<html><head><style type="text/css"><!-- DIV {margin:0px;} --></style></head><body><div style="font-family:tahoma, new york, times, serif;font-size:10pt"><DIV>I put my comments in blue below.</DIV>
<DIV> </DIV>
<DIV> </DIV>
<DIV>
<DIV>Ding Li, PhD, PE<BR></DIV>
<DIV style="FONT-SIZE: 10pt; FONT-FAMILY: tahoma, new york, times, serif">Capital Engineering Consultants Inc.<BR><SPAN class=yshortcuts id=lw_1243988966_1 style="BACKGROUND: none transparent scroll repeat 0% 0%; CURSOR: hand; BORDER-BOTTOM: #0066cc 1px dashed">11020 Sun Center Drive, Suite 100<BR>Rancho Cordova, CA 95670</SPAN></DIV>
<DIV style="FONT-SIZE: 10pt; FONT-FAMILY: tahoma, new york, times, serif">Tel: <SPAN class=yshortcuts id=lw_1243988966_2 style="BACKGROUND: none transparent scroll repeat 0% 0%; CURSOR: hand; BORDER-BOTTOM: #0066cc 1px dashed">916-851-3579</SPAN><BR>Fax: <SPAN class=yshortcuts id=lw_1243988966_3 style="BACKGROUND: none transparent scroll repeat 0% 0%; CURSOR: hand; BORDER-BOTTOM: #0066cc 1px dashed">916-631-4424</SPAN><BR></DIV></DIV>
<DIV style="FONT-SIZE: 10pt; FONT-FAMILY: tahoma, new york, times, serif"><BR>
<DIV style="FONT-SIZE: 12pt; FONT-FAMILY: times new roman, new york, times, serif"><FONT face=Tahoma size=2>
<HR SIZE=1>
<B><SPAN style="FONT-WEIGHT: bold">From:</SPAN></B> Frederik Vildbrad Winther (FRW) <FRW@ramboll.dk><BR><B><SPAN style="FONT-WEIGHT: bold">To:</SPAN></B> Paul Carey <paul@zed-uk.com>; bldg-sim@lists.onebuilding.org<BR><B><SPAN style="FONT-WEIGHT: bold">Sent:</SPAN></B> Tuesday, June 2, 2009 6:35:38 AM<BR><B><SPAN style="FONT-WEIGHT: bold">Subject:</SPAN></B> Re: [Bldg-sim] Links between CFD or MZ and thermal simulations for simulating air and temperature distributions in atria<BR></FONT><BR>
<STYLE> _filtered {
font-family:Cambria Math;}
_filtered {
font-family:Calibri;}
_filtered {
font-family:Tahoma;}
_filtered {
font-family:Verdana;}
_filtered {
font-family:MS Reference Sans Serif;}
_filtered {margin:72.0pt 72.0pt 72.0pt 72.0pt;}
P.MsoNormal {
FONT-SIZE:12pt;MARGIN:0cm 0cm 0pt;FONT-FAMILY:"Times New Roman", "serif";}
LI.MsoNormal {
FONT-SIZE:12pt;MARGIN:0cm 0cm 0pt;FONT-FAMILY:"Times New Roman", "serif";}
DIV.MsoNormal {
FONT-SIZE:12pt;MARGIN:0cm 0cm 0pt;FONT-FAMILY:"Times New Roman", "serif";}
A:link {
COLOR:blue;TEXT-DECORATION:underline;}
SPAN.MsoHyperlink {
COLOR:blue;TEXT-DECORATION:underline;}
A:visited {
COLOR:purple;TEXT-DECORATION:underline;}
SPAN.MsoHyperlinkFollowed {
COLOR:purple;TEXT-DECORATION:underline;}
P {
FONT-SIZE:12pt;MARGIN-LEFT:0cm;MARGIN-RIGHT:0cm;FONT-FAMILY:"Times New Roman", "serif";}
P.MsoAcetate {
FONT-SIZE:8pt;MARGIN:0cm 0cm 0pt;FONT-FAMILY:"Tahoma", "sans-serif";}
LI.MsoAcetate {
FONT-SIZE:8pt;MARGIN:0cm 0cm 0pt;FONT-FAMILY:"Tahoma", "sans-serif";}
DIV.MsoAcetate {
FONT-SIZE:8pt;MARGIN:0cm 0cm 0pt;FONT-FAMILY:"Tahoma", "sans-serif";}
SPAN.EmailStyle18 {
COLOR:#1f497d;FONT-FAMILY:"Calibri", "sans-serif";}
SPAN.BalloonTextChar {
FONT-FAMILY:"Tahoma", "sans-serif";}
.MsoChpDefault {
FONT-SIZE:10pt;}
DIV.Section1 {
}
</STYLE>
<DIV dir=ltr align=left><SPAN class=683285912-02062009><FONT face=Verdana size=2>Hi Paul,</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=683285912-02062009><FONT face=Verdana size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=683285912-02062009><FONT face=Verdana size=2>Thanks for your reply. I haven't heard about DesignBuilder CFD before and I have only heard and peaked to EnergyPlus. EnergyPlus seems OK for simulating multizones and thermal simulations. Do you know how it handles stratification? I am thinking of using thermal simulations, with a good link to a multizone program so that the 2 programs can predict the air movement as well as the stratification in the room. I am then thinking of doing 4 CFD studies and these simulations should have input from the thermal simulation. The output from the CFD simulations should then be compared to the results from the thermal simulation. The two calculations should therefor be reasonably comparable (in the end).</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=683285912-02062009><FONT face=Verdana size=2></FONT></SPAN><FONT color=#0000ff></FONT> </DIV>
