.Buildings.Obsolete.Controls.OBC.ASHRAE.G36_PR1.AHUs.MultiZone.VAV.SetPoints.OutdoorAirFlow.SumZone

Information

This sequence sums up the zone level minimum outdoor airflow setpoints, finds the maximum zone outdoor air fraction and the minimum zone ventilation efficiency. It collects zone level outputs and prepares inputs for specifying AHU level minimum outdoor air setpoint.

It requires following inputs from zone level calculation,

• Design zone peak occupancy, uDesZonPeaOcc,
• Population component of the breathing zone design outdoor airflow, VDesPopBreZon_flow,
• Area component of the breathing zone design outdoor airflow, VDesAreBreZon_flow,
• Design zone primary outdoor air fraction, uDesPriOutAirFra,
• Uncorrected outdoor airflow rate, VUncOutAir_flow,
• Primary outdoor air fraction, uPriOutAirFra,
• Primary airflow rate, VPriAir_flow,

and following input from AHU level calculation,

• Average AHU level outdoor air flow fraction plus 1, yAveOutAirFraPlu.

The sequence gives following outputs for AHU level calculation:

• Sum of the design population of the zones, ySumDesZonPop,
• Sum of the population component of the design breathing zone flow rate, VSumDesPopBreZon_flow,
• Sum of the area component of the design breathing zone flow rate, VSumDesAreBreZon_flow,
• Design system ventilation efficiency, yDesSysVenEff,

  First, compute the zone ventilation efficiency zonVenEff, for design purpose, as

      zonVenEff[i] = yAveOutAirFraPlu - uDesPriOutAirFra[i]
  

  where the uDesPriOutAirFra is the design zone outdoor airflow fraction. Then the design system ventilation efficiency yDesSysVenEff is

      yDesSysVenEff = min(zonVenEff[i]).
  

• Sum of the required uncorrected outdoor airflow rate, VSumUncOutAir_flow,
• Maximum zone outdoor air fraction, uOutAirFra_max,
• AHU level primary airflow rate, VSumSysPriAir_flow.

Revisions

• March 13, 2020, by Jianjun Hu:
  Separated from original sequence of finding the system minimum outdoor air setpoint.
  This is for #1829.