modelStaticPipe
Information
This components allows to model the mass flow rate through a pipe from a pressure difference at boundaries and the pressure loss coefficient ksi. The flow regime is steady state.
ksi expresses how many dynamic pressure is lost. It is assumed to be constant and therefore independent of the flow regime.
The mass flow rate relation derives:
Where:
-
dpis the pressure difference between port_a.p and port_b.p -
ksiis the pressure loss coefficient -
dis the upstream density -
Velis fluid velocity -
m_flowis the mass flow rate through the pipe -
Ais cross section of the pipe
To avoid infinite derivative at dp=0, The square root is replaced by the function regRoot2 of the MSL that replace the square root by a polynomial expression to insure a finite derivative. The threshold to switch between the polynom and the square root is abs(dp≤0.1) Pa
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| Modelica.SIunits.PressureDifference | dp_small | 0.01 | |
| Geometry | |||
| Modelica.SIunits.Area | A | Inner cross section area | |
| Flow | |||
| Real | ksi | 1 | dynamic pressure loss |
Connectors
| Type | Name | Default | Description |
|---|---|---|---|
| Modelica.Fluid.Interfaces.FluidPort_a | port_a | ||
| Modelica.Fluid.Interfaces.FluidPort_b | port_b |
Components
| Type | Name | Default | Description |
|---|---|---|---|
| Modelica.SIunits.Density | d_a | Density if flow positive at port_a | |
| Modelica.SIunits.Density | d_b | Density if flow positive at port_b | |
| Modelica.SIunits.PressureDifference | dp | ||
| Modelica.SIunits.Velocity | Vel | ||
| Modelica.SIunits.MassFlowRate | m_flow | Aperture flow kg/s |
Contents
| Name | Description |
|---|---|
 Medium |