<DIV dir=ltr align=left><FONT color=#0000ff>DesignBuilder just released v2. I'm not quite familiar with its CFD module, but I believe DB was mainly used with E+. If you want to achieve stratification, you have to use some CFD package. E+ has a DV module which may have stratification feature, but that's only for DV. </FONT></DIV>
<DIV dir=ltr align=left><FONT color=#0000ff></FONT> </DIV>
<DIV dir=ltr align=left><SPAN class=683285912-02062009><FONT face=Verdana size=2>I think that the use LES turbulence model for indoor climate analysis is rather hazardous because this turbulence model is mostly used for fire and smoke simulations. I have obtained good results for indoor climate using ke-turbulence model. Is my thought "out of date" on this point? Does ke-turbulence model also work for larger rooms? When can/should LES-turbulence model be used, apart from smoke/fire simulations? The problem is also getting a thermal simulation program, which can import the results from a CFD calculation. </FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=683285912-02062009><FONT face=Verdana size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=683285912-02062009><FONT face=Verdana size=2>Using the transient calculations could prove very useful in showing the uncertainty in the CFD calculations. However, can I, when importing the boundary conditions from the thermal simulation to the CFD simulation, import the temperature stratefication as a start condition for the simulation? What is your experience on coupling thermal/multizone simulations with CFD calculations? Does it work? It could be very useful if the CFD calculation starts with the same boundary conditions and results from the thermal simulation, rather than starting from scratch every time a CFD analysis has to be performed.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=683285912-02062009><FONT face=Verdana size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><FONT color=#0000ff>I'm not sure the exact meaning of your "thermal simulation". If you refer to the mechanical load calculation software, eg. Trane trace or other heating/cooling software, the answer is yes. You can calculate the heat flux at the exterior wall/roof/floor and then import them into your CFD model. But you need to verify the CFD result carefully since the setpoint may be different from the result of your CFD modeling. This could cause some inaccurate result.</FONT></DIV>
<DIV dir=ltr align=left><FONT color=#0000ff></FONT> </DIV>
<DIV dir=ltr align=left><SPAN class=683285912-02062009><FONT face=Verdana size=2>Do you know of any papers dealing with modeling of solar gain in CFD tools?</FONT></SPAN></DIV>
<DIV> </DIV>
<DIV><FONT color=#0000ff></FONT> </DIV>
<DIV> </DIV>
<DIV class=Section1>
<DIV><SPAN style="FONT-WEIGHT: normal; FONT-SIZE: 8pt; COLOR: #000000; LINE-HEIGHT: 11pt; FONT-FAMILY: Verdana; TEXT-DECORATION: none"><SPAN> </SPAN></DIV>
<DIV><SPAN style="FONT-WEIGHT: normal; FONT-SIZE: 8pt; COLOR: #000000; LINE-HEIGHT: 11pt; FONT-FAMILY: Verdana; TEXT-DECORATION: none"><SPAN>Med venlig hilsen</SPAN></DIV>
