<html><head><meta http-equiv="Content-Type" content="text/html charset=windows-1252"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;">Julien,<div><br></div><div>The flame retention disk is BELOW the secondary air. The Flame retention disk and the thee deflectors form what might be called a virtual combustion chamber. One question is what is the best vertical distance between the flame retention disk and the three deflectors: i.e. what is the best depth of the combustion zone?</div><div><br></div><div>I agree about the engineering. It maybe that Dartmouth’s Thayer School will do some work in this domain. I am working with their Humanitarian Engineering group based at the Thayer School of Engineering.</div><div><br></div><div>Cheers,</div><div><br></div><div>Jock<br><div>
<div style="color: rgb(0, 0, 0); font-family: Arial; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: -webkit-auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;">Jock Gill<br>P.O. Box 3<br>Peacham, VT 05862<br><br>+1 (802) 503-1258</div><div style="color: rgb(0, 0, 0); font-family: Arial; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: -webkit-auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;"><br></div><div style="color: rgb(0, 0, 0); font-family: Arial; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: -webkit-auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;">Stewardship, not dominion<br><br></div>
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<br><div><div>On May 26, 2014, at 10:48 AM, Julien Winter <<a href="mailto:winter.julien@gmail.com">winter.julien@gmail.com</a>> wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite"><div dir="ltr"><div class="gmail_extra"><div class="gmail_quote"><div>Hi Jock;</div><div><br></div><div>Thanks for the photographs and detailed description of your stove. It is interesting to see what you are achieving with the "flame turbulence" hypothesis using your deflector disks. </div>
<div><br></div><div>Is your central flame retention disk above or below the secondary air inlet? If it is above the secondary air, have you included your flame buffer cylinder and paraphernalia?</div><div><br></div><div>
Once developers like us have some promising prototypes, it will be good if the investigation is taken-up by a well equipped laboratory, because there are important variables that we are not equipped to measure. In particular, the superficial velocity of primary air, velocity of exhaust gases with concentration of CO and particulate emissions. Reaction temperatures would be useful as well. The properties of our burners need to be measured on a variety of fuels, and over a range of superficial velocities.</div>
<div><br></div><div>At the moment, we are frustrated by being able to make only qualitative judgments. But the good thing is that the qualitative observations are pointing in the right direction for someone to developed a research proposal to get some solid funding. Except for the recent article by Birzer et al., 2013 in the Journal of Humanitarian Engineering, there are no peer-reviewed articles on the science of natural draft TLUDs. </div>
<div><br></div><div><br></div><div>Cheers,</div><div>Julien.</div><div><br></div></div><br clear="all"><br>-- <br><div dir="ltr">Julien Winter<br>Cobourg, ON, CANADA<br></div>
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