Flow dynamics of a drain line?

[sswilson]

I'm planning out the loop on my latest build, and since this is my first WC'd vid card it's opened up some possibilities I haven't had with previous loops so I wanted to pick the brains of folks who've been there before, or possibly who might have formal training in flow dynamics.

Seems like a simple task, as per the image above I'm thinking about adding a tube with a ball shutoff valve to one of the lower vid card block ports which would make draining the loop super easy, and also allow me to do so outside of the case without actually having to disturb any of the loop components. What I'm concerned about is if having what is essentially a res at the bottom of my card's WB is going to have an adverse affect on flow through the block or (like a closed hydraulic loop) will it effectively "invisible" to the loop once it's full?

Any ideas?

[enaberif]

Best place for a drain tube is immediately after the reservoir otherwise you always fight for the liquid to come oi5.

[brewer265@]

Best spot for a drain is at the lowest possible spot. Like enaberif suggest is where i have my drain lines. I use a t off of one of the ports on my reservoir. Drains super fast.

[sswilson]

Because I'm using a bay res, the point I've selected is the lowest point in the loop.

[KaptCrunch]

never run pump to drain

as rest said lowest point of the loop and a bleed air from the highest point in loop to drain fully

[sswilson]

Maybe I'm not explaining my loop well enough.......

top rad,5 1/4 bay res/pump combo, cpu block, vga block.

As it stands, the lowest point in my loop is the bottom port(s) of the VGA block (designed for SLI) and I can open the fill port on the res to provide open air to ease the flow. I'm not talking about running a pump to drain it, and the VGA is going to be feeding the res so in all honesty, the opposite side of that fitting is the same as the lowest port of the res only lower.

Now onto the question I'm wondering about.... on a 4 port VGA block without sli, will having a 6" tube on one of the rear ports (for SLI and thus would normally just be plugged) with a plug and/or draincock (closed except for draining loop) affect the normal flow of the VGA block?

[SugarJ]

It should be fine. I ran a T in the bottom of a loop, and when I added dye I watched it. The fluid flows right by the capped off section as there's no flow, just pressure. It took DAYS for the fluid in the drain line to equalize in color with the rest of the loop.

But like I said in chat the other day, the easiest way to do without a drain or T is to tip the case on it's front (on something soft to avoid scratching). The res becomes the lowest part of the loop, and you drain through the fill port.

[sswilson]

Originally Posted by SugarJ

It should be fine. I ran a T in the bottom of a loop, and when I added dye I watched it. The fluid flows right by the capped off section as there's no flow, just pressure. It took DAYS for the fluid in the drain line to equalize in color with the rest of the loop.

But like I said in chat the other day, the easiest way to do without a drain or T is to tip the case on it's front (on something soft to avoid scratching). The res becomes the lowest part of the loop, and you drain through the fill port.

Cool!!!! That's exactly the kind of hands-on experience I was looking for. :)

I understand the concerns about leaks and am willing to take that risk. :)

[SugarJ]

My original thought yesterday was that you were just going to remove the stop fitting and drain from there, which would spray around a bit. I'd be way more comfortable with a drain tube. I usually make mine long enough to run outside the case.

Edit: Just had a thought. The flow from the opposite port will tend to try to push into that tube rather than make an angle and go through the block. It should be ok once the loop is full, but watch your flow while filling. This is one case where I'd definitely disconnect the CPU and GPU until you know that you've got good flow through the loop. The blocks heat up fast if there's no flow, as I found out the hard way.

[sswilson]

Originally Posted by SugarJ

My original thought yesterday was that you were just going to remove the stop fitting and drain from there, which would spray around a bit. I'd be way more comfortable with a drain tube. I usually make mine long enough to run outside the case.

Edit: Just had a thought. The flow from the opposite port will tend to try to push into that tube rather than make an angle and go through the block. It should be ok once the loop is full, but watch your flow while filling. This is one case where I'd definitely disconnect the CPU and GPU until you know that you've got good flow through the loop. The blocks heat up fast if there's no flow, as I found out the hard way.

Your memory isn't failing you, that was my initial line of thought, but it evolved into a drain tube which should make life a lot easier.