Stovers, Quick question - does radiant heat require the subject be 'n sight' of the object being heated?
Thanks Frank -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Richard Stanley Sent: Wednesday, March 07, 2012 12:27 PM To: Discussion of biomass cooking stoves Subject: Re: [Stoves] radient heat capture, total heat measurement Andrew, Its the old quandry of Brownian movement then, eh ? Still that "sense we an animals all have of "heat' and "warmth " remains well beyond degrees of temperature oer se. Something missing between science and perception that unless clarified and quantified would seem to leaves stove performance assessment abit untidy. Richard Stanley www.legacyfound.org ======= On Mar 7, 2012, at 11:44 AM, [email protected] wrote: On Tue, 6 Mar 2012 07:47:03 -0800, Richard Stanley wrote: > If radient energy is the mother and conductive convective "heats" are added expressions of it, then why does one rely only upon measurement of thermal heat only in these more tangible but not necessarily more influential bands of the spectrum, as the standard measure of cooking efficiency ? I suppose it's to do with what means we have of producing the power to do the cooking, fire is the easiest way of liberating the energy and transferring it to the cooking pot. Plants have concentrated sunlight into wood. Light can plainly be used for heating, didn't one of the ancient greeks write of the concentrated beams reflected from polished bronze shield setting fire to ships rigging? > Micro waves in themselves are not "hot" but they do a wonderful job of heating by disturbing molecules, just as the visible band of radiation we call heat, does. Presumably there was no evolutionary advantage in having an organ that can sense infra red in the same way eyes interpret light but many animals do have increased sense of warmth, snakes can hunt by it. Microwaves for cooking have only become commonplace in the last 60 years but the principle is the same as other means of heating, they selectively excite water molecules. The microwave radiation is tuned to deliver in frequencies which water molecules will accept in discrete amounts, otherwise they would just pass straight through. > My naked supposition is therefore, that beyond a normal thermometer or one measuring just IR, one needs a more comprehensive "molecule disturbing" > measurment device A thermometer is something that reacts to change in temperature, it doesn't measure the activity of molecules but rather compares the effect the molecules have on a substance. I don't think it is possible to directly measure the state of a molecule without changing it. AJH _______________________________________________ Stoves mailing list to Send a Message to the list, use the email address [email protected] 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/ _______________________________________________ Stoves mailing list to Send a Message to the list, use the email address [email protected] 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/ _______________________________________________ Stoves mailing list to Send a Message to the list, use the email address [email protected] 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/
