Same performance according to Cathar, better fit around 1/2" barbs.
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Same performance according to Cathar, better fit around 1/2" barbs.
It depends on the amount of tubing and velocity of water going through the tubing.Quote:
Originally Posted by ANDREW76
In an average setup, there is no real performance difference between 7/16'' ID and 1/2'' ID tubing.
At 1.5gpm with 6ft of tubing (average guess i made) here is the head loss
7/16" = .69768ft of head
1/2" = .36433ft of head.
so at 1.5gpm its not bad at all. so if yo u want to go with something a little more flexibible its not gonna hurt you
now at 2gpm with same tubing lenght
7/16" = 1.1879ft of head loss
1/2" = .62035 ft of head loss
now at 2.6 gpm with same length
7/16" = 1.93016ft of head loss
1/2" = 1.007938 ft of head loss.
so unless you have an iwaki, and ur pumping greater than 2gpm you should be fine with 7/16.
Is there a good place to find 7/16"?
USPlastics.com has it, but it's like $13 to ship 10 feet. lol
mcmaster. :D
Remember Maxxx to account for the tubing ID to fitting ID step-down transitional resistances that occur at entry points to blocks, pumps, radiators, etc. Once these are factored in the differences between 7/16" and 1/2"ID tubing closes right up.
cathar, that math right tere was merely from tubing and nothing else.
but i do see your point about the transitional resistance. this is why i think it is absolutely retarded hat companies use fittings that OD's fit perfectly inside of the tubing. this is also why i try to use 5/8 fitings wherever I can to reduce what you reffered to as step-down transitional resistance.
hmm.. time to do some pressure drop testing with fittings i think.
I know this is a rather odd thing to be picky about, but why is it that swifty always shows the example setup with about 1 foot of extra tubing compared to what it really could need. no sense in extra tubing i think.
Okay, the recommendation goes like this:
People should really be using 7/16" ID tubing with a 3/32" wall thickness for a 5/8" OD.
The physical benefits for 7/16" ID over 1/2" ID are these:
- 7/16" is more slender (5/8" OD as opposed to 3/4" OD). Less bulk equals better case air-flow.
- 7/16" is just as kink resistant as 1/2" ID (3/4" OD) tubing. It will turn just as tight radii, but consume less space when doing so because it is not as bulky
- 7/16" tubing takes about 2/3's the effort to bend as 1/2". This is important for waterblock mounting. Tubing that requires less effort to bend won't be applying as much torque against the waterblock mount against the CPU, resulting in better mount consistency, and therefore better temperatures.
- 7/16" tubing, when filled with water, is 2/3's the weight per unit of tubing length as 1/2" tubing. This means that there is less weight dragging off fittings. This is specifically important again for reducing the rotational torque that tries to tilt the waterblock away from the CPU, again helping to improve waterblock mounting.
- 7/16" tubing costs about 2/3's as much per unit length as 1/2" tubing.
Now people will want to know about how to use 7/16" ID tubing and the flow-rate penalties associated with it. The thing here is that it is quite easy to stretch 7/16" ID tubing over regular 1/2" OD hose fittings, and this is how it should be used. Do not attempt to source 7/16" OD hose fittings, it MUST be used by stretching it over your standard 1/2" OD fittings, and here's why.
This is where we get into the flow-rate effects of 7/16" ID tubing as opposed to 1/2" ID tubing. Aside from the flow-resistance effects of waterblocks, radiators and reservoirs, there are two main types of tubing based flow resistance in a water-cooling loop.
1. The resistance offered by the tubing itself
2. The resistance offered by the fitting interfaces where the ID of the tubing has to step-down to the ID of the hose barb.
Now 7/16" ID tubing is going to be more restrictive than 1/2" ID tubing naturally, however point 2) above is important to consider. When the ID's between the tubing and the host barb more closely match, then the flow resistance offered by the step-down in side is reduced. What this means is that 1/2" ID tubing will offer more flow resistance at barb fitting interfaces than 7/16" ID tubing. How much more? Let's explore that using a good pressure drop calculator.