<DIV><SPAN style="FONT-WEIGHT: bold; FONT-SIZE: 9pt; COLOR: #000000; LINE-HEIGHT: 11pt; FONT-FAMILY: Verdana; TEXT-DECORATION: none"><SPAN>Frederik V. Winther</SPAN></DIV>
<DIV><SPAN style="FONT-WEIGHT: normal; FONT-SIZE: 8pt; COLOR: #000000; LINE-HEIGHT: 11pt; FONT-FAMILY: Verdana; TEXT-DECORATION: none"><SPAN> </SPAN></DIV>
<DIV><SPAN style="FONT-WEIGHT: normal; FONT-SIZE: 8pt; COLOR: #000000; LINE-HEIGHT: 11pt; FONT-FAMILY: Verdana; TEXT-DECORATION: none"><SPAN>Civilingeniør, Indeklima og Energi</SPAN></DIV>
<DIV><SPAN style="FONT-WEIGHT: normal; FONT-SIZE: 8pt; COLOR: #000000; LINE-HEIGHT: 11pt; FONT-FAMILY: Verdana; TEXT-DECORATION: none"><SPAN>Ingeniør</SPAN></DIV>
<DIV><SPAN style="FONT-WEIGHT: normal; FONT-SIZE: 8pt; COLOR: #000000; LINE-HEIGHT: 11pt; FONT-FAMILY: Verdana; TEXT-DECORATION: none"><SPAN>Indeklima og Miljø</SPAN></DIV>
<DIV><SPAN style="FONT-WEIGHT: normal; FONT-SIZE: 8pt; COLOR: #000000; LINE-HEIGHT: 11pt; FONT-FAMILY: Verdana; TEXT-DECORATION: none"><SPAN> </SPAN></DIV>
<DIV><SPAN style="FONT-WEIGHT: normal; FONT-SIZE: 8pt; COLOR: #000000; LINE-HEIGHT: 11pt; FONT-FAMILY: Verdana; TEXT-DECORATION: none"><SPAN>D +45 4598 6254</SPAN></DIV>
<DIV><SPAN style="FONT-WEIGHT: normal; FONT-SIZE: 8pt; COLOR: #000000; LINE-HEIGHT: 11pt; FONT-FAMILY: Verdana; TEXT-DECORATION: none"><SPAN style="FONT-WEIGHT: normal; FONT-SIZE: 8pt; COLOR: #009ee3; FONT-FAMILY: Verdana; TEXT-DECORATION: none"><SPAN><A title=FRW@RAMBOLL.DK href="mailto:frw@ramboll.dk" target=_blank rel=nofollow ymailto="mailto:frw@ramboll.dk"><SPAN style="COLOR: #009ee3; TEXT-DECORATION: none">frw@ramboll.dk</SPAN></A></SPAN></SPAN></DIV>
<DIV><SPAN style="FONT-WEIGHT: normal; FONT-SIZE: 8pt; COLOR: #000000; LINE-HEIGHT: 11pt; FONT-FAMILY: Verdana; TEXT-DECORATION: none"><SPAN style="FONT-WEIGHT: normal; FONT-SIZE: 8pt; COLOR: #000000; FONT-FAMILY: Times New Roman; TEXT-DECORATION: none"><SPAN>________________________________________</SPAN></SPAN></DIV>
<DIV><SPAN style="FONT-WEIGHT: normal; FONT-SIZE: 8pt; COLOR: #000000; LINE-HEIGHT: 11pt; FONT-FAMILY: Verdana; TEXT-DECORATION: none"><SPAN> </SPAN></DIV>
<DIV><SPAN style="FONT-WEIGHT: normal; FONT-SIZE: 8pt; COLOR: #000000; LINE-HEIGHT: 11pt; FONT-FAMILY: Verdana; TEXT-DECORATION: none"><SPAN>Rambøll</SPAN></DIV>
<DIV><SPAN style="FONT-WEIGHT: normal; FONT-SIZE: 8pt; COLOR: #000000; LINE-HEIGHT: 11pt; FONT-FAMILY: Verdana; TEXT-DECORATION: none"><SPAN>Teknikerbyen 31</SPAN></DIV>
<DIV><SPAN style="FONT-WEIGHT: normal; FONT-SIZE: 8pt; COLOR: #000000; LINE-HEIGHT: 11pt; FONT-FAMILY: Verdana; TEXT-DECORATION: none"><SPAN>DK-2830 Virum</SPAN><SPAN style="FONT-WEIGHT: normal; FONT-SIZE: 8pt; COLOR: #000000; FONT-FAMILY: Times New Roman; TEXT-DECORATION: none"><SPAN></SPAN></SPAN></DIV>
<DIV><SPAN style="FONT-WEIGHT: normal; FONT-SIZE: 8pt; COLOR: #000000; LINE-HEIGHT: 11pt; FONT-FAMILY: Verdana; TEXT-DECORATION: none"><SPAN style="FONT-WEIGHT: normal; FONT-SIZE: 8pt; COLOR: #009ee3; FONT-FAMILY: Verdana; TEXT-DECORATION: none"><SPAN><A title=WWW.RAMBOLL.DK href="http://www.ramboll.dk/" target=_blank rel=nofollow><SPAN style="COLOR: #009ee3; TEXT-DECORATION: none">www.ramboll.dk</SPAN></A></SPAN></SPAN></DIV>
<DIV class=MsoNormal> </DIV></DIV></SPAN></SPAN></SPAN></SPAN></SPAN></SPAN></SPAN></SPAN></SPAN></SPAN></SPAN></SPAN></SPAN></SPAN></SPAN></SPAN>
<DIV> </DIV><BR>
<DIV class=OutlookMessageHeader lang=en-us dir=ltr align=left>
<HR tabIndex=-1>
<FONT face=Tahoma size=2><B>From:</B> Paul Carey [mailto:paul@zed-uk.com] <BR><B>Sent:</B> 29. maj 2009 16:49<BR><B>To:</B> Frederik Vildbrad Winther (FRW); bldg-sim@lists.onebuilding.org<BR><B>Subject:</B> RE: [Bldg-sim] Links between CFD or MZ and thermal simulations for simulating air and temperature distributions in atria<BR></FONT><BR></DIV>
