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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'>Dear Frank<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'>Paint a small circle about 40mm in diameter black. But don’t paint the rest. The circle will give you some idea of the temperature of the rest of the stove, but if you paint the whole thing it will shed heat much more effectively and cool considerably.<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'>Your IR thermometer should also have a contact tip – a thermocouple on a wire that plugs into it. Put the tip on the hot surface to get a reading. By comparing it with the IR reading, you can calculate a correction factor. That can be used to calculate the emissivity value (if you want it).<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><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><b><span lang=EN-US style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span lang=EN-US style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> Stoves [mailto:stoves-bounces@lists.bioenergylists.org] <b>On Behalf Of </b>Steve Taylor<br><b>Sent:</b> Saturday, January 12, 2013 6:21 AM<br><b>To:</b> Discussion of biomass cooking stoves<br><b>Subject:</b> Re: [Stoves] Measuring temperature<o:p></o:p></span></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;margin-bottom:12.0pt'><o:p> </o:p></p><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>On 12 January 2013 00:21, Frank Shields <<a href="mailto:frank@compostlab.com" target="_blank">frank@compostlab.com</a>> wrote:<o:p></o:p></p><div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US style='color:#1F497D'>Stovers,</span><span lang=EN-US><o:p></o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US style='color:#1F497D'> </span><span lang=EN-US><o:p></o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US style='color:#1F497D'>I was running an experiment using shinny stove pipe as a ‘stove’ and using the IR detector was measuring the temperature on the outside of the pipe. It read about 30c. But was much higher as noted when I tried to hold the pipe. Is this inaccuracy due to the reflective surface?</span><span lang=EN-US><o:p></o:p></span></p></div></div><div><p class=MsoNormal><br>Hi Frank, <br>Yes, you've run into the issue of emissivity of the pipe - black emits better than shiny. <br><br>Steve <o:p></o:p></p></div></div></div></body></html>