Barrel coatings test

hobot said:

Well what's your guess on the worth of Sir Eddie duct work for salt lake runs?

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I don't know, but I will probably find out. [since it's setting in my shop]

In your shop is only thing that made sense of your remark. Its on my mind so open to both its worth and how to mimic in water cooled Peel. I was feeling stupid guilty to remove Peel Swain coat for bright highlights so now I look forward to it.

Float like a butterfly but radiate like an ant. Says the ants use a coat of uniquely shaped hairs to control electromagnetic waves over an extremely broad range from the solar spectrum (visible and near-infrared) to the thermal radiation spectrum (mid-infrared) Worth 30 F less in full sun.

Read more at: http://phys.org/news/2015-06-saharan-si ... y.html#jCp

comnoz said:

I don't know, but I will probably find out. [since it's setting in my shop]

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Jim what event do they plan on running? Bub?

Hortons Norton said:

comnoz said:

I don't know, but I will probably find out. [since it's setting in my shop]

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Jim what event do they plan on running? Bub?

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Yes, Bub or whatever the name is now. Jim

hobot said:

Float like a butterfly but radiate like an ant. Says the ants use a coat of uniquely shaped hairs to control electromagnetic waves over an extremely broad range from the solar spectrum (visible and near-infrared) to the thermal radiation spectrum (mid-infrared) Worth 30 F less in full sun.

Read more at: http://phys.org/news/2015-06-saharan-si ... y.html#jCp

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"...where they (the hairs) serve as an antireflection layer that enhances the ants' ability to offload excess heat via thermal radiation, which is emitted from the hot body of the ants to the cold sky. This passive cooling effect works under the full sun whenever the insects are exposed to the clear sky."

Maybe we should be looking at surface texture, rather than the color of paint! It's already known that a rough finish will reject heat more readily than a polished surface. How about a paint that contains the hair harvested from these ants? (joke) Seriously, nanotubes or similar microstructures added to a liquid binder (or powder-coat) might be made that would mimic the effect.

You go, Steve

Who know how to apply fiber antenna radiators to our clunkers but maybe almost nano size holes would work too. Its been known for decades that insects pits and grooves and hairs are tuned for IR and some microwave which is used mainly to detect sex orders by the single molecule and follow the trail so also get confused attracted to warm pavement and equipment. So new age solid state antenna are based on what insects use. I think Peel might have enough water tank 1/2 gallon to both spray cool intake as well as head for the length of normal events.

One thing I looked into are heat pipes which could reach to hottest innards like comnoz temp sensor but no off the shelf fit for us and i am not going to attempt my own but maybe someone will be restless till they do.
https://www.google.com/?gws_rd=ssl#q=ho ... pipe+works
The advantage of heat pipes is their great efficiency in transferring heat. They are actually a better heat conductor than an mass of solid copper.

Thanks Jim- I enjoyed reading this and looking at the movie tests. Just about to coat my cylinders, so useful. I will use VHT again...
When you do these videos I always pause and look around your shop to see all the cool things you have in the background

Jerry

needing said:

Hi texasSlick.
Re: "...Any coating is expected to be only 0.002 inches thick...".
Please review for powdercoat (as it is not a fluid based coating) applied to Norton barrels.

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I have just seen this comment directed to me.

Powder coat is likely to be thicker than 0.002", and moreover, when applied to a body with deep fins like a Norton cylinder barrel, is likely to be very thick in places, and very thin in other places owing to the difficulty (perhaps I should say near impossibility) in getting uniform electrostatic attraction in such a body. Powder coat is very likely to smooth out the surface roughness that enhances convective heat transfer. For these reasons, I would strongly advise anyone against powder coating air cooled cylinder barrels.

Slick

Comnoz has proven any coating even thick power coating does not matter a whitworth to road going heating only land speeders and road racers in summer time. To get a bit more cooling have it all sand blasted raw metal. To get more than that drill as many holes as possible in same dia. as the metal thickness which adds surface area not steal it. To get more than that requires ducting and then coolant sprayed on.

Heres a cylinder that maybe should be tested? 8) Lighter weight and better cooling?

http://www.ebay.com/itm/NORTON-DOMINATO ... sb&vxp=mtr

If that doesn't bring hobot in out of the weeds, nothing will.

:mrgreen:

Great for weight reduction but very likely counter productive for heat loss. :lol:

Dances with Shrapnel said:

Great for weight reduction but very likely counter productive for heat loss. :lol:

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Thats what I was told some years ago. The gents theory was it disturbed air flow. Another theory is simple reduction in heat dissipating fin area. What's yours?

Aside from the obvious that the air tends to flow sideways rather than up and down, holes might have some utility when stuck in traffic and the engine can only cool through convection (up) but that is a stretch.

Taking a simplistic look at it, the surface area of a cylinder (hole) is less than that of the surface area drilled out up until some depth of hole. Furthermore, one is replacing two surfaces (upper and lower) with one cylindrical surface. Do the math and solve for length (L) to see what that point is for a given hole diameter (D). I think it works out to the hole length needs to exceed 1/2 the hole diameter before a hole has greater surface area than two disks and from what I see in the referenced picture above, the hole diameters are much larger than the thickness of the fins.

From a pragmatic standpoint, take a look at all the high performance engineered and designed air cooled engines (aircraft and others) and non of them resort to drilling holes through cooling vanes. This practice seems to be limited to hobbyist and garage mechanics.

In a couple of PM's with hobot on this subject yesterday I pointed out that (in my opinion) drilling cylinder cooling vanes for additional cooling is a solution hunting for a problem in most cases. Typically greater heat capacity on air cooled engines is handled through ducting more air, additional oil capacity and/or oil cooler.

Dances has it right. The break-even point for surface area is when the diameter of the hole is twice the thickness of the fin. A lot of work to drill all those ~1/4" holes, and not really much weight saving. Some more info on that here

holey-cylinders-batman-t7432.html

Ken

lcrken said:

Dances has it right. The break-even point for surface area is when the diameter of the hole is twice the thickness of the fin. A lot of work to drill all those ~1/4" holes, and not really much weight saving. Some more info on that here

holey-cylinders-batman-t7432.html

Ken

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I've seen a 650ss that was drilled something like that, less than 1/2" for sire

lcrken said:

Dances has it right. The break-even point for surface area is when the diameter of the hole is twice the thickness of the fin. A lot of work to drill all those ~1/4" holes, and not really much weight saving. Some more info on that here

holey-cylinders-batman-t7432.html

Ken

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I think it needs to be tested! :? There is alot that might come into play that is not at first intuitive( admitted poorly trying to imitate Hobot writing skills :lol: )

Jim?