- gravityGravitational acceleration vector.C++ Type:libMesh::VectorValue<double> Unit:(no unit assumed) Controllable:No Description:Gravitational acceleration vector. 
- momentum_componentThe component of the momentum equation that this kernel applies to.C++ Type:MooseEnum Controllable:No Description:The component of the momentum equation that this kernel applies to. 
- reference_rhoThe value for the reference densityC++ Type:double Unit:(no unit assumed) Controllable:No Description:The value for the reference density 
- rhoThe value for the density. A functor is any of the following: a variable, a functor material property, a function, a postprocessor or a number.C++ Type:MooseFunctorName Unit:(no unit assumed) Controllable:No Description:The value for the density. A functor is any of the following: a variable, a functor material property, a function, a postprocessor or a number. 
- variableThe name of the variable whose linear system this object contributes toC++ Type:LinearVariableName Unit:(no unit assumed) Controllable:No Description:The name of the variable whose linear system this object contributes to 
LinearFVMomentumBuoyancy
This kernel adds the contributions of the buoyancy force due to density differences through a force/source term to the right hand side of the momentum equation system for the finite volume SIMPLE segregated solver SIMPLE.
This term is described by  present in the momentum conservation equation when describing an incompressible fluid, where  is the reference density, and  is the gravity vector. The buoyancy model accepts arbitrary temperature-dependent functions for density. The LinearFVMomentumBuoyancy kernel allows for modeling natural convection.
This term deals only with the force due to the variation in density , with the fluid density being . Thus, with no extra added terms to the conventional incompressible Navier Stokes equations, the system will solve for the total pressure minus the hydrostatic pressure.
For stability purposes, the value of is recommended be set to the midpoint of the estimated maximum and minimum temperature values in the simulation.
For natural convection simulations, it is advisable to compute relevant dimensionless numbers such as the Rayleigh number or the Richardson number to decide on the need for turbulence models, mesh refinement and stability considerations.
Input Parameters
- blockThe list of blocks (ids or names) that this object will be appliedC++ Type:std::vector<SubdomainName> Controllable:No Description:The list of blocks (ids or names) that this object will be applied 
- matrix_onlyFalseWhether this object is only doing assembly to matrices (no vectors)Default:False C++ Type:bool Controllable:No Description:Whether this object is only doing assembly to matrices (no vectors) 
Optional Parameters
- absolute_value_vector_tagsThe tags for the vectors this residual object should fill with the absolute value of the residual contributionC++ Type:std::vector<TagName> Controllable:No Description:The tags for the vectors this residual object should fill with the absolute value of the residual contribution 
- extra_matrix_tagsThe extra tags for the matrices this Kernel should fillC++ Type:std::vector<TagName> Controllable:No Description:The extra tags for the matrices this Kernel should fill 
- extra_vector_tagsThe extra tags for the vectors this Kernel should fillC++ Type:std::vector<TagName> Controllable:No Description:The extra tags for the vectors this Kernel should fill 
- matrix_tagssystemThe tag for the matrices this Kernel should fillDefault:system C++ Type:MultiMooseEnum Controllable:No Description:The tag for the matrices this Kernel should fill 
- vector_tagsrhsThe tag for the vectors this Kernel should fillDefault:rhs C++ Type:MultiMooseEnum Controllable:No Description:The tag for the vectors this Kernel should fill 
Contribution To Tagged Field Data 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 formDefault: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 generatorDefault: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
- ghost_layers1The number of layers of elements to ghost.Default:1 C++ Type:unsigned short Controllable:No Description:The number of layers of elements to ghost. 
- use_point_neighborsFalseWhether to use point neighbors, which introduces additional ghosting to that used for simple face neighbors.Default:False C++ Type:bool Controllable:No Description:Whether to use point neighbors, which introduces additional ghosting to that used for simple face neighbors.