[Stoves] radiant heat capture, total heat measurement

[Kevin]

Dear Richard
----- Original Message ----- 
From: "Richard Stanley" <rstanley at legacyfound.org>
To: "Discussion of biomass cooking stoves" <stoves at lists.bioenergylists.org>
Sent: Thursday, March 08, 2012 1:51 AM
Subject: Re: [Stoves] radiant heat capture, total heat measurement


>
> Kevin & Frank:
>
> Can I add my own experience with heating coffee  in our microwave ?: 
> Certain iron rich clay cups will get hot as heck with luke warm coffee 
> inside, while the other more "pure"  clays and glass cups don't --while 
> their contained coffee rises to near boil in 30 odd seconds. U wave bands 
> are admittedly  not in the IR band widths but it seems to offer a certain 
> parallel here, in the discussion of emissivity/ reflectance, or no ?

# I think there is a very simple mechanism at play here.... It is not so 
much the "iron rich clay" that makes the cup get hotter than the coffee, but 
rather, that the clay from which the cup was made is porous, and has 
absorbed water from soaking in teh sink, while being washed. As an 
experiment, take one such cup, that heats up, and put it in a conventional 
oven for a period of time (several hours) to dry it out. Then repeat the 
test in the microwave, and see if the body of teh cup gets hot.

Best wishes,

Kevin

> Richard Stanley
>
> _______________________________________________
> Stoves mailing list
>
> to Send a Message to the list, use the email address
> stoves at lists.bioenergylists.org
>
> to UNSUBSCRIBE or Change your List Settings use the web page
> http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists.org
>
> for more Biomass Cooking Stoves,  News and Information see our web site:
> http://www.bioenergylists.org/
>
>
>
> -----
> No virus found in this message.
> Checked by AVG - www.avg.com
> Version: 2012.0.1913 / Virus Database: 2114/4856 - Release Date: 03/07/12
>