modelConnection2PipePlugFlow_v
Model for connecting an agent to a two-pipe distribution network, using plug flow pipe models in the main line
Extends from Buildings.DHC.Networks.BaseClasses.PartialConnection2Pipe.
Information
This model represents the supply and return lines to connect an agent (e.g. an energy transfer station) to a two-pipe main distribution system. A plug flow pipe model Buildings.Fluid.FixedResistances.PlugFlowPipe that includes pressure drop, heat transfer, and transport delays is used in the main distribution line, but not in the connection to the building, as the latter is typically short.
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| Modelica.Units.SI.Length | lDis | Length of the distribution pipe before the connection | |
| Modelica.Units.SI.Length | dIns | Thickness of pipe insulation, used to compute R | |
| Modelica.Units.SI.ThermalConductivity | kIns | Heat conductivity of pipe insulation, used to compute R | |
| Modelica.Units.SI.Velocity | v_nominal | 1.5 | Velocity at m_flow_nominal (used to compute default value for hydraulic diameter dh) |
| Modelica.Units.SI.Height | roughness | 2.5e-5 | Average height of surface asperities (default: smooth steel pipe) |
| Modelica.Units.SI.SpecificHeatCapacity | cPip | 2300 | Specific heat of pipe wall material. 2300 for PE, 500 for steel |
| Modelica.Units.SI.Density | rhoPip | 930 | Density of pipe wall material. 930 for PE, 8000 for steel |
| Modelica.Units.SI.Length | thickness | 0.0035 | Pipe wall thickness |
Components
| Type | Name | Default | Description |
|---|---|---|---|
| Modelica.Thermal.HeatTransfer.Interfaces.HeatPort_a | heatPortDis | Heat transfer to or from surroundings for distribution pipe(positive if pipe is colder than surrounding) | |
| Modelica.Thermal.HeatTransfer.Interfaces.HeatPort_a | heatPortRet | Heat transfer to or from surroundings for return pipe (positive if pipe is colder than surrounding) |
Revisions
-
March 15, 2024, by David Blum:
Renamed. This is for issue 3712. -
June 14, 2023, by David Blum:
Fix redeclare of dis pipe models in connections. -
January 2, 2023, by Kathryn Hinkelman:
First implementation.