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</o:shapelayout></xml><![endif]--></head><body lang=FR link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:9.0pt;font-family:"Verdana","sans-serif"'>Dear users<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:9.0pt;font-family:"Verdana","sans-serif"'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:9.0pt;font-family:"Verdana","sans-serif"'>I try to understand the discrepancy of UWin variations between an horizontal window (slope=0 in Window Type Manager, blue line in attached chart) and a vertical one (slope=90 in Window Type Manager, pink line in attached chart).<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:9.0pt;font-family:"Verdana","sans-serif"'>I guess that it is mainly due to the convective heat exchange coefficient between the individual glazings. As specified in §5.4.2.4 of user manual, the convective transfer is indeed calculated from the surface temperature difference (red line in attached chart) and the slope of the window.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:9.0pt;font-family:"Verdana","sans-serif"'>My questions now.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:9.0pt;font-family:"Verdana","sans-serif"'>1/ Could anyone confirm that my guess is actually correct?<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:9.0pt;font-family:"Verdana","sans-serif"'>2/ What about the Nu computation in case of cos(Beta)=0 in Eq. 5.4.2-13?<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:9.0pt;font-family:"Verdana","sans-serif"'>3/ Uw values of manufactured windows should be quite different depending on their intended orientation. Are the Uw values of roof windows specified with increased convection effects?<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:9.0pt;font-family:"Verdana","sans-serif"'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:9.0pt;font-family:"Verdana","sans-serif"'>Thanks a lot for your help on that !<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:9.0pt;font-family:"Verdana","sans-serif";color:#404040'>--<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:9.0pt;font-family:"Verdana","sans-serif";color:#404040'>Antoine Gautier<br>Solam</span><span style='font-size:9.0pt;font-family:"Verdana","sans-serif";color:#70B221'>en</span><span style='font-size:9.0pt;font-family:"Verdana","sans-serif";color:#404040'> SAS</span><span style='font-size:9.0pt;font-family:"Verdana","sans-serif";color:black'><br></span><span style='font-size:9.0pt;font-family:"Verdana","sans-serif";color:#404040'>+33 6 58 24 02 60<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:9.0pt;font-family:"Verdana","sans-serif";color:#404040'>antoine.gautier@solamen.fr</span><span style='font-size:9.0pt;font-family:"Verdana","sans-serif";color:black'><o:p></o:p></span></p><p class=MsoNormal><o:p> </o:p></p></div></body></html>