Rad's Internal flow

[Exahertz]

Just a simple question. With an MCR320 (or almost any rad) is there an in and out? And what does it look like or how does the water flow inside?

[septim]

from 1 hole end to the other hole end. 2 pass...
either could be inlet and outlet, depending on where you place said rad...

[Martinm210]

MCR320's are single pass, so no it doesn't matter there. But some rads are dual pass (two layers sandwiched together), on those I would probably make the first pass on the downstream air(warmer air) side, and second pass on the coolest air or upstream side.

In the end, I'm not sure that even makes much if any difference though:shrug:

[Waterlogged]

MCR320's are single pass, so no it doesn't matter there. But some rads are dual pass (two layers sandwiched together), on those I would probably make the first pass on the downstream air(warmer air) side, and second pass on the coolest air or upstream side.

In the end, I'm not sure that even makes much if any difference though:shrug:

I think you mean single row. All rad with fittings on the same end are 2 pass.


Exahertz, I hate to use a crappy rad as a guide but this is the best pic I've seen like this.
http://img165.imageshack.us/img165/4813/radlayoutwg5.jpg

The red is the "hot" water, this is pass #1. The blue is "cooler" water, this is pass #2. On this rad (BI GTS), there is only 1 row of tubes, on a BI GTX (the big brother to the GTS) ther are 2 rows of tubes, which makes it much thicker. The Swiftech MCR series rads are similar in design to the BI GTS. There is no in/out.

Only rads with fittings on each end can be either single pass/single row or single pass/double row.

[disruptfam]

will rad type performs better?

single or dual?

i havent seen to many single passed around... so i would assume dual is better? yes/no?

[STEvil]

Depends on what fans you use and how many.

[bobo5195]

might be better to have cold water hitting the cold air. For various complicated reasons if you punch the maths.

Basically a bigger temp delta and a small temp diff is better than average overall.

[septim]

am getting confused on single or dual pass rad... will go researched this up some more...

as long as my basic understanding:
1 barb hole inlet goes to other side rad makes a u-turn and back to other barb outlet.

[Boogerlad]

well, i think that single pass is better because since a wc loop is all filled with no air bubbles left inside, the time spent inside the rad doesn't really matter, because single and dual pass rads have the same contact area between fins (i think) , so less restriction from single pass ftw! correct me if i'm wrong though. i read this in the sticky section somewhere here.

[Martinm210]

I think you mean single row. All rad with fittings on the same end are 2 pass.


You're right, I was thinking along the lines of a single thickness that passes the same location twice, but that's correct!:up:

[Martinm210]

This french article (http://translate.google.com/translate?u=http%3A%2F%2Fwww.cooling-masters.com%2Farticles-38-0.html&langpair=fr%7Cen&hl=en&safe=off&ie=UTF-8&oe=UTF-8&prev=%2Flanguage_tools)talkes about single pass, two pass ect.

Single pass would be an X-flow radiator:

http://www.cooling-masters.com/images/articles/gts240/images/xflow.jpg

Not the easiest reading, but what I understood going through this is that there is a careful balance between restriction and thermal performace. If you make it too free flowing like a single pass radiator that you loose thermal efficiency.

Sounds like the normal 2 pass design is the more well rounded option.

[bobo5195]

If you place two single passs back to back you get a double pass. At least this is the way you model them.

Look at Kays and London (first result on amazon.com) tells you basically how to design a rad and I think it has the graphs for fin spacing vs restriction etc. I had a link to website somewhere with all of this...

I wouldn't say two pass is inherently better than single pass. Two pass should always have more performance (as an extra pass; another radiator is available) how effective this pass is for the cost is the question. As performance increases (lower temperature differential) single pass has more advantages over dual pass. Equally two pass is a relatively cheap upgrade, not quite free but probably very easy on balance.