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</o:shapelayout></xml><![endif]--></head><body lang=EN-CA link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'>Dear Martin<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'>Here is the technique. It was used as a way to operate a cross draft fire in a bottom-lit updraft stove. The fuel is always piled to the same depth. For different fire-powers, the width of the channel is changed, not the fuel depth. The operating time is always about the same.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'>This technique - End-Lit Cross Draft (ELCD) is being copied around the country here and there without no one pushing it at all. I heard that in January. It reduces emissions about 80%, a little more, without replacing the stove. It involves the insertion of a flame tube into the end wall, 60-70mm diameter. That costs about $1.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'>The fuel saving is perhaps 10-20%. It runs far smoother – no big peaks of heating and followed by fire collapse.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'>Regards<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'>Crispin<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><img width=189 height=203 id="Picture_x0020_1" src="cid:image003.jpg@01D0F06D.D5AFBCB0"><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'>.The big space can be narrowed temporarily.<o:p></o:p></span></p><p class=MsoNormal><img width=189 height=194 id="Picture_x0020_2" src="cid:image004.jpg@01D0F06D.D5AFBCB0"><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'>Here the space is only 110mm wide.<o:p></o:p></span></p><p class=MsoNormal><img width=189 height=142 id="Picture_x0020_3" src="cid:image005.jpg@01D0F06D.D5AFBCB0"><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'>The space is filled with fuel.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'>The wood is in a hole so air can come up through the grate below.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'>The flame tube is visible on the left. It is made from sheet metal and set in clay.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'>After the metal burns away the clay hole will remain.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'>All smoke and flames have to pass through the hole so there is an active fire inside the tube leading to the heat exchanger.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal>Kirk,<o:p></o:p></p><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>first of all, your stoves and thoughts about TLUD's are very interesting. And in my opinion<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal> the venturi-concept, you are talking about, -how ever managed- will be generally the next important step for better burning; - and for less blacked pots!!! <o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>A presumption I made a year or two ago: <o:p></o:p></p></div><div><p class=MsoNormal>The (nominal-) power rate of a good working stove has a more or less narrow relation to the grate-surface, and/or the burning-chamber-volume.<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal> I calculated the given numbers of some different commercial stoves. My calculations confirmed my guess.<o:p></o:p></p></div><div><p class=MsoNormal>I dont remember the numbers, but it is easy to calculate the numbers out of available commercial data.<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Additional I remind to Crispin's postings, some time ago:<o:p></o:p></p></div><div><p class=MsoNormal>He reported, that he made the burning-chamber of some coal stoves in Ulanbaator smaller, by just filling some space of the burning-chamber-space with bricks. And some surface of the grate. In combination with special incending-procedure, that gave better burning; even by transforming the may of stoves there, there was an enormous reduction (more than 90%) of air-pollution. <o:p></o:p></p></div><div><p class=MsoNormal>So I suspect, if you would use the right-balanced amount of burning-chamber-volume, you could get a step forward. The volume within the venturi-riser-burner-tube should be included in the calculation; but in the tube there will be, -hopefully- a burning some similar to a LPG or NG flame, which will afford less volume. <o:p></o:p></p></div><div><p class=MsoNormal>You could take the power-rate which you achieve with low emission, for extrapolating the stove dimensions for your desired 5 kW output.<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Regards<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Martin<o:p></o:p></p></div></div></body></html>