Research by the cubic foot (ME)

Wayco Wayne_2

Interesting

I've always been frustrated by the lack of clear skys here around Wash D.C. as I used to star gaze a lot when I was younger and would go camping where you could see the Milky Way. Now I can see that this is mankinds way of keeping things warm by preventing night sky re-radiation. You've changed my perspective on pollution by golly. (not really). . WW

To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

ALH_3

What's the objective of this experiment?

Maybe I've showed up to this thread a little late, and it's a little difficult to follow, but I don't understand what this experiment is proving. R and U values refer simply to conductive heat transfer. The time factor, which has been mentioned before, is very important. The incidence angles are continually changing. There's far too much going on at once here for me to decipher the numbers.

Air infiltration is important. Thermal breaks are important. R/U-value is important. Windows are important. Without heat input everything will eventually reach an equilibrium temperature. We're really just trying to slow the loss(or gain).

This might be getting to the point of why the bubble wrap insulation doesnt work under slabs, even with the foil face. It's incredibly ironic that most radiant panels utilize aluminum of some sort for heat conduction, while some insulations use it to resist heat transfer. Without an air gap, the foil does nothing. There's no radiation when the materials are in contact.

I'd love to see dimensionally identical structures built in different ways studied. How much difference do stressed skin panels make? What about a 1/2 inch layer of foam over the sheathing? Icynene? Urethane foams? Fiberglass batts? There are hundreds of combinations. Some problems require empirical solutions. Thermal images would be cool.

I guess I'm saying i dont see the objective of this experiment. How can you find anything if you dont know what you're looking for? In school, teachers emphasize using a given:, find:, solution: format. If you don't, you get lost and never solve the problem. Maybe I'm just missing the point.

-Andrew

Mark Eatherton1

Thanks Tim!

And thanks a million for your assistance the other day. You're a valueable asset to the Uponor group.

Can you imagine the net effect of night sky re-radiation on a snowmelt slab that's being idled???

It's expensive enough to run a snowmelt system, much less having your losses compounded by N.S.R.R..

Thee needs to be a sensor...

ME

Mark Eatherton1

The objective was

to see how the temperature inside the box trails the ambient temperature. Key word "was"...

The inside box temperature didn't trail the OSA temp as one would have thought. At night, it dropped below ambient, and stayed there. Spooky huh...

There doesn't have to be a "goal" in order to do experimentation. Especially if you have an inquiring mind and want to "see what happens if", which is essentially what I did an do. If you never try, you'll never know.

Science is not as cut and dried as you imply...Sometimes, you have to read between the lines.

JMHO

ME

PJO_5

Beers Law

Mark,

Very cool stuff...like S. Ebels I am way in the back of the class trying to keep up. I am interested to see the lag using thermal mass. Also, I would love to see you add varying colors in addition to the "Duncan" model to see the affect on solar gain and NRSS.

And here I thought Beers Law was something like;
If you drink some beer you will feel good...if you drink too much (hard to do IMHO), then you may not feel so good.

Beer is good - in fact it is great...one of man's greatest inventions (I disregarded the results of the "Ten Best Inventions" thing I saw - beer wasn't on it!).

Always learning here...

Take Care, PJO

jp_2

science is fun

""" How can you find anything if you dont know what you're looking for? In school, teachers emphasize using a given:, find:, solution: format. If you don't, you get lost and never solve the problem. Maybe I'm just missing the point."""

andrew, thats the best part about science, you don't always know what you'll find when you go exporing! lots of our physical laws were stumpled upon and not being sought, like x-rays.

jp_2

which hobo

mark, which hobo do you use?
I just found the site, looks like lots of neat toys!

never mind I fouind it! the h08-004?

Tim Doran

Very Interesting

Thanks for the kind words Mark!! Always happy to help.

I have been on a mission to take apart much of the ASHRAE stuff and to dump it into spread sheets. I have been into the snow melt info on and off for a while now and one of the calculations has to do with exactly this situation. Once a storm blows through and a clear, black night sky appears area's of the slab that are not covered by snow will have a significant increase in output and could potentialy rob energy from area's that are still trying to melt. Really interesting stuff although I still struggle with the practicle application of it.

Tim D.

ALH_3

Agreed

I didnt mean to imply this experiment isn't interesting or potentially useful and informative. I'm just looking for conclusions to draw from this.

-Andrew

Boiler Guy

I agree

> I didnt mean to imply this experiment isn't

> interesting or potentially useful and

> informative. I'm just looking for conclusions to

> draw from this.

>

> -Andrew

Boiler Guy

I agree

with ALH This is interesting stuff! But Mark I think you have too much time on your hands out there in Denver. Here I sit at home with a broken leg and can't find time (or is it inclination) to read whilst you are out there working and re-inventing stuff. Keep up the good work while I TRY to keep up with you intellectually.
If you are so inclined, can I interest you in trying to determine the heat of absorbtion left in a -46 northwest wind on a bald snow covered prairie.
The perks are: a blazing fire, a warm bed, hot meals and all the cool "antifreeze" you can "absorb".
Interested??