<DIV></DIV>
<DIV class=Section1>
<P class=MsoNormal><SPAN style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'">Hi Frederik,</SPAN></P>
<P class=MsoNormal><SPAN style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'"> </SPAN></P>
<P class=MsoNormal><SPAN style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'">DesignBuilder CFD would allow you to come up with an EnergyPlus multizone air flow linked thermal simulation coupled with a steady state CFD solution. This has recently been released and is a cost-effective way of linking the 2. If you used DesignBuilder to develop the energy model/Steady State CFD solution carried out and then use their model export options to give you the model upon which to then import it into a more complex transient CFD tool should it be necessary. To some extent you could argue whether or not you need the transient analysis as the dynamic simulations should give you the temporal solution for the airflow and then you could look at what happens for say peak or mean flow conditions perhaps. But I’d suggest that it might well be worth it from what you are describing as even a well set up thermal multizone
model would do most of what you describe, but the thermal stratification issues are going to be a sticking point for most simulation tools, both Dynamic or CFD to some extent.</SPAN></P>
<P class=MsoNormal><SPAN style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'"> </SPAN></P>
<P class=MsoNormal><SPAN style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'">If you really wanted to see the time effects of the Solar Gain on airflows, etc, there are many CFD tools available that would be able to do this, obviously all the major CFD engines would do this comfortably (Airpak from Ansys Fluent most easily I suspect with its integrated solar gain modelling tool) but they are going to be quite expensive and there is quite a learning curve to some of them.</SPAN></P>
<P class=MsoNormal><SPAN style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'"> </SPAN></P>
<P class=MsoNormal><SPAN style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'">Alternatively, you could use something like PyroSim, which is a good front end for NIST that would probably be suitable. NIST does transient analysis and is used commonly for smoke/fire analysis. It uses LES turbulence models from memory and so would be likely to be more accurate for the sort of stratified flows you’d get in an Atria as well. You could then set transient boundaries based on files of data exported by the dynamic engine. Might take a bit of work, but it should work.</SPAN></P>
<P class=MsoNormal><SPAN style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'"> </SPAN></P>
<P class=MsoNormal><SPAN style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'">Regards</SPAN></P>
<P class=MsoNormal><SPAN style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'">Paul</SPAN></P>
<P class=MsoNormal><SPAN style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'"> </SPAN></P>
<P class=MsoNormal><SPAN style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'"> </SPAN></P>
<TABLE class=MsoTableGrid style="BORDER-RIGHT: medium none; BORDER-TOP: medium none; BORDER-LEFT: medium none; BORDER-BOTTOM: medium none; BORDER-COLLAPSE: collapse" cellSpacing=0 cellPadding=0 border=0>
<TBODY>
<TR>
<TD style="PADDING-RIGHT: 5.4pt; PADDING-LEFT: 5.4pt; PADDING-BOTTOM: 0cm; WIDTH: 162.3pt; PADDING-TOP: 0cm" vAlign=top width=216 rowSpan=2>
