modelConnection1Pipe_R

Model for connecting an agent to the DHC system

Extends from Buildings.DHC.Networks.BaseClasses.PartialConnection1Pipe (Partial model for connecting an agent to a one-pipe distribution network).

Information

This model represents the supply and return lines to connect an agent (e.g., an energy transfer station) to a one-pipe main distribution system. The instances of the pipe model are autosized based on the pressure drop per pipe length at nominal flow rate based on the model Buildings.DHC.Networks.Pipes.PipeAutosize for the distribution line. The connection to the building as the length is typically relatively short so a losssless pipe is considered.

Parameters

TypeNameDefaultDescription
Booleanshow_entFlo (from PartialConnection1Pipe)falseSet to true to output enthalpy flow rate difference
Booleanshow_TOut (from PartialConnection1Pipe)falseSet to true to output temperature at connection outlet
Modelica.Units.SI.MassFlowRatemDis_flow_nominal (from PartialConnection1Pipe)Nominal mass flow rate in the distribution line
Modelica.Units.SI.MassFlowRatemCon_flow_nominal (from PartialConnection1Pipe)Nominal mass flow rate in the connection line
Realdp_length_nominal250Pressure drop per pipe length at nominal flow rate
Modelica.Units.SI.LengthlDisLength of the distribution pipe before the connection
Modelica.Units.SI.LengthdhDisHydraulic diameter of the distribution pipe
Assumptions
BooleanallowFlowReversal (from PartialConnection1Pipe)false= true to allow flow reversal, false restricts to design direction (port_a -> port_b)
Dynamics › Conservation equations
Modelica.Fluid.Types.DynamicsenergyDynamics (from PartialConnection1Pipe)Modelica.Fluid.Types.Dynamics.FixedInitialType of energy balance: dynamic (3 initialization options) or steady state
Advanced › Dynamics
Modelica.Fluid.Types.DynamicsmassDynamics (from PartialConnection1Pipe)energyDynamicsType of mass balance: dynamic (3 initialization options) or steady state, must be steady state if energyDynamics is steady state
Dynamics › Nominal condition
Modelica.Units.SI.Timetau (from PartialConnection1Pipe)10Time constant at nominal flow for dynamic energy and momentum balance

Connectors

TypeNameDefaultDescription
Modelica.Fluid.Interfaces.FluidPort_aport_aDis (from PartialConnection1Pipe)Distribution inlet port
Modelica.Fluid.Interfaces.FluidPort_bport_bDis (from PartialConnection1Pipe)Distribution outlet port
Modelica.Fluid.Interfaces.FluidPort_aport_aCon (from PartialConnection1Pipe)Connection return port
Modelica.Fluid.Interfaces.FluidPort_bport_bCon (from PartialConnection1Pipe)Connection supply port
Buildings.Controls.OBC.CDL.Interfaces.RealOutputmCon_flow (from PartialConnection1Pipe)Connection supply mass flow rate (measured)
Buildings.Controls.OBC.CDL.Interfaces.RealOutputdH_flow (from PartialConnection1Pipe)Difference in enthalpy flow rate between connection supply and return
Buildings.Controls.OBC.CDL.Interfaces.RealOutputmByp_flow (from PartialConnection1Pipe)Bypass mass flow rate
Buildings.Controls.OBC.CDL.Interfaces.RealOutputTOut (from PartialConnection1Pipe)Temperature in distribution line at connection outlet

Components

TypeNameDefaultDescription
Fluid.FixedResistances.JunctionjunConSup (from PartialConnection1Pipe)Junction with connection supply
Fluid.FixedResistances.JunctionjunConRet (from PartialConnection1Pipe)Junction with connection return
Model_pipDispipDis (from PartialConnection1Pipe)Distribution pipe
Model_pipConpipCon (from PartialConnection1Pipe)Connection pipe
Buildings.Fluid.Sensors.MassFlowRatesenMasFloCon (from PartialConnection1Pipe)Connection supply mass flow rate (measured)
Buildings.Fluid.Sensors.MassFlowRatesenMasFloByp (from PartialConnection1Pipe)Bypass mass flow rate (measured)
DifferenceEnthalpyFlowRatesenDifEntFlo (from PartialConnection1Pipe)Difference in enthalpy flow rate
Fluid.Sensors.TemperatureTwoPortsenTOut (from PartialConnection1Pipe)Temperature in distribution line at connection outlet

Revisions

  • March 15, 2024, by David Blum:
    Renamed. This is for issue 3712.
  • December 20, 2023, by Ettore Zanetti:
    This is for issue 3431.
  • February 23, 2021, by Antoine Gautier:
    First implementation.