modelDifferentialPressure
Differential pressure sensor
Extends from Buildings.Templates.Components.Interfaces.PartialSensor (Interface class for sensor).
Information
This is a model for a differential pressure sensor that can be
enabled or disabled with the Boolean parameter have_sen.
If disabled, the control input variable y is removed
and the model simply consists of two fluid ports that are not connected
to each other and for which the following equations are used.
So the model must still be provided with pressure conditions
at each port.
// Zero flow equations
port_(a|b).m_flow = 0;
// No contribution of specific quantities
port_(a|b).h_outflow = 0;
port_(a|b).Xi_outflow = zeros(Medium.nXi);
port_(a|b).C_outflow = zeros(Medium.nC);
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| Assumptions | |||
| Boolean | allowFlowReversal (from PartialTwoPort) | true | = false to simplify equations, assuming, but not enforcing, no flow reversal |
| Nominal condition | |||
| Modelica.Units.SI.MassFlowRate | m_flow_nominal (from PartialTwoPortInterface) | Nominal mass flow rate | |
| Advanced | |||
| Modelica.Units.SI.MassFlowRate | m_flow_small (from PartialTwoPortInterface) | 1E-4*abs(m_flow_nominal) | Small mass flow rate for regularization of zero flow |
| Advanced › Diagnostics | |||
| Boolean | show_T (from PartialTwoPortInterface) | false | = true, if actual temperature at port is computed |
| Configuration | |||
| Boolean | have_sen (from PartialSensor) | true | Set to true for sensor, false for direct pass through |
| Boolean | isDifPreSen (from PartialSensor) | false | Set to true for differential pressure sensor, false for any other sensor |
| Graphics | |||
| Integer | text_rotation (from PartialSensor) | 0 | Text rotation angle in icon layer |
| Boolean | text_flip (from PartialSensor) | false | True to flip text horizontally in icon layer |
| Buildings.Templates.Components.Types.IntegrationPoint | icon_pipe (from PartialSensor) | Buildings.Templates.Components.Types.IntegrationPoint.None | Pipe symbol |
Connectors
| Type | Name | Default | Description |
|---|---|---|---|
| Modelica.Fluid.Interfaces.FluidPort_a | port_a (from PartialTwoPort) | Fluid connector a (positive design flow direction is from port_a to port_b) | |
| Modelica.Fluid.Interfaces.FluidPort_b | port_b (from PartialTwoPort) | Fluid connector b (positive design flow direction is from port_a to port_b) | |
| Buildings.Controls.OBC.CDL.Interfaces.RealOutput | y (from PartialSensor) | Connector for measured value |
Components
| Type | Name | Default | Description |
|---|---|---|---|
| Modelica.Units.SI.MassFlowRate | m_flow (from PartialTwoPortInterface) | port_a.m_flow | Mass flow rate from port_a to port_b (m_flow > 0 is design flow direction) |
| Modelica.Units.SI.PressureDifference | dp (from PartialTwoPortInterface) | port_a.p - port_b.p | Pressure difference between port_a and port_b |
| Medium.ThermodynamicState | sta_a (from PartialTwoPortInterface) | if allowFlowReversal then Medium.setState_phX(port_a.p, noEvent(actualStream(port_a.h_outflow)), noEvent(actualStream(port_a.Xi_outflow))) else Medium.setState_phX(port_a.p, noEvent(inStream(port_a.h_outflow)), noEvent(inStream(port_a.Xi_outflow))) | Medium properties in port_a |
| Medium.ThermodynamicState | sta_b (from PartialTwoPortInterface) | if allowFlowReversal then Medium.setState_phX(port_b.p, noEvent(actualStream(port_b.h_outflow)), noEvent(actualStream(port_b.Xi_outflow))) else Medium.setState_phX(port_b.p, noEvent(port_b.h_outflow), noEvent(port_b.Xi_outflow)) | Medium properties in port_b |
| Buildings.Fluid.Sensors.RelativePressure | senRelPre | Relative pressure sensor |