First let's define what a typical water-cooling setup looks like. Let's assume 2.0m of total tubing length, and a cooling loop that has a radiator, a CPU waterblock, a pump and a reservoir. There is a total of 4 tubing-to-fitting step-down transitions in such a setup. 1/2" OD barbs will have an ID of 9.5-10.5mm, so let's assume a middling value of 10.0mm ID for the barb.
So using our calculator, and 26C water, we arrive at the following flow resistance values:
4LPM
2m x 1/2" tubing resistance = 0.09mH2O
4 x 1/2" ID tubing to 10mm ID fitting resistance = 0.12mH2O
2m x 7/16" tubing resistance = 0.18mH2O
4 x 7/16" ID tubing to 10mm ID fitting resistance = 0.07mH2O
Total 1/2" loop tubing/fitting resistance = 0.21mH2O
Total 7/16" loop tubing/fitting resistance = 0.25mH2O
6LPM
2m x 1/2" tubing resistance = 0.20mH2O
4 x 1/2" ID tubing to 10mm ID fitting resistance = 0.28mH2O
2m x 7/16" tubing resistance = 0.39mH2O
4 x 7/16" ID tubing to 10mm ID fitting resistance = 0.16mH2O
Total 1/2" loop tubing/fitting resistance = 0.48mH2O
Total 7/16" loop tubing/fitting resistance = 0.55mH2O
8LPM
2m x 1/2" tubing resistance = 0.33mH2O
4 x 1/2" ID tubing to 10mm ID fitting resistance = 0.49mH2O
2m x 7/16" tubing resistance = 0.68mH2O
4 x 7/16" ID tubing to 10mm ID fitting resistance = 0.28mH2O
Total 1/2" loop tubing/fitting resistance = 0.82mH2O
Total 7/16" loop tubing/fitting resistance = 0.96mH2O
10LPM
2m x 1/2" tubing resistance = 0.52mH2O
4 x 1/2" ID tubing to 10mm ID fitting resistance = 0.77mH2O
2m x 7/16" tubing resistance = 1.04mH2O
4 x 7/16" ID tubing to 10mm ID fitting resistance = 0.44mH2O
Total 1/2" loop tubing/fitting resistance = 1.29mH2O
Total 7/16" loop tubing/fitting resistance = 1.48mH2O
Now what we're looking at here is the resistances being offered by the tubing and fittings, and not the additional resistances being offered by the waterblock, radiator and reservoir. Let's now add on the resistance of a waterblock and radiator. We'll use a medium pressure drop like the White Water (reviewed by Bill Adams here), and the Thermochill 120.2 radiator (also reviewed by Bill Adams here). We'll assume that the pressure drop offered by the reservoir is neglibible.
Total System Resistance
1/2"
4LPM 0.82mH2O
6LPM 1.80mH2O
8LPM 3.10mH2O
10LPM 4.80mH2O
7/16"
4LPM 0.86mH2O
6LPM 1.87mH2O
8LPM 3.25mH2O
10LPM 5.00mH2O
Now flow-resistance is proportional to the flow rate squared. Therefore with the slightly higher flow resistances offered by the 7/16" ID tubing we can predict what the flow rate impact would be, which is the square root of the pressure ratios:
4 LPM => -2.5%
6 LPM => -2.0%
8 LPM => -2.5%
10 LPM => -2.0%
Now in all of that there has been some approximations by eyeballing graphs, but it's working out that there is about a 2.25% reduction in flow rates by going from 1/2" to 7/16" ID tubing. If we then factor in that centrifugal pumps actually push higher pressures as flow rates are reduced, then we can pretty safely assume that we'll see a net 2% reduction in flow rates.
So basically what we're seeing here is that we'll get 98% of the system flow rates with 7/16" ID tubing stretched over 1/2" OD barbs, as we would get with 1/2" ID tubing over 1/2" OD barbs.
In terms of an actual performance difference, we're talking about around a 0.02-0.05C performance loss at the CPU waterblock due to the decreased flow rates, but this is typically offset by the waterblock being able to make better contact against the CPU due to 7/16" ID tubing's benefits as noted at the start of this post.
