modelAirRenewal
Extends from BuildSysPro.BaseClasses.HeatTransfer.Interfaces.Element1D (Partial heat transfer element with two HeatPort connectors that does not store energy).
Information
Simple air renewal model for a single zone
Hypothesis and equations
This model calculates an enthalpy flow between a single zone and outside. It assumes that the mass-balance is met.
The value of the volume flow rate can be controlled or fixed throughout the simulation.
The enthalpy flow is defined based on the energy balance:
The main assumptions are:
- the air temperature is uniform in a zone: well-mixed assumption
- the air specific heat capacity is considered constant cp = constant
- the air density in a zone is constant: rho = constant
In addition the power consumption could be calculated. The default value correspond to 0.334 W/m3.h (extraction fan).
Bibliography
Model TF5 from CLIM 2000
Instructions for use
This is a none directional model. The port_a can be connected to the thermal port of the Meteofile model and the port_b to the thermal port of a Zone model or vice versa. To use the ventilation scenario control use_Qv_in = true), connect a real source to the RealInput named Qv_in.
Known limits / Use precautions
This model describes the heat transfer corresponding to the air renewal (ventilation and infiltration). This component is particularly important during heating periods. It can represent both an air renewal between a room and outside, and an air renewal between two rooms. For large temperature differences, prefer a pressure and temperature model.
Do not considered infiltration when calculating the electric power consumption.
Validations
Validated model - Gilles Plessis 02/2012
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Licensed by EDF under a 3-clause BSD-license
Copyright © EDF 2009 - 2023
BuildSysPro version 3.6.0
Author : Gilles PLESSIS, EDF (2012)
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Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| Ventilation/infiltration | |||
| Boolean | use_Qv_in | false | Prescribed volume flow rate |
| Real | Qv | 0 | Constant volume flow rate for ventilation and/or infiltrations [m3/h] |
| Electric power consumption | |||
| Boolean | use_Pelec | false | Compute power consumption |
| Real | Pelec_spe | 0.334 | Specific power consumption for ventilation [W/m3.h] |
| Air properties | |||
| Modelica.Units.SI.Density | rhoair | 1.24 | Air density |
| Modelica.Units.SI.SpecificHeatCapacity | Cp | 1005 | Air specific heat capacity |
Connectors
| Type | Name | Default | Description |
|---|---|---|---|
| HeatPort_a | port_a (from Element1D) | ||
| HeatPort_b | port_b (from Element1D) | ||
| Modelica.Blocks.Interfaces.RealInput | Qv_in | Prescribed air flow rate[m3/h] | |
| Modelica.Blocks.Interfaces.RealOutput | PelecVentil | Electric power consumption [W] |
Components
| Type | Name | Default | Description |
|---|---|---|---|
| Modelica.Units.SI.HeatFlowRate | Q_flow (from Element1D) | Heat flow rate from port_a -> port_b | |
| Modelica.Units.SI.TemperatureDifference | dT (from Element1D) | port_a.T - port_b.T |
Revisions
Benoît Charrier 12/2015 : Ajout du calcul de la puissance électrique liée à la ventilation, activable depuis un booléen. La puissance calculée est accessible pour les deux modes : débit commandé ou non.