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AirFlow Network Window/Door Opening

asked 2020-05-27 08:56:28 -0600

shifty21 gravatar image

updated 2020-05-28 09:22:38 -0600

Hi everyone,

I am trying to control the window open, close based on temperature or humidity or any other available sensor. Using the reference file EMSAirflowNetworkOpeningControlByHumidity.idf provided in examples

As mentioned in the Application guide Airflow Network Opening provides an actuator called "AirFlow Network Window/Door Opening, Venting Opening Factor". For this actuator to work we need either of AirflowNetwork:MultiZone:Component: DetailedOpening or AirflowNetwork:MultiZone:Component: SimpleOpening. I have defined both of there but I couldn't find this actuator in the EDD file.

I am attaching my IDF and EDD file with this.

There are no errors but the actuator is not available to use as well. Any help appreciated!

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answered 2020-05-28 08:50:09 -0600

In the AirflowNetwork:SimulationControl object, the AirflowNetwork Control input field is set to NoMultizoneOrDistribution. This effectively turns off AirFlow Network (AFN), even if you have AFN objects defined in the input file (see below).

  AirflownetworkSimulation,!- Name
  NoMultizoneOrDistribution,  !- AirflowNetwork Control
  SurfaceAverageCalculation,  !- Wind Pressure Coefficient Type
  OpeningHeight,           !- Height Selection for Local Wind Pressure Calculation
  LowRise,                 !- Building Type
  500,                     !- Maximum Number of Iterations {dimensionless}
  ZeroNodePressures,       !- Initialization Type
  0.0001,                  !- Relative Airflow Convergence Tolerance {dimensionless}
  0.000001,                !- Absolute Airflow Convergence Tolerance {kg/s}
  -.5,                     !- Convergence Acceleration Limit {dimensionless}
  ,                        !- Azimuth Angle of Long Axis of Building {deg}
  1,                       !- Ratio of Building Width Along Short Axis to Width Along Long Axis
  No,                      !- Height Dependence of External Node Temperature
  SkylineLU;               !- Solver

To use AFN to model window openings, you should change the AirflowNetwork Control input field to MultiZoneWithoutDistribution if you DO NOT want AFN calculations for HVAC systems (duct leakage, etc.). If you want AFN calculations for HVAC systems, then you should set this input field to either the MultiZoneWithDistribution or MultiZoneWithDistributionOnlyDuringFanOperation options instead.

Once you make this change and "turn on" AFN, I would recommend using the EMSAirflowNetworkOpeningControlByHumidity.idf example file as a reference in case there are warnings and errors related to AFN.

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Thanks a lot Aaron! that did the job, I thought that since I only have one zone I should not select that option.

shifty21 gravatar image shifty21  ( 2020-05-28 12:46:50 -0600 )edit

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Asked: 2020-05-27 08:56:28 -0600

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Last updated: May 28 '20