In all of this, we can conclude that 7/16" ID tubing, for all intents and purposes, is the performance equal of 1/2" ID tubing, but offers a host of other benefits that makes it much more suited for a top-end performance rig than 1/2" ID tubing.
Oh really?Quote:
Originally Posted by MaxxxRacer
I can't find 7/16ID / 5/8" OD Tygon there.
http://www.mcmaster.com/ctlg/loadpag...n+R3603+Tubing
Only lists 3 tubings with 7/16" OD, none with 7/16" ID.
ill find it for you tonight. if there is a size they dont have I'll pass out.
I must say I am impressed by this kit, nice block, nice pump, nice everything, even the price is right. Hopefully some sites will review the kit shortly (against some euro kits) and let us europeans, see the errors of our ways :P
does anyone know how this block stacks up against the TDX series? From the little reading ive done, it looks to me that the storm would be the best possible choice for a CPU water block atm.
this is the tubing i use from mcmaster, its cheap and bends well enough for me.
part # 5233K44
The Swiftech Storm G4 is based off Cathar's Storm G4. So as it is, this is the best retail block available. The only better block out there, Cathar's Storm G5, isn't readily available and is made in limited batch runs and costs about 2.5 times more.Quote:
Originally Posted by Frambosie
Here ya go, Tygon 7/16.Quote:
Originally Posted by Psyche911
I haven't been following the redesigned Radiator discussions. How well should this new Swiftech radiator perform? Anyone have any guestimates as to where it falls in the performance lineup?Quote:
Originally Posted by MaxxxRacer
So what if you are actually using 5/8" o.d. barbs? Do you guys use 1/2" i.d. tubing for those? Also, anyone have any problems with tubing splitting when stretched that far? I am building up a system with all 5/8" o.d. barbs wherever possible, so for interconnects between two 5/8" barbs, should I pick up some 9/16" i.d. Tygon or just stretch the 1/2" over them? I figure if you are connecting to two 5/8" barbs, going up to 9/16" tubing will only help flow. Then when there is a 1/2" barb on one end use the 1/2" tubing. Sound good?
cart, if your going 5/8 barbs, why not go 5/8 tubing. its what i have on some of my stuff. its pretty darn big, but i dont use a case, so i dont really care.
but on some of the stuff i have 1/2" tubing going to 5/8" barbs becuase on one end of the tubing its 1/2" barbs and the other is 5/8".
Brit, no testing or discussion done outside of Swiftech's labs. but apparently there has been ALOT of testing of that radiator in the lab.
Yeah 5/8 tubing would work too, I just though 9/16 because the barbs on my mcp-650 are pretty tight with 1/2" so 9/16 would probably work fine on it. Plus the 9/16 is way cheaper than the 5/8 Tygon.
Isn't it about same FPI as BIP.... wouldn't be surprised if Swiftech outsourced HWLabs to do the job :P
more FPI = bigger surface area more restrcitve airflow.
less FPI = smaller surface area better airflow.
It's just balancing act for fan noise vs cooling. :)
That is an interesting point Stew that I had not considered. Being an RF/antenna eng. by trade I can see the direct analogy to transmission line impedance mismatch, discontinuities, and VSWR.Quote:
Originally Posted by Cathar
Jinu, I doubt this design was one of HWLabs, UNLESS it is one of the new XFlow radiators from them to be released soon.
and the BIP has the same FPI as the BIX. 18 I believe. Its In my CoolRad 12-T review on the front page.
I would consider 7/16 tubing, but Ive got 5/8" OD barbs on everything except the Fusion GPU block, plus it would be almost impossible to get the tubing on the 18mm barbs of the RD-30, that is the biggest issue for me, it is incredibly hard to get the 1/2" on there...
One thing i don't understand is the c/w rating
they say their's is H20-APEX 1 radiator x 2 120mm fans at 12 Volt 100 0.125 ~37
But i found this review on the xp90c 4870 rpm, 78 dBA² 25.5 C 19.2 C 6.3 0.11 21 C¹
Does the xp90c cool better than this wc setup?
You have 5/8" OD barbs on your G5? If so...pm me please. :slobber:Quote:
Originally Posted by nikhsub1