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Hello everyone,<br><br>I'm setting up a fairly rudimentary airflow network, in which two zone air nodes exchange air with a third node that is intended to mix the air and send it back to the nodes. A fixed volume rate component moves the air. The "mixing" node was assigned to known boundary conditions of P=0 Pa, T=20C. However, after several tries, I continue to get the following message for each timestep:<br><br>Please check (in the following order) that: <br> - each node has some flow path to a boundary pressure and <br> - iteration convergence control is not too strict. <br> Day 2 Month 1 Hour 24.000: 100 iterations; flows solution failed <br><br>I assume the first issue is triggering the message. I would have thought that having the mixing node at known conditions would alleviate this error. <br><br>Any thoughts? (I realize this could be accomplished in the operations file, but I want something more sophisticated eventually.)<br><br>The afn file is below.<br><br>
Thanks very much!<br><br>Liam O'Brien <br><br>----------------<br><br> 3 1 4 1.000 (nodes, components, connections, wind reduction)<br> Node Fld. Type Height Temperature Data_1 Data_2<br> south 1 0 2.5000 20.000 0.0000 250.01 <br> north 1 0 2.5000 20.000 0.0000 250.01 <br> Mixing 1 2 20.000 0.0000 0.0000 2.0000 <br> Component Type C+ L+ Description<br> Circulation 30 2 0 Constant vol. flow rate component m = rho.a <br> 1. 0.200000003<br> +Node dHght -Node dHght via Component<br> south 8.750 Mixing -8.750 Circulation <br> north 8.750 Mixing -8.750 Circulation <br> Mixing -8.750 south 8.750 Circulation <br> Mixing -8.750 north 8.750 Circulation <br><br /><hr />Windows Live helps you keep up with all your friends, <a href='http://go.microsoft.com/?linkid=9660824' target='_new'>in one place.</a></body>
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