modelCanopyFreeConvection
Leaves heat exchange by free convection with air
Extends from Modelica.Thermal.HeatTransfer.Interfaces.Element1D (Partial heat transfer element with two HeatPort connectors that does not store energy).
Information
The heat exchange coefficient on the leaves of tomato crop was derived experimentally by [1]. However, due to the lack of required input data to compute it, in this model it is simplified to a constant value. Given that this coefficient is expressed per unit of leaf area, in order to compute the global heat exchange coefficient, the LAI, defined as the leaf area per unit of ground area, is a required input.
[1] C. Stanghellini. Transpiration of greenhouse crops : an aid to climate management. PhD thesis, Wageningen University, 1987.
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| Modelica.Units.SI.Area | A | floor surface | |
| Modelica.Units.SI.CoefficientOfHeatTransfer | U | 5 | Leaves heat transfer coefficient |
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 | |
| Real | LAI | 1 | Leaf Area Index |
| Modelica.Units.SI.CoefficientOfHeatTransfer | HEC_ab |