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Thread: Thermal Conduction Questions??

  1. #1 Thermal Conduction Questions?? 
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    This insulation company have made claims of R-15 per 5mil thickness for their coating product.

    I feel they are playing fast and loose with the R-value claim.

    Ceramic Space shuttle tiles are R-50 / Inch. At R-15 / 5mil that's R-75 / Inch, They quote the cost for 5 Mil at .35 cents / Sqft, that would be $1.75 / Inch ??......

    I thought That these low resistance numbers were primarily from the vacuum spaces, I can't see how the molecular vibrations responsible for conduction are less in a paint binder than the matrices of the Shuttle's ceramic tiles??

    They claim that their low conductance is due to the The Knudsen effect ....that was new to me.... but makes sense. http://www.industrial-nanotech.com/howitworks.htm , But they still obfuscate about publishing U or R values.

    Why can't this company have these numbers, U and R-values, verified by the government labs or construction product testing institutions?

    That would end this discussion.

    They claim That Aerogels are the only material that has a lower conductance, but

    Aerogel Panels http://www.kalwall.com/nano1.htm are R-20 @ about 2 inch thickness.


    However, This other Nano insulation company has no problem claiming a r-value of R-40:

    http://www.nanopore.com/thermal.html


    Please, I need some thermo dynamic help here.

    Erich J. Knight


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  3. #2 Correction on R-value 
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    The http://www.industrial-nanotech.com/howitworks.htm page shows R values of 10 - 13 per inch which does not seem to be quite as unreasonable as I thought. The R-15/5mil number I posted was found on a stock discussion forum, second hand, repported from a company officer, he was obviously off base.

    Aspen Aerogels has a good technical discussion on this subject that clears up at least some of my questions. Here's the link:

    http://www.aerogel.com/features/termal.html


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  4. #3 told off By the inventor of Nansulate 
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    Well I have been told off By the inventor of Nansulate coating (Hydro-NM-Oxide), Stuart Burchill. http://www.industrial-nanotech.com/howitworks.htm

    I understand my mistaken assumption, exponential, not arithmetical.

    I still don't understand what precludes them from stating a properly exponentially calculated R-value per the suggested 5 mil thickness from their data :

    Nansulate:

    Test Method: ASTM C-518

    Sample Thickness = 0.048”

    Thermal Conductivity = 0.058 Btu/hr ft °F

    R-Value = .048/12(.058) = 0.069 hr ft² °F/Btu

    t-mean = 170 °F




    "Dear Erich,

    Regarding your post of poorly interpreted data, scientifically incorrect conclusions, and the rapid further incorrect extrapolations.

    (Excerpts from Erich's Post to message board

    “No wonder they don't post this on their web page! This

    puts the R-Value of their suggested application rate

    of 5 mils at R-0.28 or R- 1.4 per inch.

    Yet they do post the R-10 value/inch of the pure nano

    material (Hydro-NM-Oxide).which they use in the

    coating formulation, At best this is misleading.


    In her email I was warned not to repost this

    information, I called her back and got permission, and

    am now waiting for a call from Mr. Stuart Burchill

    (inventor/CEO) to explain to me this playing fast and

    loose with how they present the product.”



    A rudimentary understanding of thermal conductivity is clearly not integrated into the thought processes of your posts.


    1) Basic Fact of Thermal Dynamics 101: The thermal conductivity (K value) of any given material increases with temperature.

    2) Therefore… the thermal conductivity of the section of insulation material closest to the heat source is higher than the thermal conductivity of the section of the material furthest away from the heat source. As the heat energy moves through the insulation, it is reduced, therefore each subsequent section is “dealing” with a lower heat energy, or temperature, and therefore the thermal conductivity of that section is lower (per fact 1) and therefore even more effective and reducing the rate of heat transfer as the heat energy moves to the next section which then deals with an even lower heat energy (temperature) and therefore is dealing with it with an even lower thermal conductivity (lower rate of heat energy transfer) and the process of heat reduction goes on exponentially, not arithmetically, as it moves through

    3) Therefore… the R-Value, which is a factor of distance (thickness) divided by K (thermal conductivity) is actually the distance divided by the average sum total of the decreasing K values which occur as you move from the side facing the heat source to the other side of the insulation.

    4) Therefore you cannot correctly extrapolate a comparative R-Value against insulation that has to be applied more thickly from a thin film thickness. If you just take a moment to think it through logically… how much insulation effect would you get from a 5/1000 inch thick section of R13 fiberglass batting or polyurethane foam? Try it, if you can even slice it that thin.

    5) In addition, your calculations do not take into consideration other factors of the physics of heat transfer including emissivity.

    6) Bottom line… you don’t understand how we do what we do and that is understandable. Most people don’t. What is not understandable is that you take data and a field of science that you don’t understand and draw incorrect conclusions and then post them as fact.

    In addition, the test data you were provided is from one of my original formulations and is dated September 21st, 2004. I have not been sitting idle since then and have continued to improve performance.


    I tried to call you, but got your home answering machine.

    Instead of trying to look for problems and creating them where there are none with your misinformation dissemination, why don’t you tell a friend or a neighbor about our great products THAT HAVE STOOD THE TEST OF TIME AND PROVEN THEIR PERFORMANCE IN THE LABORATORIES AND ON THE PRODUCTS AND FACILITES AND RESIDENCES OF GREAT COMPANIES AND GREAT PEOPLE WORLDWIDE AGAIN AND AGAIN AND AGAIN?

    Stuart Burchill
    Industrial Nanotech, Inc. "








    Erich J. Knight
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