modelDoorDiscretized

Door model using discretization along height coordinate

Extends from Buildings.Airflow.Multizone.BaseClasses.TwoWayFlowElementBuoyancy.

Information

This is a partial model for the bi-directional air flow through a door.

To compute the bi-directional flow, the door is discretize along the height coordinate, and uses an orifice equation to compute the flow for each compartment.

The compartment area dA is a variable, which allows using the model for a door that can be open or closed.

Parameters

Type	Name	Default	Description
Integer	nCom	10	Number of compartments for the discretization
Modelica.Units.SI.PressureDifference	dp_turbulent	0.01	Pressure difference where laminar and turbulent flow relation coincide. Recommended: 0.01

Components

Type	Name	Default	Description
Modelica.Units.SI.PressureDifference[nCom]	dpAB		Pressure difference between compartments
Modelica.Units.SI.Velocity[nCom]	v		Velocity in compartment from A to B
Modelica.Units.SI.Velocity	vTop		Velocity at top of opening from A to B
Modelica.Units.SI.Velocity	vBot		Velocity at bottom of opening from A to B
Modelica.Units.SI.Length	dh	hOpe/nCom	Height of each compartment

Revisions

September 19, 2025, by Michael Wetter:
Introduced protected parameter sqrt_dp_turbulent, which is needed to improve computing efficiency if flow exponent is 0.5.
This is for IBPSA, #2043.
October 29, 2024, by Klaas De Jonge:
Unprotected dh and changed prefixes of dh,hAg and hBg to input.
This is for #1935.
January 8, 2019, by Michael Wetter:
Moved parameter CD from Buildings.Airflow.Multizone.BaseClasses.DoorDiscretized to Buildings.Airflow.Multizone.DoorDiscretizedOpen.
This is for #971.
June 27, 2018, by Michael Wetter:
Corrected old parameter annotation.
June 6, 2018, by Michael Wetter:
Removed term that assures non-zero flow rate in each path, and reformulated flow balance to ensure that model is symmetric. This is for #937.
January 22, 2016, by Michael Wetter:
Corrected type declaration of pressure difference. This is for #404.
September 26, 2013 by Michael Wetter:
Added missing each keyword.
December 14, 2012 by Michael Wetter:
Renamed protected parameters for consistency with the naming conventions.
December 6, 2011 by Michael Wetter:
Removed protected variable rhoAve.
August 12, 2011 by Michael Wetter:
Changed model to use the new function Buildings.Airflow.Multizone.BaseClasses.powerLawFixedM.
July 20, 2010 by Michael Wetter:
Migrated model to Modelica 3.1 and integrated it into the Buildings library.
February 8, 2005 by Michael Wetter:
Released first version.