<html><head><style type="text/css"><!-- DIV {margin:0px;} --></style></head><body><div style="font-size: 13px;color: rgb(0, 0, 0);font-family: arial, sans-serif;">Assuming that that temperature is uniformly distributed over the stack, the height of the neutral pressure line will not change. Obviously the maximum pressures at the top and bottom of stack will change, but equally so that the neutral pressure line does not change. The height of neutral pressure would primarily be affected by variations between pressure drops, or aperture area between the top and the bottom of the stack. So, somebody opens all of the windows on the top floor, the neutral pressure height rises. <br><br><blockquote style="padding-left: 5px; margin-left: 0px; border-left: #0000ff 2px solid; font-weight: normal; font-style: normal; text-decoration: none; font-size: 10pt; font-family: arial,sans-serif; color: black;">-----Original Message-----
<br>From: Vikram Sami via Bldg-sim <bldg-sim@lists.onebuilding.org>
<br>Sent: Dec 7, 2016 12:40 PM
<br>To: "bldg-sim@lists.onebuilding.org" <bldg-sim@lists.onebuilding.org>
<br>Subject: [Bldg-sim] Stack effect question
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<p class="MsoNormal">This might be a basic question.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Does the internal temperature of a stack affect the neutral pressure height? Would adding heat into a stack cause the neutral pressure point to rise? Instinctively I think it does, but I cannot find the equation for this.
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<p class="MsoNormal">Appreciate any feedback<o:p></o:p></p>
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<p class="MsoNormal">Thanks<o:p></o:p></p>
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<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial",sans-serif">Vikram Sami, AIA, BEMP, LEED AP BD+C</span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial",sans-serif">Director of Building Performance
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