Liquid Cooling expertise wanted

[RJR]

If it runs through the rad first, there is a pressure drop, if you read about your rad you will find out how much of a drop it has, because differant rad have differant pressure drops, and the water is not moveing as fast after it goes through it,

OK, I'm a little confused here, your saying that the water is moving faster before it goes through the radiator and then it slows down, is that right?

 

See that's the part I don't get since there is already water in the radiator moving slower, how do you get the water before the rad to move faster? Please explain.

 

OK, I finally came up with something:

 

You are driving in a one lane tunnel, you have a bus (restriction) in front of you driving at 55 MPH (the max it can go) and three cars behind it driving the same speed (water in the tubing), you approach them doing 70 MPH so you have a choice, run into the last car or slow down to 55 MPH. Say your in a tractor trailer and don't care about human life and are just in a hurry so you slam into the last car and that pushes it into the next and so on, But your still not doing 70 MPH anymore because of the bus in front so you just keep pushing (water pressure) until your pushing all the cars and the bus too. Can you push the bus a little faster than what it was doing before, sure depending on the pressure you apply to it, BUT are you now going the same speed (water flow) as the bus no matter how hard you push, YES.

 

That's the best I can do without getting into Burnoulli.

[HarryTaco]

RJR think of it this way. It has to do with volume of water. You have a 25ft wide stream that runs water at 10 MPH,, the stream now widens to say 40ft side to side. The water will now flow perhaps 6 mph at the 40 foot wide path. The stream narrows back to 25ft wide and again the speed of the flow is back to 10mph. The radiator widens out, and flows the same volume but at a slower rate. At the exit it again goes to say 1/2 inch id hose and the flow increases back to a higher speed.

[Waco]

Flow has nothing to do with how much water there is It is how fast it is moving.

It has everything to do with it. Since it's a closed system the flow is identical at every fitting. It can't be different without a change in volume somewhere in the loop.

 

If it runs through the rad first, there is a pressure drop, if you read about your rad you will find out how much of a drop it has, because differant rad have differant pressure drops, and the water is not moveing as fast after it goes through it, and temp differance is not 1 or 2 degrees, it is less than .8 degrees.

Again - the water is moving the same speed at any fitting in the loop. Water in == water out for each component. There's no change in speed/flow/whatever except internally on each item and that is completely independent of where that item is in the loop.

[RJR]

RJR think of it this way. It has to do with volume of water. You have a 25ft wide stream that runs water at 10 MPH,, the stream now widens to say 40ft side to side. The water will now flow perhaps 6 mph at the 40 foot wide path. The stream narrows back to 25ft wide and again the speed of the flow is back to 10mph. The radiator widens out, and flows the same volume but at a slower rate. At the exit it again goes to say 1/2 inch id hose and the flow increases back to a higher speed.

Yes, that is true in a river, but is not the way it works in an enclosed system. It would only apply when the system was empty and the water was run through it the very first time, after everything is full of water it can't speed up and slow down because it is pushing the whole volume of water at the same time.

[Waco]

Yes, that is true in a river, but is not the way it works in an enclosed system. It would only apply when the system was empty and the water was run through it the very first time, after everything is full of water it can't speed up and slow down because it is pushing the whole volume of water at the same time.

Exactly.

[Drdeath]

Imo changing the config is not going to change temps. It is a tad better to run pump into. Rad for lil more dissapation.

[Waco]

Imo changing the config is not going to change temps. It is a tad better to run pump into. Rad for lil more dissapation.

Personally I run the rad before res and pump to keep the pump temps down as low as possible though I doubt it makes much difference at all.

[Drdeath]

Personally I run the rad before res and pump to keep the pump temps down as low as possible though I doubt it makes much difference at all.

I do too but the heat dunp from the pump is not a lot. If I remember, I gained a degree or 2.

[Waco]

I do too but the heat dunp from the pump is not a lot. If I remember, I gained a degree or 2.

I do it to extend the lifetime of the pump - I don't really care about that last degree if it makes my pump work harder.

[Drdeath]

I highly doubt pump into rad will have any effect on a mcp655. Dirt is most commonly the culprit of a pump failing.

[Waco]

Yeah, it probably doesn't make any difference. It's my first loop (well, second or third depending on how you count) so I was being anal about it.