<P class=MsoNormal><SPAN style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'"><IMG id=Picture_x0020_1 height=154 width=142></SPAN></P></TD>
<TD style="PADDING-RIGHT: 5.4pt; PADDING-LEFT: 5.4pt; PADDING-BOTTOM: 0cm; WIDTH: 158.55pt; PADDING-TOP: 0cm" vAlign=top width=211>
<P class=MsoNormal><SPAN style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'">Dr Paul Carey</SPAN></P>
<P class=MsoNormal><SPAN style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'"> </SPAN></P>
<P class=MsoNormal><SPAN style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'">Director</SPAN></P>
<P class=MsoNormal><SPAN style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'">Low Carbon Energy Assessor</SPAN></P>
<P class=MsoNormal><SPAN style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'"> </SPAN></P></TD>
<TD style="PADDING-RIGHT: 5.4pt; PADDING-LEFT: 5.4pt; PADDING-BOTTOM: 0cm; WIDTH: 157.95pt; PADDING-TOP: 0cm" vAlign=top width=211>
<P class=MsoNormal><SPAN style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'">Zero Energy Design Ltd</SPAN></P>
<P class=MsoNormal><SPAN style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'">10A Portland Place</SPAN></P>
<P class=MsoNormal><SPAN style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'">2-22 Mottram Road</SPAN></P>
<P class=MsoNormal><SPAN style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'">Stalybridge</SPAN></P>
<P class=MsoNormal><SPAN style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'">SK15 3AD</SPAN></P>
<P class=MsoNormal><SPAN style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'"> </SPAN></P></TD></TR>
<TR>
<TD style="PADDING-RIGHT: 5.4pt; PADDING-LEFT: 5.4pt; PADDING-BOTTOM: 0cm; WIDTH: 158.55pt; PADDING-TOP: 0cm" vAlign=top width=211>
<P class=MsoNormal><SPAN style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'">T: 0161 3386200</SPAN></P>
<P class=MsoNormal><SPAN style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'">F: 0161 3031281</SPAN></P>
<P class=MsoNormal><SPAN style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'">M: 0789 4098012</SPAN></P></TD>
<TD style="PADDING-RIGHT: 5.4pt; PADDING-LEFT: 5.4pt; PADDING-BOTTOM: 0cm; WIDTH: 157.95pt; PADDING-TOP: 0cm" vAlign=top width=211>
<P class=MsoNormal><SPAN style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'">E: paul@zed-uk.com</SPAN></P>
<P class=MsoNormal><SPAN style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'">W: <A href="http://www.zed-uk.com/" target=_blank>www.zed-uk.com</A></SPAN></P>
<P class=MsoNormal><SPAN style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'"> </SPAN></P></TD></TR>
<TR>
<TD style="PADDING-RIGHT: 5.4pt; PADDING-LEFT: 5.4pt; PADDING-BOTTOM: 0cm; WIDTH: 162.3pt; PADDING-TOP: 0cm" vAlign=top width=216>
<P class=MsoNormal><SPAN style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'"> </SPAN></P>
<P class=MsoNormal><SPAN style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'"><IMG id=Picture_x0020_2 height=81 width=200></SPAN></P>
<P class=MsoNormal><SPAN style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'"> </SPAN></P></TD>
<TD style="PADDING-RIGHT: 5.4pt; PADDING-LEFT: 5.4pt; PADDING-BOTTOM: 0cm; WIDTH: 158.55pt; PADDING-TOP: 0cm" vAlign=top width=211>
<P class=MsoNormal><SPAN style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'"> </SPAN></P>
<P class=MsoNormal><SPAN style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'"> </SPAN></P>
<P class=MsoNormal><SPAN style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'"> </SPAN></P>
<P class=MsoNormal><SPAN style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'"> </SPAN></P></TD>
