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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 Jock<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'>There is another item that should be on your list in order to get the desired result:<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><div><p class=MsoNormal>My hope for the combustion chamber concept is that it will:<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>1. Increase residence time;<o:p></o:p></p></div><div><p class=MsoNormal>2. Increase turbulence/mixing;<o:p></o:p></p></div><div><p class=MsoNormal>3. Yield a hotter gas;<o:p></o:p></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>4. Optimise the excess air level<o:p></o:p></span></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>All of this will be helpful in minimizing creosote and soot. A hot enough combustion chamber will ‘crack’ and burn the tars that would otherwise form creosote.<o:p></o:p></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><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>It is true that ‘hot enough’ is achieved by limiting the chilling effect of unnecessary air. The purpose of mixing it to be able to reduce that air requirement. The residence time is for the same reason. The hotter gas is the result – it has as little as possible useless nitrogen in it, drawn in with the needed oxygen.<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Because of the critical important of this EA factor, and because it has to be measured at the point where the gases exit the burner (usually at the edge of the pot) one has to use a device which keeps out ambient air. It is why it is not possible to develop a stove under a hood, because you cannot tell with a hood what the EA level is, and it is critical to the combustor development process.<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><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>For many TLUD’s the issue is not excessive amounts of air, it is from too little, applied to the combustion too late in the gas column. This causes characteristic effects: flames emerging around the whole pot and a lot of smoke. TLUD’s are not magically clean-burning, but they can be in the right conditions.<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><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Regards<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Crispin<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></div></div></body></html>