<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> <HTML><HEAD> <META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=iso-8859-1"> <META content="MSHTML 6.00.5730.11" name=GENERATOR></HEAD> <BODY style="WORD-WRAP: break-word; -khtml-nbsp-mode: space; -khtml-line-break: after-white-space"> <DIV dir=ltr align=left> <DIV><FONT face=Arial color=#0000ff size=2><SPAN class=365405415-29112006>Hello Jon,</SPAN></FONT></DIV> <DIV><FONT face=Arial color=#0000ff size=2><SPAN class=365405415-29112006></SPAN></FONT> </DIV> <DIV><SPAN class=365405415-29112006><FONT face=Arial><FONT color=#0000ff><FONT size=2>the unit is "one/hour"<SPAN class=376580807-30112006> = ach</SPAN></FONT></FONT></FONT></SPAN></DIV> <DIV><FONT face=Arial color=#0000ff size=2><SPAN class=365405415-29112006></SPAN></FONT> </DIV> <DIV><FONT face=Arial color=#0000ff size=2><SPAN class=365405415-29112006>You are right, with<SPAN class=376580807-30112006> a</SPAN> liter per hour it would be a very small air change rate. I'm sorry, <SPAN class=376580807-30112006>that it </SPAN>was not clear.</SPAN></FONT></DIV> <DIV><FONT face=Arial color=#0000ff size=2><SPAN class=365405415-29112006></SPAN></FONT> </DIV> <DIV><FONT face=Arial color=#0000ff size=2><SPAN class=365405415-29112006>Regards</SPAN></FONT></DIV> <DIV><FONT face=Arial color=#0000ff size=2><SPAN class=365405415-29112006>Monika</SPAN></FONT></DIV> <DIV><FONT face=Arial color=#0000ff size=2></FONT> </DIV></DIV><BR> <DIV class=OutlookMessageHeader lang=en-us dir=ltr align=left> <HR tabIndex=-1> <FONT face=Tahoma size=2><B>From:</B> Jon Hand (clcv10) [mailto:jon@esru.strath.ac.uk] <BR><B>Sent:</B> Wednesday, November 29, 2006 4:52 PM<BR><B>To:</B> Hall Monika<BR><B>Cc:</B> esp-r@lists.strath.ac.uk<BR><B>Subject:</B> Re: [esp-r] air flow rate in air flow net<BR></FONT><BR></DIV> <DIV></DIV> <BLOCKQUOTE type="cite"> <DIV style="MARGIN: 0px"><FONT class=Apple-style-span face="Times New Roman">I have a constant air flow rate of 1.0 1/h for working days (7:00-18:00). All other times the air flow rate is constant 0.5 1/h.</FONT><FONT class=Apple-style-span face="Times New Roman"> </FONT></DIV></BLOCKQUOTE><BR> <DIV>This caught my attention - one litre per hour is a really really small number in</DIV> <DIV>terms of air flow for any zone bigger than the box an ipod came in.  This would</DIV> <DIV>be held as an equivalent m^3/s which is at the 4th decimal place and</DIV> <DIV>the 0.5 litre per hour might be at the 5th decimal place so it might</DIV> <DIV>be possible that simple rounding errors and numerical noise are factors.</DIV> <DIV><BR class=khtml-block-placeholder></DIV> <DIV>And a change in volume in a zone could easily result in a bigger</DIV> <DIV>flow than this fixed rate.  Suggest a run with 10 litres per hour etc.</DIV> <DIV>to see if the glitch goes away.</DIV> <DIV><BR class=khtml-block-placeholder></DIV> <DIV>-ESRU</DIV></BODY></HTML>