AixLib.Fluid.Sources.Boundary_pT

# .AixLib.Fluid.Sources.Boundary_pT

Boundary with prescribed pressure, temperature, composition and trace substances

## Information

Defines prescribed values for boundary conditions:

- Prescribed boundary pressure.
- Prescribed boundary temperature.
- Boundary composition (only for multi-substance or trace-substance flow).

#### Typical use and important parameters

If `use_p_in` is false (default option), the `p` parameter is used as boundary pressure, and the `p_in` input connector is disabled; if `use_p_in` is true, then the `p` parameter is ignored, and the value provided by the input connector is used instead.

The same applies to the temperature T, composition Xi or X and trace substances C.

#### Options

Instead of using `Xi_in` (the independent composition fractions), the advanced tab provides an option for setting all composition fractions using `X_in`. `use_X_in` and `use_Xi_in` cannot be used at the same time.

Parameter `verifyInputs` can be set to `true` to enable a check that verifies the validity of the used temperatures and pressures. This removes the corresponding overhead from the model, which is a substantial part of the overhead of this model. See #882 for more information.

Note, that boundary temperature, mass fractions and trace substances have only an effect if the mass flow is from the boundary into the port. If mass is flowing from the port into the boundary, the boundary definitions, with exception of boundary pressure, do not have an effect.

## Revisions

- March 11, 2024, by Michael Wetter:
  Corrected use of `HideResult`.
  This is for #1850.
- February 25, 2020, by Michael Wetter:
  Changed icon to display its operating state.
  This is for #1294.
- Juni 7, 2019, by Michael Wetter:
  Added constant boolean expressions to avoid a potential string comparison in an equation section.
  See #1148.
- Juni 4, 2019, by Filip Jorissen:
  Added check for the value of `p` and `p_in`.
  See #1148.
- January 25, 2019, by Michael Wetter:
  Refactored use of base classes.
  See #1072.
- February 2nd, 2018 by Filip Jorissen
  Made `medium` conditional and refactored inputs. See #882.
- April 18, 2017, by Filip Jorissen:
  Changed `checkBoundary` implementation such that it is run as an initial equation when it depends on parameters only. See #728.
- January 26, 2016, by Michael Wetter:
  Added `unit` and `quantity` attributes.
- May 29, 2014, by Michael Wetter:
  Removed undesirable annotation `Evaluate=true`.
- September 29, 2009, by Michael Wetter:
  First implementation. Implementation is based on `Modelica.Fluid`.

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