# VanDerWaalsFreeEnergy

Free energy of a Van der Waals gas.

This material defines the Helmholtz free energy density of a Van der Waals gas.

(1)

where (a) and (b) are the Van der Waals coefficients, and !include GasFreeEnergyBase.md

## Input Parameters

• aVan der Waals coeefficient a (default mass_unit_conversion requires this to be in [eV*Ang^3])

C++ Type:double

Options:

Description:Van der Waals coeefficient a (default mass_unit_conversion requires this to be in [eV*Ang^3])

• cConcentration variable

C++ Type:std::vector

Options:

Description:Concentration variable

• bVan der Waals molecular exclusion volume b (default mass_unit_conversion requires this to be in [Ang^3])

C++ Type:double

Options:

Description:Van der Waals molecular exclusion volume b (default mass_unit_conversion requires this to be in [Ang^3])

• mGas atom mass (the default mass_unit_conversion requires this to be in [u])

C++ Type:double

Options:

Description:Gas atom mass (the default mass_unit_conversion requires this to be in [u])

• TTemperature

C++ Type:std::vector

Options:

Description:Temperature

• omegaLattice site volume (default mass_unit_conversion requires this to be in [Ang^3])

C++ Type:double

Options:

Description:Lattice site volume (default mass_unit_conversion requires this to be in [Ang^3])

### Required Parameters

• computeTrueWhen false, MOOSE will not call compute methods on this material. The user must call computeProperties() after retrieving the Material via MaterialPropertyInterface::getMaterial(). Non-computed Materials are not sorted for dependencies.

Default:True

C++ Type:bool

Options:

Description:When false, MOOSE will not call compute methods on this material. The user must call computeProperties() after retrieving the Material via MaterialPropertyInterface::getMaterial(). Non-computed Materials are not sorted for dependencies.

• log_tol0.1The logarithm in the free energy is evaluated using a Taylor expansion below this value. This allows formulating free energies for systems where the molecular volume is smaller than the exclusion volume b.

Default:0.1

C++ Type:double

Options:

Description:The logarithm in the free energy is evaluated using a Taylor expansion below this value. This allows formulating free energies for systems where the molecular volume is smaller than the exclusion volume b.

• f_nameFBase name of the free energy function (used to name the material properties)

Default:F

C++ Type:std::string

Options:

Description:Base name of the free energy function (used to name the material properties)

• derivative_order3Maximum order of derivatives taken

Default:3

C++ Type:unsigned int

Options:

Description:Maximum order of derivatives taken

• boundaryThe list of boundary IDs from the mesh where this boundary condition applies

C++ Type:std::vector

Options:

Description:The list of boundary IDs from the mesh where this boundary condition applies

• blockThe list of block ids (SubdomainID) that this object will be applied

C++ Type:std::vector

Options:

Description:The list of block ids (SubdomainID) that this object will be applied

### Optional Parameters

• fail_on_evalerrorFalseFail fatally if a function evaluation returns an error code (otherwise just pass on NaN)

Default:False

C++ Type:bool

Options:

Description:Fail fatally if a function evaluation returns an error code (otherwise just pass on NaN)

• enableTrueSet the enabled status of the MooseObject.

Default:True

C++ Type:bool

Options:

Description:Set the enabled status of the MooseObject.

• use_displaced_meshFalseWhether or not this object should use the displaced mesh for computation. Note that in the case this is true but no displacements are provided in the Mesh block the undisplaced mesh will still be used.

Default:False

C++ Type:bool

Options:

Description:Whether or not this object should use the displaced mesh for computation. Note that in the case this is true but no displacements are provided in the Mesh block the undisplaced mesh will still be used.

• enable_jitTrueEnable just-in-time compilation of function expressions for faster evaluation

Default:True

C++ Type:bool

Options:

Description:Enable just-in-time compilation of function expressions for faster evaluation

• control_tagsAdds user-defined labels for accessing object parameters via control logic.

C++ Type:std::vector

Options:

Description:Adds user-defined labels for accessing object parameters via control logic.

• seed0The seed for the master random number generator

Default:0

C++ Type:unsigned int

Options:

Description:The seed for the master random number generator

• enable_auto_optimizeTrueEnable automatic immediate optimization of derivatives

Default:True

C++ Type:bool

Options:

Description:Enable automatic immediate optimization of derivatives

• disable_fpoptimizerFalseDisable the function parser algebraic optimizer

Default:False

C++ Type:bool

Options:

Description:Disable the function parser algebraic optimizer

• enable_ad_cacheTrueEnable cacheing of function derivatives for faster startup time

Default:True

C++ Type:bool

Options:

Description:Enable cacheing of function derivatives for faster startup time

• implicitTrueDetermines whether this object is calculated using an implicit or explicit form

Default:True

C++ Type:bool

Options:

Description:Determines whether this object is calculated using an implicit or explicit form

• constant_onNONEWhen ELEMENT, MOOSE will only call computeQpProperties() for the 0th quadrature point, and then copy that value to the other qps.When SUBDOMAIN, MOOSE will only call computeSubdomainProperties() for the 0th quadrature point, and then copy that value to the other qps. Evaluations on element qps will be skipped

Default:NONE

C++ Type:MooseEnum

Options:NONE ELEMENT SUBDOMAIN

Description:When ELEMENT, MOOSE will only call computeQpProperties() for the 0th quadrature point, and then copy that value to the other qps.When SUBDOMAIN, MOOSE will only call computeSubdomainProperties() for the 0th quadrature point, and then copy that value to the other qps. Evaluations on element qps will be skipped

• h4.13567e-15Planck constant - units need to be consistent with the units of omega (default in [eV*s])

Default:4.13567e-15

C++ Type:double

Options:

Description:Planck constant - units need to be consistent with the units of omega (default in [eV*s])

• mass_unit_conversion1.03643e-28Conversion factor to get the gas atom mass in [eV*s^2/Ang^2] (defaults to [eV*s^2/(Ang^2*u)])

Default:1.03643e-28

C++ Type:double

Options:

Description:Conversion factor to get the gas atom mass in [eV*s^2/Ang^2] (defaults to [eV*s^2/(Ang^2*u)])

• kB8.61733e-05Boltzmann constant (default in [eV/K])

Default:8.61733e-05

C++ Type:double

Options:

Description:Boltzmann constant (default in [eV/K])

### Units Parameters

• output_propertiesList of material properties, from this material, to output (outputs must also be defined to an output type)

C++ Type:std::vector

Options:

Description:List of material properties, from this material, to output (outputs must also be defined to an output type)

• outputsnone Vector of output names were you would like to restrict the output of variables(s) associated with this object

Default:none

C++ Type:std::vector

Options:

Description:Vector of output names were you would like to restrict the output of variables(s) associated with this object