# 7.38. Pressurization Model

This section is referenced in the following other sections

- Simulation Setup: Pressurization Zones

## 7.38.1. Pressurization Model

Scope

  Aria Region

Summary

  Parameters for the pressurization model

    begin Pressurization Model ModelName

       Coupling Algorithm {=} {coupled | segregated}

       Equation Of State {=} equationOfState...

       Excess Volume {=} excessVolume

       Excess Volume Temperature {=} excessVolumeTemperature

       Excess Volume Weight {=} excessVolumeWeight

       Initial Mixture Molecular Weight {=} initMMW

       Initial Pressure {=} initPressure

       Pressure Unit {=} pressureUnit

       Pressurization Source Blocks {=} sourceBlocks...

       Pressurized Blocks {=} pressurizedBlocks...

       Pressurized Bulk Nodes {=} pressurizedBulkNodes...

       Solver Name {=} solverName

       Temperature Averaging {=} ventingModel

       Venting Model {=} ventingModel

       Venting Model Property propertyName {=} propertyModelAndParams...

    end Pressurization Model ModelName

### 7.38.1.1. Line Commands

###### Coupling Algorithm

Syntax

  Coupling Algorithm {=} {coupled | segregated}

Summary

  This command specifies the coupling algorithm (COUPLED or SEGREGATED).

Parameter | Value | Default
--- | --- | ---
{=} | {= | are | is} | –
couplingAlg | {coupled | segregated} | COUPLED

###### Equation Of State

Syntax

  Equation Of State {=} equationOfState…

Summary

  Specifies the equation of state to use (Ideal_Gas, VanDerWaal, or BKWS). The gas constant is an optional argument (R = value), and defaults to 8314 J/kmol-K if omitted.

Parameter | Value | Default
--- | --- | ---
{=} | {= | are | is} | –
equationOfState | string… | –

###### Excess Volume

Syntax

  Excess Volume {=} excessVolume

Summary

  Specifies the volume of the excess volume. This volume is assumed to be at the average zone temperature unless you also specify an excess volume temperature.

Parameter | Value | Default
--- | --- | ---
{=} | {= | are | is} | –
excessVolume | “string” | –

###### Excess Volume Temperature

Syntax

  Excess Volume Temperature {=} excessVolumeTemperature

Summary

  Specifies the temperature of the excess volume. If omitted, the excess volume is treated as the same temperature as the main averaged temperature. If provided, you must also provide a weighting factor to use for RHO and RHO_CP temperature averaging schemes.

Parameter | Value | Default
--- | --- | ---
{=} | {= | are | is} | –
excessVolumeTemperature | real | Copied

###### Excess Volume Weight

Syntax

  Excess Volume Weight {=} excessVolumeWeight

Summary

  Specifies the weighting factor to use for the excess volume. For RHO averaging, this will be the density. For rhoCp averaging, this will be rho times Cp. For volume and ideal gas averaging this should not be provided.

Parameter | Value | Default
--- | --- | ---
{=} | {= | are | is} | –
excessVolumeWeight | real | 1

###### Initial Mixture Molecular Weight

Syntax

  Initial Mixture Molecular Weight {=} initMMW

Summary

  Specifies the mixture molecular weight of the initial gas present in the pressurization zone

Description

  Default is 28.97 g/mol for dry air. This should be specified in the appropriate units for the simulation. If no boundary conditions (e.g. venting or coupling to a gas transport region of the model) are applied to the pressurization zone then the value does not affect the results of the simulation.

Parameter | Value | Default
--- | --- | ---
{=} | {= | are | is} | –
initMMW | real | 28.97

###### Initial Pressure

Syntax

  Initial Pressure {=} initPressure

Summary

  Specifies the initial pressure in the specified pressure units.

Parameter | Value | Default
--- | --- | ---
{=} | {= | are | is} | –
initPressure | real | -1.0

###### Pressure Unit

Syntax

  Pressure Unit {=} pressureUnit

Summary

  This command specifies the units of pressure that is returned. Options are PA, ATM, and PSI (Default is Pa)

Parameter | Value | Default
--- | --- | ---
{=} | {= | are | is} | –
pressureUnit | string | Pa

###### Pressurization Source Blocks

Syntax

  Pressurization Source Blocks {=} sourceBlocks…

Summary

  A list of ChemEq blocks that provide the gas source(s) for this pressurization model.

Parameter | Value | Default
--- | --- | ---
{=} | {= | are | is} | –
sourceBlocks | string… | –

###### Pressurized Blocks

Syntax

  Pressurized Blocks {=} pressurizedBlocks…

Summary

  A list of blocks that the pressurization occurs in.

Parameter | Value | Default
--- | --- | ---
{=} | {= | are | is} | –
pressurizedBlocks | string… | –

###### Pressurized Bulk Nodes

Syntax

  Pressurized Bulk Nodes {=} pressurizedBulkNodes…

Summary

  A list of bulk nodes that the pressurization occurs in.

Parameter | Value | Default
--- | --- | ---
{=} | {= | are | is} | –
pressurizedBulkNodes | string… | –

###### Solver Name

Syntax

  Solver Name {=} solverName

Summary

  This command specifies the name of the ODE solver block to use for pressurization.

Parameter | Value | Default
--- | --- | ---
{=} | {= | are | is} | –
solverName | string | NONE

###### Temperature Averaging

Syntax

  Temperature Averaging {=} ventingModel

Summary

  This command specifies the temperature averaging model to use (VOLUME, IDEAL_GAS, RHO, or RHOCP)

Parameter | Value | Default
--- | --- | ---
{=} | {= | are | is} | –
ventingModel | string | IDEAL_GAS

###### Venting Model

Syntax

  Venting Model {=} ventingModel

Summary

  This command specifies the venting model to use (OPEN, CLOSED, or VENTED)

Parameter | Value | Default
--- | --- | ---
{=} | {= | are | is} | –
ventingModel | string | –

###### Venting Model Property

Syntax

  Venting Model Property propertyName {=} propertyModelAndParams…

Summary

  Define a material property associated with the venting model. Required if the venting model is VENTED. At a minimum a model for the VENTING_VOLUMETRIC_FLOW_RATE must be provided, and depending on the choice of that model additional properties may be required.

Parameter | Value | Default
--- | --- | ---
propertyName | string | –
{=} | {= | are | is} | –
propertyModelAndParams | string… | –