Enabled filter to avoid large flow rates during fan switch-off

lbl-srg · Nov 17, 2017 · bc1f838 · bc1f838
1 parent 6fd93f7
commit bc1f838
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diff --git a/Buildings/Examples/DualFanDualDuct/ClosedLoop.mo b/Buildings/Examples/DualFanDualDuct/ClosedLoop.mo
@@ -101,20 +101,20 @@ model ClosedLoop "Closed loop model of a dual-fan dual-duct system"
   Buildings.Fluid.Movers.SpeedControlled_y fanSupHot(
     redeclare package Medium = MediumA,
     per(pressure(V_flow=mAirHot_flow_nominal/1.2*{0,2}, dp=600*{2,0})),
-    energyDynamics=Modelica.Fluid.Types.Dynamics.FixedInitial,
-    use_inputFilter=false) "Supply air fan for hot deck"
+    energyDynamics=Modelica.Fluid.Types.Dynamics.FixedInitial)
+                           "Supply air fan for hot deck"
     annotation (Placement(transformation(extent={{300,-10},{320,10}})));
   Buildings.Fluid.Movers.SpeedControlled_y fanSupCol(
     redeclare package Medium = MediumA,
     per(pressure(V_flow=mAirCol_flow_nominal/1.2*{0,2}, dp=600*{2,0})),
-    energyDynamics=Modelica.Fluid.Types.Dynamics.FixedInitial,
-    use_inputFilter=false) "Supply air fan for cold deck"
+    energyDynamics=Modelica.Fluid.Types.Dynamics.FixedInitial)
+                           "Supply air fan for cold deck"
     annotation (Placement(transformation(extent={{302,-160},{322,-140}})));
   Buildings.Fluid.Movers.SpeedControlled_y fanRet(
     redeclare package Medium = MediumA,
     per(pressure(V_flow=m_flow_nominal/1.2*{0,2}, dp=100*{2,0})),
-    energyDynamics=Modelica.Fluid.Types.Dynamics.FixedInitial,
-    use_inputFilter=false) "Return air fan"
+    energyDynamics=Modelica.Fluid.Types.Dynamics.FixedInitial)
+                           "Return air fan"
     annotation (Placement(transformation(extent={{360,150},{340,170}})));
   Buildings.Fluid.Sources.FixedBoundary sinHea(
     redeclare package Medium = MediumW,
@@ -1203,6 +1203,14 @@ shading devices, Technical Report, Oct. 17, 2006.
 </html>", revisions="<html>
 <ul>
 <li>
+November 17, 2017, by Michael Wetter:<br/>
+Enabled filters at fan control signal. This avoids a sharp change in fan speed,
+which led to very large mass flow rates between the hot and cold deck fan
+when they were switched off.
+This model now works with JModelica with the CVode solver and <i>10<sup>-8</sup></i>
+tolerance.
+</li>
+<li>
 May 19, 2016, by Michael Wetter:<br/>
 Set <code>use_inputFilter=false</code> in fan models to avoid a large
 increase in computing time when simulated between <i>t=1.60E7</i>