.AixLib.Airflow.AirHandlingUnit.ModularAirHandlingUnit.Components.RecircFlap

Information

This model describes an idealized model for a recirculation flap. Depending on the flap position the outdoor air is mixed with the exhaust air.

The flap position can be set by the input parameter flapPosition where 0 means the flap is fully closed and 1 means fully open.

The mixture of the streams is calculated using the Richmann's mixing rule.

T_OdaOut=(ṁ_OdaIn · c_p,OdaIn · T_OdaIn+ ṁ_EtaRecirc · c_p,EtaIn · T_EtaIn) ⁄ (ṁ_OdaIn · c_p,OdaIn + ṁ_EtaRecirc · c_p,EtaIn)

X_OdaOut=(ṁ_OdaIn · X_OdaIn+ ṁ_EtaRecirc · X_EtaIn) ⁄ (ṁ_OdaIn + ṁ_EtaRecirc)

The recirculating mass flow rate of the exhaust air is calculated using a parameter splitFactor. The splitFactor is calculated by the flapPosition depending on the calculation mode. By default the relation between these is linear.

ṁ_EtaRecirc=ṁ_EtaIn · splitFactor

Contents

Name	Description
PartialPressureDrop

Revisions

• May 2019, by Ervin Lejlic:
  First implementation.
• May 2019, by Martin Kremer:
  Changing variable names. Adding possibility for other relation between flap position and volume flow through flap than linear.