RayleighNumber

Postprocessor that computes the Rayleigh number for free flow with natural circulation

The Rayleigh number is computed as:

Ra=Δρl3gμk=ρβΔTl3gμkRa = \dfrac{\Delta \rho l^3 g}{\mu k} = \dfrac{\rho \beta \Delta T l^3 g}{\mu k}

where:

  • Δρ\Delta \rho is the density difference between the warm and cool region

  • ΔT\Delta T is the temperature difference between the warm and cool region

  • β\beta is the fluid expansion coefficient

  • ll is the size of the system in the direction of the temperature difference

  • gg is the magnitude of the gravity

  • μ\mu is the dynamic viscosity of the fluid

  • kk is the thermal diffusivity of the fluid

The density difference may be provided either directly or using the fluid expansion coefficient and the temperature difference. All quantities but gravity may be provided as postprocessors.

Input Parameters

  • cp_aveAverage value of the specific thermal capacity

    C++ Type:PostprocessorName

    Unit:(no unit assumed)

    Controllable:No

    Description:Average value of the specific thermal capacity

  • gravity_magnitudeGravity vector magnitude in the direction of interest

    C++ Type:double

    Unit:(no unit assumed)

    Controllable:No

    Description:Gravity vector magnitude in the direction of interest

  • k_aveAverage value of the thermal conductivity

    C++ Type:PostprocessorName

    Unit:(no unit assumed)

    Controllable:No

    Description:Average value of the thermal conductivity

  • lCharacteristic distance

    C++ Type:PostprocessorName

    Unit:(no unit assumed)

    Controllable:No

    Description:Characteristic distance

  • mu_aveAverage value of the dynamic viscosity

    C++ Type:PostprocessorName

    Unit:(no unit assumed)

    Controllable:No

    Description:Average value of the dynamic viscosity

  • rho_aveAverage density

    C++ Type:PostprocessorName

    Unit:(no unit assumed)

    Controllable:No

    Description:Average density

Required Parameters

  • T_coldMinimum temperature, or cold source temperature

    C++ Type:PostprocessorName

    Unit:(no unit assumed)

    Controllable:No

    Description:Minimum temperature, or cold source temperature

  • T_hotMaximum temperature, or hot source temperature

    C++ Type:PostprocessorName

    Unit:(no unit assumed)

    Controllable:No

    Description:Maximum temperature, or hot source temperature

  • betaAbsolute value of fluid volumetric expansion coefficient

    C++ Type:PostprocessorName

    Unit:(no unit assumed)

    Controllable:No

    Description:Absolute value of fluid volumetric expansion coefficient

  • execute_onTIMESTEP_ENDThe 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:TIMESTEP_END

    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, TRANSFER

    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.

  • 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.

  • rho_maxMaximum density

    C++ Type:PostprocessorName

    Unit:(no unit assumed)

    Controllable:No

    Description:Maximum density

  • rho_minMinimum density

    C++ Type:PostprocessorName

    Unit:(no unit assumed)

    Controllable:No

    Description:Minimum density

  • 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

  • allow_duplicate_execution_on_initialFalseIn the case where this UserObject is depended upon by an initial condition, allow it to be executed twice during the initial setup (once before the IC and again after mesh adaptivity (if applicable).

    Default:False

    C++ Type:bool

    Unit:(no unit assumed)

    Controllable:No

    Description:In the case where this UserObject is depended upon by an initial condition, allow it to be executed twice during the initial setup (once before the IC and again after mesh adaptivity (if applicable).

  • 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.

  • execution_order_group0Execution order groups are executed in increasing order (e.g., the lowest number is executed first). Note that negative group numbers may be used to execute groups before the default (0) group. Please refer to the user object documentation for ordering of user object execution within a group.

    Default:0

    C++ Type:int

    Unit:(no unit assumed)

    Controllable:No

    Description:Execution order groups are executed in increasing order (e.g., the lowest number is executed first). Note that negative group numbers may be used to execute groups before the default (0) group. Please refer to the user object documentation for ordering of user object execution within a group.

  • force_postauxFalseForces the UserObject to be executed in POSTAUX

    Default:False

    C++ Type:bool

    Unit:(no unit assumed)

    Controllable:No

    Description:Forces the UserObject to be executed in POSTAUX

  • force_preauxFalseForces the UserObject to be executed in PREAUX

    Default:False

    C++ Type:bool

    Unit:(no unit assumed)

    Controllable:No

    Description:Forces the UserObject to be executed in PREAUX

  • force_preicFalseForces the UserObject to be executed in PREIC during initial setup

    Default:False

    C++ Type:bool

    Unit:(no unit assumed)

    Controllable:No

    Description:Forces the UserObject to be executed in PREIC during initial setup

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

    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

  • 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

    Unit:(no unit assumed)

    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