Fluent Overview Ahmadi/Nazridoust ME 437/537/637.

Fluent Fluent OverviewOverview

Ahmadi/NazridoustME 437/537/637



Solution ParametersSolution Parameters Choosing the SolverChoosing the Solver Discretization SchemesDiscretization Schemes

InitializationInitialization ConvergenceConvergence

Monitoring ConvergenceMonitoring Convergence StabilityStability

Setting Under-relaxationSetting Under-relaxation Setting Courant numberSetting Courant number

Accelerating ConvergenceAccelerating Convergence AccuracyAccuracy

Grid IndependenceGrid Independence AdaptationAdaptation

Set Solution Parameters

Initialize

Enable Solution Monitors

Calculate a Solution

Modify the Solution Parameters or the MeshConverged?

No

No

Yes

Yes

Accurate?

Stop



Import (scale) the mesh fileImport (scale) the mesh file Select physical modelsSelect physical models Define material propertiesDefine material properties Prescribe operating Prescribe operating

conditionsconditions Prescribe boundary Prescribe boundary

conditionsconditions Provide an initial solutionProvide an initial solution Set solver controlsSet solver controls Set up convergence Set up convergence

monitorsmonitors Compute and monitor Compute and monitor

solutionsolution

Menu is laid out such that order of operation is Menu is laid out such that order of operation is generally left to right.generally left to right.



Mouse button functionality depends on Mouse button functionality depends on solver and can be configured in the solver and can be configured in the solversolver

Display MenuDisplay Menu Mouse Buttons... Mouse Buttons... Default Settings:Default Settings:

2D Solver2D Solver Left button translates (dolly)Left button translates (dolly) Middle button zoomsMiddle button zooms Right button selects/probesRight button selects/probes

3D Solver3D Solver Left button rotates about 2-axesLeft button rotates about 2-axes Middle button zoomsMiddle button zooms Right button selects/probesRight button selects/probes



Components are defined in Components are defined in preprocessorpreprocessor Cell = control volume into which Cell = control volume into which

domain is broken updomain is broken up computational domain is defined by computational domain is defined by

mesh that represents the fluid and mesh that represents the fluid and solid regions of interest.solid regions of interest.

Face = boundary of a cellFace = boundary of a cell Edge = boundary of a faceEdge = boundary of a face Node = grid pointNode = grid point Zone = group of nodes, faces, and/or Zone = group of nodes, faces, and/or

cellscells Boundary data assigned to face Boundary data assigned to face

zones.zones. Material data and source terms Material data and source terms

assigned to cell zones.assigned to cell zones.

facecell

node

edge

3D mesh

cell center

2D mesh

node

face

cell



How to…How to… File Menu File Menu Read Read Case Case



How to…How to… Grid Menu Grid Menu

CheckCheck Grid Menu Grid Menu

ScaleScale Grid Menu Grid Menu

TranslateTranslate

Fluent assumes that all physical dimensions are initially in Fluent assumes that all physical dimensions are initially in metersmeters.. The default unit system in Fluent is Metric (SI) units.The default unit system in Fluent is Metric (SI) units.



How to…How to… Display Menu Display Menu Grid Grid



How to…How to… Define Menu Define Menu Models Models Solver Solver

Define Menu Define Menu Models Models Viscous Viscous



How to…How to… Define Menu Define Menu Materials Materials Fluent Database Fluent Database

Physical models may Physical models may require additional material require additional material properties need to be properties need to be defined.defined.

Single-Phase, Single Single-Phase, Single Species FlowsSpecies Flows Define fluid/solid Define fluid/solid

propertiesproperties Real gas model Real gas model Multiple Phase Flows Multiple Phase Flows

(Single Species)(Single Species) Define properties for Define properties for

all fluids and solids.all fluids and solids.

Multiple Species Multiple Species (Single Phase) Flows(Single Phase) Flows

Mixture Material concept Mixture Material concept employedemployed

Mixture properties Mixture properties (composition (composition dependent) dependent) defined separately defined separately from constituent’s from constituent’s properties.properties.

Component properties Component properties must be defined.must be defined.



How to…How to… Define Menu Define Menu

Materials Materials Fluent Fluent DatabaseDatabase



To formulate a problem that results in a To formulate a problem that results in a uniqueunique solution, the relevant variables at solution, the relevant variables at the domain boundaries must be defined.the domain boundaries must be defined.

Specifying velocity, temperature and Specifying velocity, temperature and pressure or fluxes of mass, momentum, pressure or fluxes of mass, momentum, energy.energy.

Defining boundary conditions involves:Defining boundary conditions involves:

i.i. identifying the location of the identifying the location of the boundaries (e.g., inlets, walls, boundaries (e.g., inlets, walls, symmetry)symmetry)

ii.ii. supplying information at the boundariessupplying information at the boundaries



How to… How to… Define Menu Define Menu Boundary Conditions Boundary Conditions Select ZonesSelect Zones

Boundary Condition Types of Boundary Condition Types of External FacesExternal Faces General: Pressure inlet, Pressure outletGeneral: Pressure inlet, Pressure outlet Incompressible: Velocity inlet, OutflowIncompressible: Velocity inlet, Outflow Compressible flows: Mass flow inlet, Pressure far-Compressible flows: Mass flow inlet, Pressure far-

fieldfield Special: Inlet vent, outlet vent, intake fan, exhaust Special: Inlet vent, outlet vent, intake fan, exhaust

fanfan Other: Wall, Symmetry, Periodic, AxisOther: Wall, Symmetry, Periodic, Axis

Boundary Condition Types of Boundary Condition Types of Cell ‘Boundaries’Cell ‘Boundaries’ Fluid and SolidFluid and Solid

Boundary Condition Types of Boundary Condition Types of Double-Sided Face Double-Sided Face ‘Boundaries’‘Boundaries’ Fan, Interior, Porous Jump, Radiator, WallsFan, Interior, Porous Jump, Radiator, Walls



How to… How to… Define Menu Define Menu Boundary Boundary Conditions Conditions Select Select ZonesZones



How to…How to… Solve Menu Solve Menu Initialize Initialize

Initialize Initialize



How to…How to… Solve Menu Solve Menu Monitors Monitors

Residuals Residuals

The convergence of The convergence of solution can also be solution can also be changedchanged



How to…How to… Solve Menu Solve Menu Iterate Iterate

IterateIterate



How to…How to… Display Menu Display Menu

ContoursContours Display Menu Display Menu Vectors Vectors



Flow in a ChannelFlow in a Channel Steady StateSteady State Inlet Velocity is knownInlet Velocity is known Outlet is open to atmospheric pressureOutlet is open to atmospheric pressure No Slip on all wallsNo Slip on all walls Fluid is WaterFluid is Water Desired Grid Resolution is 1500 Hexahedral Cells Desired Grid Resolution is 1500 Hexahedral Cells

60cm

15cm

x-Velocity = 0.85 m/sy-Velocity = 0.00 m/s Outflow

Fluent Overview Ahmadi/Nazridoust ME 437/537/637.

Documents

Transcript of Fluent Overview Ahmadi/Nazridoust ME 437/537/637.