Air cooled condenser

[shadylane]

Decided to build an air cooled condenser using five 2' long, 3/4" finned copper tubes from lowes.
http://www.lowes.com/pd_62395-33978-HB- ... umber=0319" onclick="window.open(this.href);return false;" rel="nofollow
I'll be building a header so the five tubes will get equal amounts of vapor.
A cheap window fan will be used for cooling.
The output header will be removable so the inside of the tubes can be cleaned.

[bearriver]

I like the manifold/header idea. Nice plan.

[Kegg_jam]

Neat.

I guess you need two manifolds. An Input and Output for collection.

[shadylane]

Figured to make the input "manifold" I like that term better than header. Out of 1-1/2" copper tubing.
I'll cut a tapered slice out of the tubing, and roll it into a funnel shape so its smaller on one end.
Then I'll braze five pieces of 3/4" tubing to the manifold for connecting the condensers.

[shadylane]

The outlet manifold will be a slip fit. That way it's removable.

[mason jar]

Can't wait to see the results from your build Shady. I like the cone shaped input "manifold".
Looks like that should help to distribute the vapor across the parallel tubes.

[shadylane]

Here's a manifold I made last night. Too bad I'll be scraping it because the so-called bronze rods I used were 59% copper, 40% zinc and 1% iron. The rods were Lincoln electric KH515. Monday I'll go to town and buy some silver brazing rods and do it right.

[still_stirrin]

OMG, shady....you've got some skills!

That header is purdy. I love the gentle taper you've built into it. It adjusts the flowrates at the takeoff points using flow velocity to maximize static pressures. For compressible flows, this should help to balance the flows through the individual HEX lines. Great idea. One thought....a little more taper might even help more (to balance the flows).
ss

[MichiganCornhusker]

If you hooked the manifold up to your elements and ran it without the bottom collector on it might show you how effective the vapor distribution is. Having the bottom collector on there might change that somewhat, but you still might get some useful visual.

Another test might be to put some clear plastic hose between the exits of your elements and the bottom collector, so that you can see what is happening at each output when running. (Just as a proto test, of course, no plastic in finished model.)

[shadylane]

That's a good idea MCH. I might add some scrubbers in the tubes that flow more than the others.
Started building another inlet manifold. I'm making this one a little longer and with more taper.
I cut a wedge shaped piece out of 1-1/2" L tubing then annealed the copper.
Next I bent the tubing so the wedge shaped piece would fit turned around, that added a lot more taper

[just sayin]

Nice craftsmanship, Shadylane! Have you ever tried Harris 0? It is a silverless braving alloy with 7% phosphorus and the balance copper. Reasonable priced, strong and requires no flux, so no clean up. I used it daily for years.

[shadylane]

Haven't tried Harris 0. I was planning on Harris stay-sil 2 or 5
I'll see if Airgas has any Monday, until then I'll file, hammer, grind and drill.
It's probably best that I don't have any usable brazing rods this weekend.
It'll stop me from getting in a rush.

[bitter]

Looking good. When I seen this I was thinking air cooled shotgun condenser.

B

[Jacksonbrown]

Your tapered solution is probably best if it's sized right but a simpler way it just have a large diameter header.
It should give a similar result just with less fabrication (slightly more weight)
The larger the header is relative to the take offs, the smaller the pressure drop will be from the first to the last take off.
Same pressure feeding each one should mean an even split across all of them.

On super long headers I've started on 4" dropped down a size with a reducer every couple of take offs which sounds similar to what you're doing.
I can't remember how it was sized properly (it may have just been arsed) but keeping the vapor velocity the same all the way along the header sounds reasonable.
Lower velocities means less pressure drop which is the real aim.

[shadylane]

Anyone who has tried to drill a big hole in copper knows how difficult it can be.
A 1/2" knockout punch makes a perfect sized hole for 3/4" copper tubing.
Haven't checked to see what tubing or pipe sizes that will match the other knockouts.

[bearriver]

I wanted to say earlier that I think the taper was a great idea Shady.

I've been lightly pondering how to approximate the amount of vapor each tube will get with an equation. It would be nice if each tube received near equal amounts of vapor

[shadylane]

Made the holes in the manifold with the knock out punch. These will be real easy to braze.

[shadylane]

Looking good. When I seen this I was thinking air cooled shotgun condenser.

B

Here's what comes to mind.

[shadylane]

Finished most of the brazing on the inlet manifold, Used harris stay-sil 5 without any flux.
After I build the brackets to hold the mainifold to the fan, I might use flux and reheat all the welds.
That might make then prettier

[Brutal]

Looking good buddy

[shadylane]

Now I've got to figure out how to make an outlet manifold from the same scrap pile that I used for the inlet.
Between shots of sugarhead Rum and puffs off a very offensive smelling cigar, Bubba suggested using an open trough.
That way we could see what each condenser was doing.
With a fan blowing and hot ethanol, that sounded like a good idea for a flame thrower.
Luckily there's a several buckets full of copper fittings laying around.
I think I'll go the easy route and use a 3/4" to 1/2" reducer then use elbows, tee's and soft drawn 1/2" tubing.

[Angel_Kefka]

Looks nice. Can't wait to hear how it works.

One question. The space before the fins start, is it just that big to make the soldering easier? Or did you have another reason.

[MichiganCornhusker]

With a fan blowing and hot ethanol, that sounded like a good idea for a flame thrower.

One person's flame thrower is another person's "speed airing out"

Nice work Shadylane, this is a top notch build.

[shadylane]

Looks nice. Can't wait to hear how it works.

One question. The space before the fins start, is it just that big to make the soldering easier? Or did you have another reason.

That's the way it was manufactured. I didn't have anything to say about that.
Thought about cutting a couple of inches off too make it shorter. But the end was already flared "female"
Don't know how to say it without sounding crude, but when coupling male to female, leaks are less likely when the male is on top.

[shadylane]

Your tapered solution is probably best if it's sized right but a simpler way it just have a large diameter header. It should give a similar result just with less fabrication (slightly more weight)

Your logic is 100% right, but the moonshine said to do it different.

[still_stirrin]

....when coupling male to female, leaks are less likely when the male is on top.

That's exactly the way to do it. When the bell (flared end) points up you won't have a "trough" around the inside of the joint which would, or could, pool liquid. It also is smoother to the flow (less flow resistance).

Gotta say Shady, that is a very fine looking manifold you built. Time spent...was invested wisely.
ss

[shadylane]

Did a little bit of building on the outlet manifold. Haven't soldered any of the joints yet.
I'm not going to solder the manifold to the finned tubes unless I have to.

[Hound Dog]

Roll with it! Can't wait to see how this works. Are you running electric or propane? It would be nice to know how much power it will knock down. All being relative to air temp I suppose.

[shadylane]

I'm running electric. Not sure but after burning out the last heater a 4000w low density Inconel element was used.

[Jacksonbrown]

Your logic is 100% right, but the moonshine said to do it different.

Plus it wouldn't look nearly as cool.
Just make sure it drains OK so you don't get too much pooling in the corners of the header.