modelHotWaterRadiator
Information
Hypothesis and equations
Hot water radiator taking into account inertias of water filling and radiator body. Room heating needs and radiator control have to be modelled apart from this model as it does not include any control.
The radiator is discretized in horizontal slices with uniform temperature (water + metal). This discretization is detailed in document "Type 13 Radiateur" [EDF2000].
The model is based on dissipated power calculation from French standard with a power law [NF-047]. According to this standard, radiator parameters are standardized to a rated power for which the gap between mean radiator temperature and mean air temperature is 50°K.
Bibliography
Detailed modelling in note : H-E14-2011-01955-FR
[NF-047] NF / AERAULIQUE ET THERMIQUES - Radiateurs, convecteurs et panneaux rayonnants de plafonds - Annexe n°9
[EDF2000] Type 13, Radiateur, Document interne EDF sur la modélisation d'un radiateur à eau, corrigé par M. Raguin
Instructions for use
Setting of inertia is simplified thanks to a list of correlations by radiator type (cast iron, aluminium, steel) from manufactures data.
Known limits / Use precautions
For specific studies needing accuracy, it is possible to develop a pre-processor in order to determine the best value for the corrective coefficient CoeffCorrectif.
In further modelling, if the radiative dissipation become sensitive in comparison with conductive dissipation, it would be good to refine FracRad parameter in order to make it dependent on radiator temperature.
Validations
Validated model - Hubert Blervaque, Sila Filfli 07/2011
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Licensed by EDF under a 3-clause BSD-license
Copyright © EDF 2009 - 2023
BuildSysPro version 3.6.0
Author : Hubert BLERVAQUE, Sila FILFLI, EDF (2011)
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Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| Radiator technology | |||
| Integer | Type | 2 | Radiator type for determination of inertia (water filling and radiator body) by a correlation based on rated power |
| CERTITA given parameters for a DeltaTnom = 50°C | |||
| SI.EnergyFlowRate | Pnom | 1000 | Radiator rated power. Certita database gives manufacturers data certified standard NF (French standard) for a 50°C temperature gap |
| SI.TemperatureDifference | DeltaTnom | 50 | According to water temperature of distribution system, temperature gap between air and radiator (by default, in Certita conditions : 50°C) |
| Real | nNom | 1.29 | Slope of emission line |
| Other parameters | |||
| Integer | N | 10 | Number of discretized elements |
| Real | CoeffCorrectif | 1.1 | For a low number of elements (<20), radiator rated power can be corrected with this parameter |
| Real | FracRad | 0.35 | Part of radiative emission in comparison with the convective part (between 0 and 1) |
Connectors
| Type | Name | Default | Description |
|---|---|---|---|
| BuildSysPro.BaseClasses.HeatTransfer.Interfaces.HeatPort_b | Rad | Radiative part of dissipated heat to the room | |
| BuildSysPro.BaseClasses.HeatTransfer.Interfaces.HeatPort_b | Conv | Convective part of dissipated heat to the room | |
| Modelica.Blocks.Interfaces.RealInput[2] | WaterIn | Vector containing 1- the input fluid temperature (K), 2- the input fluid flow rate (kg/s) | |
| Modelica.Blocks.Interfaces.RealOutput[2] | WaterOut | Vector containing 1- the output fluid temperature (K), 2- the output fluid flow rate (kg/s) |
Components
| Type | Name | Default | Description |
|---|---|---|---|
| SI.Temperature | Ta | Temperature of the room | |
| SI.Temperature | Te_m | mean temperature of water | |
| SI.TemperatureDifference | DeltaT_m | Mean temperature difference between an element of the radiator and the room | |
| SI.EnergyFlowRate | Ptot | Puissance dissipée par le radiateur à la pièce |