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<p class="MsoNormal"><span style="color:#1F497D">I am looking for some guidance in selecting my boundary conditions when modeling a glazing systems in THERM.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">A long time ago I attended a THERM training session where they stated that for general projects it was not necessary to model a system to NFRC 100 boundary conditions. They stated we should use a “Simplified”
boundary condition model rather than a “comprehensive: one and that a typical, acceptable interior air film coefficient is 8.3 W/mK.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">Recently a discussion came up that we should use the “Comprehensive” boundary condition model for every simulation, and that the interior film coefficient should be closer to 3. I did a couple of different runs
varying the boundary conditions and the results change significantly. See image below:<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal" style="margin-top:12.0pt"><img width="1181" height="414" id="Picture_x0020_1" src="cid:image001.jpg@01CCD06B.F2C6BA90"><span style="color:#1F497D"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">Run 01 is using the default NFRC Conditions. Run 04 is how I was previously taught to do the simulation. Runs 02 and 03 are other variations.
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">What happens to the model when you set the radiation model to to “Automatic Enclosure Model” compared to “Simplified”?<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">What boundary conditions (with respect to film coefficients and radiation models) should be used to generate conservative, but realistic results.?<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">Thanks<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">Nastassja Pearson<o:p></o:p></span></p>
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