"Radius" by BigBen2k

[jaydee]

Originally posted by jaydee116
I got SolidWorks 2003 and it lets me save in .DXF format?

Ahhh, scratch that. It will let me save DXF in drawing but not assembly or part. Lots to learn about this software....

[LiquidRulez]

I heard someone say that they can import a SW file into mastercam and export it as DXF.

Dont realy know if it works or not.......I will tomorrow though and Ill let you guys know. If it does Id be glad to convert it for ya's


EDIT

Didnt work but I found a site that tels you how to make a DXF file from a solidworks model..........

LINKAGE

http://psdam.mit.edu/2.000/tutorials...F-Tutorial.pdf

Hope this helps

[bigben2k]

Some interesting progress:
http://forums.overclockers.com.au/sh...postid=1535450

My fellow frenchman has agreed to take a look at Radius, in an attempt to simulate the heat/flow dispersion.

This would be nice...

[bigben2k]

I've got the graphs from Roscal.

First of all, I'd like to take a minute here, to extend a BIG thank you to Roscal: the data that he provided is absolutely fantastic, and I don't believe that Radius could be optimized as much as it's about to be, without his most excellent work.

What follows is some of the graphs that he sent me. If anyone is interested in seeing the whole series, PM me, and I will give you the link to the complete HTML page, complete with comments!

Note: the graphs were based on the latest Radius design, as Utabintarbo put it together. It does not include a nozzle, nor a flow seperator.

Another thank you to Utabintarbo, also for putting up with me and my unusual (Canadian?) wording of some descriptions.

[bigben2k]

First graph:

It is a flow velocity, as noted by the chart.

Comments: because there is no flow seperator, there is a big deadspot, right in the middle. I will be going over some options, and possibly with the help of Jaydee116, I can add a decent flow seperator that'll work. Nozzling may or may not be a factor, I will be going over this as well.

[jaydee]

I can give it a shot. Need pretty detailed info and a good drawing of what it is you need.

[bigben2k]

The next one, also a flow graph, shows that there is a vortex forming, in the outer channel (ring, or toroid).

I should have predicted this. My original idea was to have the outer curve, but not the inner one. The solution I'm thinking about applying here, is to do away with all this curve stuff, and have the outer channel (ring or toroid) completely square.

I never got around to optimizing the outlet, but I have a potential solution to this as well.

This graph also partly shows something that completely blew me away: there is (slightly) more flow in those channels at 45 degrees, than the ones at 90 degrees. The overall speed is pretty balanced otherwise, with fluid velocities reaching 2.5 m/s (assuming a 100 gph flow rate).

From the previous graph, one can also see that there is stagnant flow in the top half of the channels, around the outer edge of the fin pattern. It is not terribly relevant, but I will attempt to add a restriction, from the top, to eliminate this deadspot. Otherwise, the flow is mostly concentrated at the baseplate.

[bigben2k]

This one is a thermal.

It clearly shows (to me) that the fins are absolutely critical. Also, if I interpret Les's latest series of graphs, the more the better (i.e. a bunch of really small fins).

If you look REAL closely, you'll see a hint that the heat extends better through the central four fins, which are the only ones that are connected together. This is by far, what limits Radius from being more effective: disconnected fins. White Water's fins are ALL continous.

[bigben2k]

This last one is a fluid thermal.

With all the issues stated above, it all makes sense.

[bigben2k]

Thanks Jaydee116, I will get you the info that you need.

First, here's a new top outlet opening. (red, solid. yellow: opening). Since this may compromise the top integrity, I'll be going with a thicker top. Those red gaps are 3.5 mm wide. The opening's inner radius is 25 mm, and I'll have to lookup the outer radius.

[bigben2k]

Here's a rough idea of the flow seperator I'm looking at.

The diameter showed here is 5/8 in., but I'll be revising the nozzle size. In short, the seperator will be about 1/2 in. tall, and in the shape of the highlighted area, in blue. It will sit on top of the fins. Since the inlet diameter is 5/8, I'm hoping that I can design a "flow seperator"/nozzle that I can simply drop in the inner tube.

[hara]

What programs were used to simulate the block? Looks interesting.

[bigben2k]

As Roscal wrote himself in the OCAU thread:

The name of the soft I used is Floworks (addon to Solidworks) but now I use Gambit 2.04 + Fluent 6 +Tecplot 9.2 to simulate and do studies about block. It's 100x powerful than Floworks but more complicated

[Paxmax]

Whaat the... ? When I stumbled upon this link I have been doing some doodeling on my PC at night since I couldn't sleep, and I came up with the exact same pic as seen upfront of this link!! Maybe not in fancy colors, but same amount of fins and arranged in the same pattern !!!

My inspiration was this: http://www.overclockers.com/tips977/
Truly a work of art(ist), and it seems to preform!
Well, you guys are well ahead of me, damn, another idea into the bin! Keep up the good work lads!

[bigben2k]

I'll take that as a compliment, Paxmax! I've seen your name on OC several times, nice of you to drop by for a visit! I think you and I may have a similar level of understanding.


One thing I forgot to mention: as per Roscal's own estimation, the block, tested as it is, would be 4 deg C hotter that White Watter.

I'm close, I'm really close...

[Roscal]

Pay attention to what I said BB2K..

I gave you the hottest T° in copper so point in the middle of the die BUT T° distribution isn't equal on the die , it's "concentric" so a T° average (less than higest T°) must be calculated on whole die surface (as BillA die it's not T° constant on the die, in reality it's different because of components into the die, L2 heat more than other die units so T° distribution is "random").
This average could change between 2 blocks... The 4° are not real because it's an savage extrapolation (?) to 70W to 100W I done in my mind (not the real geometry too)

Take care about T° because all is "perfect" in a simulation (no TIM, perfect contact, etc..), depends on my reference too...It's a prediction !!