<TD style="PADDING-RIGHT: 5.4pt; PADDING-LEFT: 5.4pt; PADDING-BOTTOM: 0cm; WIDTH: 157.95pt; PADDING-TOP: 0cm" vAlign=top width=211>
<P class=MsoNormal><SPAN style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'"> </SPAN></P>
<P class=MsoNormal><SPAN style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'"> </SPAN></P></TD></TR>
<TR>
<TD style="PADDING-RIGHT: 5.4pt; PADDING-LEFT: 5.4pt; PADDING-BOTTOM: 0cm; WIDTH: 162.3pt; PADDING-TOP: 0cm" vAlign=top width=216>
<P class=MsoNormal><SPAN style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'"> </SPAN></P>
<P class=MsoNormal><SPAN style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'"><IMG id=Picture_x0020_3 height=88 width=110></SPAN></P>
<P class=MsoNormal><SPAN style="FONT-SIZE: 8pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'">Certificate No: GB16647</SPAN></P>
<P class=MsoNormal><SPAN style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'"> </SPAN></P></TD>
<TD style="PADDING-RIGHT: 5.4pt; PADDING-LEFT: 5.4pt; PADDING-BOTTOM: 0cm; WIDTH: 158.55pt; PADDING-TOP: 0cm" vAlign=top width=211>
<P class=MsoNormal><SPAN style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'"> </SPAN></P>
<P class=MsoNormal><SPAN style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'"><IMG id=Picture_x0020_4 height=88 width=110></SPAN></P>
<P class=MsoNormal><SPAN style="FONT-SIZE: 8pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'">Certificate No: GB16646</SPAN><SPAN style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'"></SPAN></P></TD>
<TD style="PADDING-RIGHT: 5.4pt; PADDING-LEFT: 5.4pt; PADDING-BOTTOM: 0cm; WIDTH: 157.95pt; PADDING-TOP: 0cm" vAlign=top width=211>
<P class=MsoNormal><SPAN style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'"> </SPAN></P></TD></TR></TBODY></TABLE>
<P class=MsoNormal><SPAN lang=EN-US style="FONT-SIZE: 9pt; COLOR: green; FONT-FAMILY: 'MS Reference Sans Serif', 'sans-serif'"> </SPAN></P>
<P class=MsoNormal><SPAN lang=EN-US style="FONT-SIZE: 9pt; COLOR: green; FONT-FAMILY: 'MS Reference Sans Serif', 'sans-serif'">Please carefully consider the environment before you print this email.</SPAN></P>
<P class=MsoNormal><SPAN lang=EN-US style="FONT-SIZE: 9pt; COLOR: green; FONT-FAMILY: 'MS Reference Sans Serif', 'sans-serif'"> </SPAN></P>
<P class=MsoNormal><SPAN lang=EN-US style="FONT-SIZE: 10pt; COLOR: #1f497d; FONT-FAMILY: 'Verdana', 'sans-serif'">Company Registered in England & Wales. Registration No. 5815068</SPAN></P>
<P class=MsoNormal><SPAN lang=EN-US style="FONT-SIZE: 10pt; COLOR: #1f497d; FONT-FAMILY: 'Verdana', 'sans-serif'">Registered Address: 10A Portland Place, 2-22 Mottram Road, Stalybridge, SK15 3AD, UK.</SPAN><SPAN lang=EN-US style="COLOR: #1f497d"></SPAN></P>
<P class=MsoNormal><SPAN lang=EN-US style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'"> </SPAN><SPAN lang=EN-US style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'"></SPAN></P>
<P class=MsoNormal><U><SPAN lang=EN-US style="FONT-SIZE: 10pt; COLOR: #1f497d; FONT-FAMILY: 'Verdana', 'sans-serif'">Privilege and Confidentiality Notice:</SPAN></U><U><SPAN lang=EN-US style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'"></SPAN></U></P>
<P class=MsoNormal style="MARGIN-RIGHT: 486pt"><SPAN lang=EN-US style="FONT-SIZE: 10pt; COLOR: #1f497d; FONT-FAMILY: 'Verdana', 'sans-serif'"> </SPAN></P>
<P class=MsoNormal><SPAN lang=EN-US style="FONT-SIZE: 10pt; COLOR: #1f497d; FONT-FAMILY: 'Verdana', 'sans-serif'">This email and any attachments to it are intended only for the party to whom they are addressed. They may contain privileged and/or confidential information. If you have received this transmission in error, please notify the sender immediately and delete any digital copies and destroy any paper copies. Thank you.</SPAN><SPAN lang=EN-US style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'"></SPAN></P>
