modelFreeVentilation
Heat exchange by ventilation
Extends from Modelica.Thermal.HeatTransfer.Interfaces.Element1D (Partial heat transfer element with two HeatPort connectors that does not store energy).
Information
The heat transfer between the inside and outside air due to natural ventilation is computed as a function of the air exchange rate.
This model also takes into account the leakage rate through the greenhouse structure, which is dependent on the wind speed (input of the model) and the leakage coefficient of the greenhouse (parameter of the model, characteristic of its structure).
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| Modelica.Units.SI.Area | A | floor surface | |
| Modelica.Units.SI.Angle | phi | 25/180*Modelica.Constants.pi | inclination of the roof (0 if horizontal, 25 for typical cover) |
| Real | fr_window | 0.078 | number of windows per m2 greenhouse |
| Modelica.Units.SI.Length | l | length of the window | |
| Modelica.Units.SI.Length | h | width of the window | |
| Real | f_leakage | 1.5e-4 | Greenhouse leakage coefficient |
| Boolean | thermalScreen | false | presence of a thermal screen in the greenhouse |
| Boolean | topAir | false | False for: Main air zone; True for: Top air zone |
Connectors
| Type | Name | Default | Description |
|---|---|---|---|
| HeatPort_a | port_a (from Element1D) | ||
| HeatPort_b | port_b (from Element1D) |
Components
| Type | Name | Default | Description |
|---|---|---|---|
| SI.HeatFlowRate | Q_flow (from Element1D) | Heat flow rate from port_a -> port_b | |
| SI.TemperatureDifference | dT (from Element1D) | port_a.T - port_b.T | |
| Modelica.Units.SI.Angle | theta_l | 0 | window opening at the leeside side |
| Modelica.Units.SI.Angle | theta_w | 0 | window opening at the windward side |
| Modelica.Units.SI.Velocity | u | 0 | Wind speed |
| Modelica.Units.SI.CoefficientOfHeatTransfer | HEC_ab | ||
| Modelica.Units.SI.Density | rho_air | 1.2 | |
| Modelica.Units.SI.SpecificHeatCapacity | c_p_air | 1005 | |
| Real | f_vent | ||
| HeatAndVapourTransfer.VentilationRates.NaturalVentilationRate_1 | airExchangeRate |