FinEnhancementFactorFunctorMaterial

This functor material computes the enhancement factor for a convective heat transfer condition due to extended surfaces such as fins.

Formulation

Consider the convective heat transfer rate at a surface with area without the addition of any fins:

where

  • is the heat transfer coefficient,

  • is the surface temperature, and

  • is the fluid temperature.

The addition of extended surfaces such as fins to the surface enhances this heat transfer rate by a factor :

(1)

The fin efficiency characterizes the performance of a single fin and is defined as the ratio of the heat transfer rate through the fin to the theoretical maximum heat transfer rate through the fin (Incropera et al., 2002):

where is the surface area of the fin.

The total surface efficiency characterizes the performance of an array of fins on a surface, not just a single fin, as does, and is defined as the ratio of the total heat transfer rate of the entire surface to the theoretical maximum heat transfer rate (Incropera et al., 2002):

(2)(3)

Combining Eq. (1), Eq. (2), and Eq. (3) gives the definition of the enhancement factor:

where is the total surface area, including fins. The total efficiency is computed from the fin efficiency and the fin area ratio (Incropera et al., 2002):

where is the surface area of all fins on the surface.

Usage

This functor material creates a functor material property for the enhancement factor with the name given by the parameter "fin_enhancement_factor_name".

The quantities , , and are provided by the functor parameters "fin_efficiency", "fin_area_fraction", and "area_increase_factor", respectively.

Input Parameters

  • area_increase_factorFunctor for the ratio of the total surface area with fins to the base surface area

    C++ Type:MooseFunctorName

    Controllable:No

    Description:Functor for the ratio of the total surface area with fins to the base surface area

  • fin_area_fractionFunctor for the fraction of the total surface area corresponding to fins

    C++ Type:MooseFunctorName

    Controllable:No

    Description:Functor for the fraction of the total surface area corresponding to fins

  • fin_efficiencyFin efficiency functor

    C++ Type:MooseFunctorName

    Controllable:No

    Description:Fin efficiency functor

Required Parameters

  • blockThe list of blocks (ids or names) that this object will be applied

    C++ Type:std::vector<SubdomainName>

    Controllable:No

    Description:The list of blocks (ids or names) that this object will be applied

  • boundaryThe list of boundaries (ids or names) from the mesh where this object applies

    C++ Type:std::vector<BoundaryName>

    Controllable:No

    Description:The list of boundaries (ids or names) from the mesh where this object applies

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

    Default:True

    C++ Type:bool

    Controllable:No

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

  • 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 computeQpProperties() 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

    Controllable:No

    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 computeQpProperties() for the 0th quadrature point, and then copy that value to the other qps. Evaluations on element qps will be skipped

  • declare_suffixAn optional suffix parameter that can be appended to any declared properties. The suffix will be prepended with a '_' character.

    C++ Type:MaterialPropertyName

    Controllable:No

    Description:An optional suffix parameter that can be appended to any declared properties. The suffix will be prepended with a '_' character.

  • fin_enhancement_factor_namefin_enhancement_factorName to give the fin enhancement factor functor material property

    Default:fin_enhancement_factor

    C++ Type:MooseFunctorName

    Controllable:No

    Description:Name to give the fin enhancement factor functor material property

  • prop_getter_suffixAn optional suffix parameter that can be appended to any attempt to retrieve/get material properties. The suffix will be prepended with a '_' character.

    C++ Type:MaterialPropertyName

    Controllable:No

    Description:An optional suffix parameter that can be appended to any attempt to retrieve/get material properties. The suffix will be prepended with a '_' character.

Optional Parameters

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

    C++ Type:std::vector<std::string>

    Controllable:No

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

  • enableTrueSet the enabled status of the MooseObject.

    Default:True

    C++ Type:bool

    Controllable:Yes

    Description:Set the enabled status of the MooseObject.

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

    Default:True

    C++ Type:bool

    Controllable:No

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

  • seed0The seed for the master random number generator

    Default:0

    C++ Type:unsigned int

    Controllable:No

    Description:The seed for the master random number generator

  • 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

    Controllable:No

    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.

Advanced Parameters

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

    C++ Type:std::vector<std::string>

    Controllable:No

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

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

    Default:none

    C++ Type:std::vector<OutputName>

    Controllable:No

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

Outputs Parameters

References

  1. Frank P. Incropera, David P. DeWitt, Theodore L. Bergman, Adrienne S. Lavine, and others. Fundamentals of Heat and Mass Transfer. Wiley New York, sixth edition, 2002.[BibTeX]