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. A functor is any of the following: a variable, a functor material property, a function, a post-processor, or a number.

    C++ Type:MooseFunctorName

    Unit:(no unit assumed)

    Controllable:No

    Description:Functor for the ratio of the total surface area with fins to the base surface area. A functor is any of the following: a variable, a functor material property, a function, a post-processor, or a number.

  • fin_area_fractionFunctor for the fraction of the total surface area corresponding to fins. A functor is any of the following: a variable, a functor material property, a function, a post-processor, or a number.

    C++ Type:MooseFunctorName

    Unit:(no unit assumed)

    Controllable:No

    Description:Functor for the fraction of the total surface area corresponding to fins. A functor is any of the following: a variable, a functor material property, a function, a post-processor, or a number.

  • fin_efficiencyFin efficiency functor. A functor is any of the following: a variable, a functor material property, a function, a post-processor, or a number.

    C++ Type:MooseFunctorName

    Unit:(no unit assumed)

    Controllable:No

    Description:Fin efficiency functor. A functor is any of the following: a variable, a functor material property, a function, a post-processor, or a number.

Required Parameters

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

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

    Unit:(no unit assumed)

    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>

    Unit:(no unit assumed)

    Controllable:No

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

  • 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

    Unit:(no unit assumed)

    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

    Unit:(no unit assumed)

    Controllable:No

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

  • execute_onALWAYSThe list of flag(s) indicating when this object should be executed. For a description of each flag, see https://mooseframework.inl.gov/source/interfaces/SetupInterface.html.

    Default:ALWAYS

    C++ Type:ExecFlagEnum

    Unit:(no unit assumed)

    Options:NONE, INITIAL, LINEAR, NONLINEAR_CONVERGENCE, NONLINEAR, POSTCHECK, TIMESTEP_END, TIMESTEP_BEGIN, MULTIAPP_FIXED_POINT_END, MULTIAPP_FIXED_POINT_BEGIN, FINAL, CUSTOM, ALWAYS

    Controllable:No

    Description:The list of flag(s) indicating when this object should be executed. For a description of each flag, see https://mooseframework.inl.gov/source/interfaces/SetupInterface.html.

  • fin_enhancement_factor_namefin_enhancement_factorName to give the fin enhancement factor functor material property. A functor is any of the following: a variable, a functor material property, a function, a post-processor, or a number.

    Default:fin_enhancement_factor

    C++ Type:MooseFunctorName

    Unit:(no unit assumed)

    Controllable:No

    Description:Name to give the fin enhancement factor functor material property. A functor is any of the following: a variable, a functor material property, a function, a post-processor, or a number.

  • 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

    Unit:(no unit assumed)

    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.

  • use_interpolated_stateFalseFor the old and older state use projected material properties interpolated at the quadrature points. To set up projection use the ProjectedStatefulMaterialStorageAction.

    Default:False

    C++ Type:bool

    Unit:(no unit assumed)

    Controllable:No

    Description:For the old and older state use projected material properties interpolated at the quadrature points. To set up projection use the ProjectedStatefulMaterialStorageAction.

Optional Parameters

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

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

    Unit:(no unit assumed)

    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

    Unit:(no unit assumed)

    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

    Unit:(no unit assumed)

    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

    Unit:(no unit assumed)

    Controllable:No

    Description:The seed for the master random number generator

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>

    Unit:(no unit assumed)

    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>

    Unit:(no unit assumed)

    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]