<P class=MsoNormal><SPAN style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'"> </SPAN></P>
<P class=MsoNormal><SPAN style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'"> </SPAN></P>
<P class=MsoNormal><SPAN style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'"> </SPAN></P>
<P class=MsoNormal><SPAN style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'"> </SPAN></P>
<P class=MsoNormal><SPAN style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'"> </SPAN></P>
<P class=MsoNormal><SPAN style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'"> </SPAN></P>
<P class=MsoNormal><SPAN style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'"> </SPAN></P>
<P class=MsoNormal><SPAN style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'"> </SPAN></P>
<P class=MsoNormal><SPAN style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'"> </SPAN></P>
<P class=MsoNormal><SPAN style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'"> </SPAN></P>
<P class=MsoNormal><SPAN style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri', 'sans-serif'"> </SPAN></P>
<DIV>
<DIV style="BORDER-RIGHT: medium none; PADDING-RIGHT: 0cm; BORDER-TOP: #b5c4df 1pt solid; PADDING-LEFT: 0cm; PADDING-BOTTOM: 0cm; BORDER-LEFT: medium none; PADDING-TOP: 3pt; BORDER-BOTTOM: medium none">
<P class=MsoNormal><B><SPAN lang=EN-US style="FONT-SIZE: 10pt; FONT-FAMILY: 'Tahoma', 'sans-serif'">From:</SPAN></B><SPAN lang=EN-US style="FONT-SIZE: 10pt; FONT-FAMILY: 'Tahoma', 'sans-serif'"> bldg-sim-bounces@lists.onebuilding.org [mailto:bldg-sim-bounces@lists.onebuilding.org] <B>On Behalf Of </B>Frederik Vildbrad Winther (FRW)<BR><B>Sent:</B> 29 May 2009 13:17<BR><B>To:</B> bldg-sim@lists.onebuilding.org<BR><B>Subject:</B> [Bldg-sim] Links between CFD or MZ and thermal simulations for simulating air and temperature distributions in atria</SPAN></P></DIV></DIV>
<P class=MsoNormal> </P>
<P><SPAN lang=DA style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: 'Verdana', 'sans-serif'">Hi,</SPAN><SPAN lang=DA> </SPAN></P>
<P><SPAN lang=DA style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: 'Verdana', 'sans-serif'">I am currently starting up on simulating a relatively large atrium in Denmark (app. 55°N) with a glazed roof (sloped towards the sun - clever), open balconies with working areas connected to the atrium, as well as a smaller atrium with smaller openings connecting the two atria together with each other.<B> The main focus in the simulation is first of all the air velocity and temperature distribution in the occupied zone and on the balconies - describing the thermal comfort as well as draft rate.</B> The next focus is on integrating the smaller atria as a heat exchanger in winter time as well as analyzing if this can be used for cooling in summer time, transporting the air from outside to the biggest atrium, via the smaller atrium with little heating of the air. The calculations I want to perform in CFD also regards simulations of the solar gain in the biggest
atrium. However simulating radiation in CFD simulations require more computing power for bigger rooms with a lot of surfaces. Any advice on simulating solar gain in CFD? How can this dynamic gain be simulated in CFD? Another cool thing in this atrium would be the heat recovery of the extracted air in the top part of the atrium.</SPAN></P>
