modelCollectorDistributor
Model of a collector/distributor with zero pressure drop between connections
Extends from Buildings.DHC.Networks.BaseClasses.PartialDistribution2Pipe (Partial model for two-pipe distribution network).
Information
This model represents a collector/distributor which connects
nCon hydronic circuits in parallel.
The pressure drop between each connection is assumed negligible
compared to the pressure drop in each circuit, and is set to zero
in the model.
By default,
-
there is no bypass flow (which can be added later by connecting
the ports
port_bDisSupandport_aDisRet), -
the nominal distribution mass flow rate
mDis_flow_nominalis equal to the sum of the nominal mass flow rate in each circuit. However, this parameter assigment is not final and it can be set for instance to a higher value to represent a primary overflow in a supply through loop.
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| Boolean | show_entFlo (from PartialDistribution2Pipe) | false | Set to true to output enthalpy flow rate difference at each connection |
| General | |||
| Integer | nCon (from PartialDistribution2Medium) | Number of connections | |
| Integer | iConDpSen (from PartialDistribution2Pipe) | nCon | Index of the connection where the pressure drop is measured |
| Assumptions | |||
| Boolean | allowFlowReversal (from PartialDistribution2Medium) | false | = true to allow flow reversal, false restricts to design direction (port_a -> port_b) |
| General › Nominal condition | |||
| Modelica.Units.SI.MassFlowRate | mDis_flow_nominal (from PartialDistribution2Pipe) | Nominal mass flow rate in the distribution line before the first connection | |
| Modelica.Units.SI.MassFlowRate[nCon] | mCon_flow_nominal (from PartialDistribution2Pipe) | Nominal mass flow rate in each connection line | |
| Modelica.Units.SI.MassFlowRate | mEnd_flow_nominal (from PartialDistribution2Pipe) | mDis_flow_nominal - sum(mCon_flow_nominal) | Nominal mass flow rate in the end of the distribution line |
| Modelica.Units.SI.MassFlowRate[nCon] | mDisCon_flow_nominal (from PartialDistribution2Pipe) | cat(1, {mDis_flow_nominal}, {mDis_flow_nominal - sum(mCon_flow_nominal[1:i]) for i in 1:(nCon - 1)}) | Nominal mass flow rate in the distribution line before each connection |
| Dynamics › Conservation equations | |||
| Modelica.Fluid.Types.Dynamics | energyDynamics (from PartialDistribution2Pipe) | Modelica.Fluid.Types.Dynamics.FixedInitial | Type of energy balance: dynamic (3 initialization options) or steady state |
| Dynamics › Nominal condition | |||
| Modelica.Units.SI.Time | tau (from PartialDistribution2Pipe) | 10 | Time constant at nominal flow for dynamic energy and momentum balance |
Connectors
Components
| Type | Name | Default | Description |
|---|---|---|---|
| Buildings.DHC.Networks.BaseClasses.PartialConnection2Pipe[nCon] | con (from PartialDistribution2Pipe) | Connection to agent | |
| Model_pipDis | pipEnd (from PartialDistribution2Pipe) | Pipe representing the end of the distribution line (after last connection) | |
| Fluid.Sensors.RelativePressure | senRelPre (from PartialDistribution2Pipe) | Relative pressure sensor |
Revisions
-
July 31, 2020, by Antoine Gautier:
First implementation.