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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'>Alex, Julien and all<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 quite a bit of data collected during tests of ND-TLUD’s in Mongolia – maybe 300 tests – that one can look over to see when the idea conditions exist for optimised burning.<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'>Certain ‘truths’ emerge relating to the excess air level, the secondary provision and its placement, the ignition time and so on.<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'>What is missing is a clear description of the architecture for each stove. However it is not without its usefulness. By using the date (which is all real-time) we have been able to make suggestions to the producers that has resulted in a consistent set of ND stoves with >90-99% reduction in CO and PM emissions. <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'>No one has yet really applied all the lessons – they just build and test and if good enough, that is good enough. There has not been (yet) an optimisation process. <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'>We should expect that some of the ‘rules’ of stove building are perhaps thought experiments more than rules. Every now and then someone comes with a very different approach (Alex E consistently being one of those people) to combustion that seems to be contrary to ‘rules of experience’. <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'>I hear from Aprovecho’s stove camp this week that Adrian Padt’s stove did very well in the testing and it is certainly in the category of stoves that ‘don’t follow the rules’ (which always intrigues me).<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'>That stove has been tested in two different labs at different altitudes using two different fuels and different burn cycles and it performs extremely well. It seems that experience has been repeated again at Aprovecho. Congrats to Adrian for a high performance all metal stove. <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><b><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p> </o:p></span></b></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><div><p class=MsoNormal>Julien,<o:p></o:p></p><div><p class=MsoNormal>Agreed. Its been a twenty year wait for basic in depth research on natural draft TLUDs.<o:p></o:p></p></div><div><p class=MsoNormal>Natural draft mixing was my passion for a while. I think "natural draft" is still too broad a term. There is a dramatic difference in gas mixing potential of 30, 90 cm of buoyancy. <o:p></o:p></p></div><div><p class=MsoNormal>It will be interesting to see the results shared, but I am inclined to think the money would be better spent putting portable combustion gas analysers in the hands of folks like you and Harris. <o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>My excess air for today,<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Alex<o:p></o:p></p></div></div><div><p class=MsoNormal><o:p> </o:p></p></div></div></body></html>