[bigben2k]

Thank you, Roscal!

I understand that the temperature distribution (or heat source) from the die is not "even", although it is simulated to be that way.

Not to worry, I took your "4 deg C" estimate as a rough estimate. I am assuming that the process that you used to make the estimate, is the same as for WhiteWater, so the results should be "somewhat accurate".

I also understand that this is a simulation, and that there are a number of variables that are not taken into account. As you pointed out yourself, my channels are perfectly square cut, when really, there will be a slight curve, from the wear on the endmill. Also, the center cross is not square cut, there's a very small curve, also as a result of using an endmill.


All: yesterday, I started to work on the geometric calculations of the inlet opening, in order to determine the proper/optimal size of the nozzle. Due to unavoidable circumstances, I won't be able to complete those calculations this week, and next weekend looks grim...

Hang in there... it's coming!

[hara]

Roscal,
According to your initial simulation, what is better? WW or Radius? This would be interesting to see.

[bigben2k]

WW, by 4 deg C. (assuming that the simulation is similar).

[bigben2k]

Here's a pic of the part of the res that was troubling me:

The top (white) piece is the threaded adapter. The middle (grey) is the trimmed polypropylene barb. The bottom is the 1 1/2 clear polycarbonate tube (with electrical tape, to protect it from scratches).

[bigben2k]

...and here's the pic...

[bigben2k]

The polypropylene was (is being) replaced with a nylon one, which glues very easily now.

[bigben2k]

Here's one of the inner tube's elbow, mounted.

As it turns out, my measurements were off: the inner tube (straight) wasn't long enough. It has since been taken apart, and rebuilt (Good thing that Goop is easily removed!)

[nicozeg]

WOW! Those simulations are incredible! Mastering that kind of software is a really powerful tool for the block maker. Isn’t there any “CFD for dummies” one?

Maybe this is too much asking Roscal, but are you interested in doing a simulation for another radial microchannel design I’ve made? I can provide a 3d model in the format you ask me. Details of it can be fount at this thread.

Ben, maybe the water can be forced to that central corner by going deeper with the intake pipe into the base.

[bigben2k]

Originally posted by nicozeg
Ben, maybe the water can be forced to that central corner by going deeper with the intake pipe into the base.

Now why didn't I think of that?:shrug:

[nicozeg]

Adjusting depth and reducing diameter could do the trick, but finding an optimal that doesn’t cause a severe flow drop could be difficult.

To avoid modifications to the main fins it could be easier to cut slots on the pipe end at 45º. The interference with the tips of the third fin level could be milled out in the base, as it doesn’t affect the structure.

[bigben2k]

Yep! It actually takes care of two problems.

I'm still going over the nozzle dimensions, and the inlet/outlet ratio of different areas within the block, to get to an actual nozzling effect. (Not terribly accurate, as it doesn't account for hydraulic equivalents, yet...).

The nozzle was always meant to be a "drop-in" solution, so that I don't have to build a new top each time I want to test a new configuration. With the notches, now I don't have to worry about it spinning out of position.

I'm not too worried about how deep the nozzle can go within the channels: I'm aiming to focus the flow within the bottom half of the channels, so the top half is "free game".

The inner tube's inner diameter (ID) is 5/8 inches. Whatever the solution, it'll have to fit in there.


Another thing that's been bugging me: it seems that people don't get the use of 8 bolts on the top: as Paul Vodrazka put it, 4 aren't enough to ensure an even clamp. That may or may not be true, but I am not a mechanical engineer, so I'm opting for "more than 4". Since 6 is awkward ( 5 and 7 even more so), and would be a hard fit within the confined area of the block (because of the o-ring, which has already been reduced to 1/16, for the same reasons), I opted for 8, spread equally, with a 22.5 degree "twist" to make maximum use of the tiny available area outside the o-ring.

(So Bill, if you're still reading this, it wasn't for aesthetics).

[nicozeg]

Just realized something in your design:

Water always prefer to flow through the wider path. Case 1 is your actual situation, the 1 mm channel at the corner seems too narrow. If you cut the corner of the fin the situation improves a lot, focusing more flow at the key spot. Cases 3 & 4 are just variations.

[SysCrusher]

Originally posted by nicozeg
Just realized something in your design:

Water always prefer to flow through the wider path. Case 1 is your actual situation, the 1 mm channel at the corner seems too narrow. If you cut the corner of the fin the situation improves a lot, focusing more flow at the key spot. Cases 3 & 4 are just variations.

In three I'd make the center fin with more of a longer point to it if at all possible. That way your not accidentally forcing the water past the next fin. Trying to help.

[bigben2k]

That's correct, but if the area of the inlet (or its hydraulic equivalent) is less than the outlet, then the coolant should "shoot" down, hitting the baseplate.

I ran some calculations earlier, and this "ratio" (inlet to outlet) actually varies greatly, from 0.2 to 1.5, for diameters ranging from 0 to 3/4. There's kind of a linear progression, but not completely. It was an old calculation though, based on inlet tube diameter, and exiting channel area.

In the simulation, there weren't any flow seperators, so the coolant hit the top of the fins, instead of the baseplate. The resulting disturbance causes the water to ignore the deadspot, at the corner. If you look at the first graph, you can see a red spot (high speed), righ on top of the fin. I believe that that hot spot actually acts as a flow restriction.

I was looking at this earlier, and if I use a nozzle that's 1/4 inch diameter, that would address exactly what you wrote about. The exiting channel area ratio is favorable (for the water to shoot down). Now I just have to calculate the resulting pressure drop, and recalculate the channel exit's hydraulic equivalent, and double check all my calculations...

Here's a pic of the 1/4 diameter: