modelStratifiedUnloadAtMinimumTemperature
Example that demonstrates how to draw from a hot water tank at the minimum temperature
Extends from Modelica.Icons.Example (Icon for runnable examples).
Information
Example for tank model that has three outlets, each with a valve. The valve at the bottom opens when the temperature in that tank segment is sufficiently warm to serve the load. The tank in the middle also opens when its tank temperature is sufficiently high, but only if the valve below is closed. Finally, the valve at the top only opens if no other valve is open. Hence, there is always exactly one valve open. On the right-hand side of the model is a heater that adds heat to the bottom of the tank if the top tank segment is below the set point temperature.
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| Modelica.Units.SI.Volume | VTan | 3 | Tank volume |
| Modelica.Units.SI.MassFlowRate | m_flow_nominal | 3*1000/3600 | Nominal mass flow rate |
| Integer | nSeg | 5 | Number of volume segments |
Components
| Type | Name | Default | Description |
|---|---|---|---|
| Buildings.Fluid.Storage.Stratified | tan | Hot water storage tank | |
| Buildings.Fluid.Sources.Boundary_pT | loa | Load (imposed by a constant pressure boundary condition and the flow of masSou) | |
| Buildings.Fluid.Sources.MassFlowSource_T | masSou | Mass flow rate into the tank | |
| Buildings.Fluid.Actuators.Valves.TwoWayLinear | valTop | Control valve at top | |
| Buildings.Fluid.Actuators.Valves.TwoWayLinear | valMid | Control valve at middle | |
| Buildings.Fluid.Actuators.Valves.TwoWayLinear | valBot | Control valve at bottom | |
| Modelica.Thermal.HeatTransfer.Sensors.TemperatureSensor | TMid | Temperature tank middle | |
| Modelica.Thermal.HeatTransfer.Sensors.TemperatureSensor | TBot | Temperature tank bottom | |
| Modelica.Blocks.Logical.Hysteresis | onOffBot | Controller for valve at bottom | |
| Buildings.Fluid.Sensors.TemperatureTwoPort | senTem | Outflowing temperature | |
| Modelica.Blocks.Logical.Hysteresis | onOffMid | Controller for valve at middle of tank | |
| Modelica.Blocks.Logical.And | and2 | And block to compute control action for middle valve | |
| Modelica.Blocks.Math.BooleanToReal | yMid | Boolean to real conversion for valve at middle | |
| Modelica.Blocks.Math.BooleanToReal | yTop | Boolean to real conversion for valve at top | |
| Modelica.Blocks.Logical.Nor | nor | Nor block for top-most control valve | |
| Modelica.Blocks.Logical.Not | not1 | Not block to negate control action of upper level control | |
| Modelica.Thermal.HeatTransfer.Sources.PrescribedHeatFlow | hea | Heat input at the bottom of the tank | |
| Modelica.Thermal.HeatTransfer.Sensors.TemperatureSensor | TTop | Temperature tank top | |
| Modelica.Blocks.Logical.Hysteresis | onOffHea | Controller for heater at bottom | |
| Modelica.Blocks.Math.BooleanToReal | yHea | Boolean to real for valve at bottom | |
| Modelica.Blocks.Math.BooleanToReal | yBot | Boolean to real conversion for valve at bottom |
Contents
| Name | Description |
|---|---|
 Medium | Medium model |
Revisions
-
June 7, 2018 by Filip Jorissen:
Copied model from Buildings and update the model accordingly by removing CDL blocks. This is for #314. -
June 1, 2018, by Michael Wetter:
First implementation.
This is for issue 1182.