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<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>Hello,</span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'> </span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>I am using IES to conduct a CFD model on a
long and narrow room (283ft by 60ft) with three large ducts (square 4ft by 4ft)
running along the ceiling (280ft long, 28ft off the floor). I have 18 diffusers
equally spaced along each of the three 280ft ducts for a total of 54. Each
diffuser has a CFM of 1110, an area of 3.75 sf, and a discharge velocity of 300
fpm. There is a single return grill at one end of the building. </span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'> </span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>My problem is: when I look at the velocity
vectors in the MicroFlo Viewer some of the diffusers have the air flowing
backwards or into the diffuser, not flowing out as it is supposed to. This
occurs across all three duct lengths at the same diffuser location. </span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'> </span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>Has anyone else run into this and have
they resolved the issue? IES took my model and made changes to it only to
find that they could not fix it. </span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'> </span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>Thank you in advance for any advice, </span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>Josh</span></font></p>
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10.0pt;font-family:Arial;color:navy'> </span></font></p>
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<p class=MsoNormal><font size=2 color=navy face="Times New Roman"><span
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<p class=MsoNormal><font size=2 color=navy face="Times New Roman"><span
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<p class=MsoNormal><font size=2 color=navy face="Times New Roman"><span
style='font-size:10.0pt;color:navy'>274 Summer Street
Boston, MA 02210 </span></font></p>
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<p class=MsoNormal><font size=2 color=navy face="Times New Roman"><span
style='font-size:10.0pt;color:navy'>Tel: (617) 423-7423 </span></font></p>
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<p class=MsoNormal><font size=2 color=navy face="Times New Roman"><span
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