<P><SPAN lang=DA style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: 'Verdana', 'sans-serif'">Simulating this in a thermal simulation software requires a lot of luck to obtain the correct (and true) result in the first couple of simulations. However I am thinking of integrating the results from a CFD calculation into the thermal simulation. I am thinking of doing this as an iterative process, integrating the results from CFD when needed in the thermal simulations. This will probably result in at least 4 different simulations over a whole year, giving detailed results (temperature gradient, flow between zones, convective heat-transfer coefficients etc.) which can be used in the thermal simulation for these 4 periods over a year. As mentioned above simulating radiation in CFD is tough, I am thinking of leaving this calculation in the thermal simulation.</SPAN></P>
<P><SPAN lang=DA style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: 'Verdana', 'sans-serif'">Another simpler setup would be the integration of a multi-zone calculation in the thermal simulation giving a more coarse result of the main flow route in the atrium and mixing between balconies and the atrium. However these results could potentially give the same detailed results I am looking for.</SPAN></P>
<P><SPAN lang=DA style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: 'Verdana', 'sans-serif'">Finally has any one worked on an uncertainty analysis of these coupling methods illustrating first of all the uncertainty in the results as well as the sensitivity in the input parameters?</SPAN></P>
<P><SPAN lang=DA style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: 'Verdana', 'sans-serif'">Has anyone done something like this before and what tools were used? I have been given free hands with regards to choice of software so any feedback on this subject will be useful. I'm really looking forward to hear from you :-)</SPAN></P>
<P><B><SPAN lang=DA style="FONT-SIZE: 7.5pt; FONT-FAMILY: 'Verdana', 'sans-serif'">Kind regards</SPAN></B><SPAN lang=DA> </SPAN></P>
<P class=MsoNormal> </P>
<P><B><SPAN lang=DA style="FONT-SIZE: 7.5pt; FONT-FAMILY: 'Verdana', 'sans-serif'">Frederik Vildbrad Winther (FRW)</SPAN></B><SPAN lang=DA><BR></SPAN><SPAN lang=DA style="FONT-SIZE: 7.5pt; FONT-FAMILY: 'Verdana', 'sans-serif'">M.Sc., Indoor Environments</SPAN> <BR><SPAN lang=DA style="FONT-SIZE: 7.5pt; FONT-FAMILY: 'Verdana', 'sans-serif'">Indoor Climate and HVAC</SPAN> <BR><BR><SPAN lang=DA style="FONT-SIZE: 7.5pt; FONT-FAMILY: 'Verdana', 'sans-serif'">Rambøll Danmark A/S</SPAN> <BR><SPAN lang=DA style="FONT-SIZE: 7.5pt; FONT-FAMILY: 'Verdana', 'sans-serif'">Teknikerbyen 31</SPAN> <BR><SPAN lang=DA style="FONT-SIZE: 7.5pt; FONT-FAMILY: 'Verdana', 'sans-serif'">DK-2830 Virum</SPAN> <BR><A href="http://www.ramboll.dk/" target=_blank rel=nofollow><SPAN lang=DA style="FONT-SIZE: 7.5pt; FONT-FAMILY: 'Verdana', 'sans-serif'">http://www.ramboll.dk</SPAN></A><SPAN lang=DA><BR><BR></SPAN><SPAN lang=DA style="FONT-SIZE: 7.5pt; FONT-FAMILY: 'Verdana',
'sans-serif'">Direct 4598 6254<BR></SPAN><A href="mailto:frw@ramboll.dk" target=_blank rel=nofollow ymailto="mailto:frw@ramboll.dk"><SPAN lang=DA style="FONT-SIZE: 7.5pt; FONT-FAMILY: 'Verdana', 'sans-serif'">mailto:frw@ramboll.dk</SPAN></A><SPAN style="FONT-SIZE: 7.5pt; FONT-FAMILY: 'Verdana', 'sans-serif'"> </SPAN><BR><SPAN lang=DA style="FONT-SIZE: 7.5pt; FONT-FAMILY: 'Verdana', 'sans-serif'">__________________________________________________ </SPAN><BR><SPAN lang=DA style="FONT-SIZE: 7.5pt; FONT-FAMILY: 'Verdana', 'sans-serif'">Knowledge taking people further---</SPAN><SPAN lang=DA> </SPAN></P></DIV></DIV></DIV></div><br>
</body></html>