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</o:shapelayout></xml><![endif]--></head><body bgcolor=white 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 Kevin<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 is indeed a refuelling. The initial drop is the coal burning. Then it is refuelled (jump up in mass) then it burns down again and eventually goes out completely after some hours. <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 surprises are the shaking of the stove scale by the wind in the night, and then the increase in the system mass. The curve moves up and down in a manner surprisingly similar to the mass change charts of Battacharyya. This was a traditional stove and the burning of coal near the edges of the chamber is not all perfect. How much O2 can char pick up in a few hours? Is this real or an artifact of the wind?<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><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><o:p> </o:p></p><div><p class=MsoNormal><span style='font-family:"Arial","sans-serif";color:windowtext'>Dear Crispin</span><span style='color:windowtext'><o:p></o:p></span></p></div><div><p class=MsoNormal><span style='color:windowtext'> <o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-family:"Arial","sans-serif";color:windowtext'>I don't understand the graph...</span><span style='color:windowtext'><o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-family:"Arial","sans-serif";color:windowtext'>1: What are the units of the vertical scale? (Is it Grams weight?)</span><span style='color:windowtext'><o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-family:"Arial","sans-serif";color:windowtext'>2: The weight (?) gain is virtually instantaneous.</span><span style='color:windowtext'><o:p></o:p></span></p></div><div><p class=MsoNormal><span style='color:windowtext'> <o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-family:"Arial","sans-serif";color:windowtext'>Presuming the vertical axis is the weight of the stove system and contents in grams, the instantaneous system weight gain would be 108,400 less 103,800 = 4,600 grams.</span><span style='color:windowtext'><o:p></o:p></span></p></div><div><p class=MsoNormal><span style='color:windowtext'> <o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-family:"Arial","sans-serif";color:windowtext'>What could possibly explain such a large and instantaneous weight gain? Did someone simply put more wood or coal on the fire?</span><span style='color:windowtext'><o:p></o:p></span></p></div><div><p class=MsoNormal><span style='color:windowtext'> <o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-family:"Arial","sans-serif";color:windowtext'>Best wishes,</span><span style='color:windowtext'><o:p></o:p></span></p></div><div><p class=MsoNormal><span style='color:windowtext'> <o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-family:"Arial","sans-serif";color:windowtext'>Kevin</span><span style='color:windowtext'><o:p></o:p></span></p></div><blockquote style='border:none;border-left:solid black 1.5pt;padding:0mm 0mm 0mm 4.0pt;margin-left:3.75pt;margin-top:5.0pt;margin-right:0mm;margin-bottom:5.0pt'><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:windowtext'>----- Original Message ----- <o:p></o:p></span></p></div><div><p class=MsoNormal style='background:#E4E4E4'><b><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:windowtext'>From:</span></b><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:windowtext'> <a href="mailto:crispinpigott@gmail.com" title="crispinpigott@gmail.com">Crispin Pemberton-Pigott</a> <o:p></o:p></span></p></div><div><p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:windowtext'>To:</span></b><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:windowtext'> <a href="mailto:stoves@lists.bioenergylists.org" title="stoves@lists.bioenergylists.org">'Discussion of biomass cooking stoves'</a> <o:p></o:p></span></p></div><div><p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:windowtext'>Sent:</span></b><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:windowtext'> Monday, February 25, 2013 2:45 PM<o:p></o:p></span></p></div><div><p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:windowtext'>Subject:</span></b><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:windowtext'> Re: [Stoves] combustion of char -- spontaneous and dangerous<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='color:windowtext'><o:p> </o:p></span></p></div><pre><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Dear Friends<o:p></o:p></span></pre><pre><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></pre><pre><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Here is a mass profile, raw and smoothed with 21 point simple averaging (minus 1000 to pull it down so you can see it).<o:p></o:p></span></pre><pre><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></pre></blockquote></div></body></html>