cool a 59 30 K that's overclocked and do everything we just saw over again and do a follow-up to this I'd be a good test but the whole point of this though was to see if whether or not I was crazy or if there was indeed air coming back towards the intake side of the fan more so than I would normally feel with a standard traditional fan shroud and I think the paper showed that I'm not crazy that that is actually happening I'm not saying it's a bad fan design I'm sure EVGA has a reason why they did this I would really hope that they could come out with some documentation of why they did it and what some of their findings were because I think it would be a good piece to the puzzle trying to figure out why they did this fan shape to begin with there's no literature on it with the CPU cool or anything so anyway thanks for watching guys hopefully you learned something today the very least you got some cool looking dramatic video of how air reacts and responds to fans and pressures and back pressures radiators and all that stuff if you've got a cool idea for a science experiment you want me to do make sure you put it down in the comments or better yet come over and tell me at twitter and if you guys are new around here make sure you hit the subscribe button for more crappy videos like the one you just saw right here and anyway that's it I'm done talking now I'm going to go see you guys in the next one