Fluent Tutorial

Fluent tutorials

Gabriel W¸ecel ecel 30th March 2009

Contents 0.1

0.2

Air heater . . . . . . . . . . . . . . . . . 0.1.1 Building geometry . . . . . . . . 0.1. 0.1.22 Sett Settin ingg boun bounda darry cond condit itio ion n types pes 0.1.3 Setti tting Fluent parameters . . . . 0.1.4 Performing calculations . . . . . 0.1.5 Final remarks . . . . . . . . . . . Cyclone. . . . . . . . . . . . . . . . . . . 0.2.1 Building geometry . . . . . . . . 0.2. 0.2.22 Sett Settin ingg boun bounda darry cond condit itio ion n types pes 0.2.3 Meshing geometry . . . . . . . . 0.2.4 Setti tting Fluent parameters . . . . 0.2.5 Performing calculatio tions . . . . .

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0.1

Air heater

This example shows how to simplify 3D geometry of the real object and perform calculation in 2D space. Air heater geometry is given in Figure 1. The air stream flows from left to the right. There are only two opening in the heater, inlet (left ) and outlet (right ). The other sides ( front, back, top, bottom ) are insulated walls. Inside the heater 3 cylindrical pipes are positioned perpendicular to the flow. Data of the operation of the heater are given in Table 1. The flow patern in such configuration of the heater in any cross section (aligned with flow direction) is almost the same. The width of the heater is high enough to neglect influence of the side walls ( front  and back ) on the flow in the middle part of the heater. Hence we can simulate flow in the heater with good accuracy assuming 2D geometry (see the heater cross section in the Figure 2, we do not  utilize symmetry of the cross section geometry since we want later to analyze different cylinder alignments). Even for simplified geometry flow over cylinders

emerge to be complex, with stagnation zones and revers flow close to the cylinders. That feature require proper treatment of the mesh. First of all it needs to be symmetric as the flow is symmetric. The best is to try generate fully structured mesh and if possible with cells edges aligned with the direction of  the flow. This is not possible in all area of the flow, but at least at the cylinder boundaries cells alignment should follow flow direction.

heaters

inlet

outflow

Figure 1: Air heater.

air flow air inlet temperature thermal input at each heater walls thermal condition

5 300 1.6 0

m/s K  kW  kW  (isolation)

Table 1: Air heater set up parameter

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  m   0  4  .   0

heaters m

insulated walls

0.2 m

.2 0

0.1 m 0.1 m 1m

inlet

outflow

Figure 2: Air heater cross section - dimensions.

0.1.1

Building geometry

As already mentioned we require structured mesh made of  Quad type elements. In order to use Quad elements we need earlier to plan how to divide geometry in topological faces which later are easy to mesh. Figure 3 shows proposition of  topological division of the air heater geometry. One can recognize that all faces posses 4 edges what allows to mesh them easily with Quad elements.

Figure 3: Air heater topological division of the geometry. See below listing of the geometry creation procedure. Geometry Edge Create Edge Arc Select method: Radius, Start Angle, End Angle Enter Radius = 0.02, Start Angle = -45, End Angle = 45 Press Apply →

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Enter Radius = 0.02, Start Angle = 45, End Angle = 135 Press Apply Enter Radius = 0.02, Start Angle = 135, End Angle = 225 Press Apply

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Enter Radius = 0.02, Start Angle = 225, End Angle = 315 Press Apply Geometry Vertex Create Vertex Enter X = 0.05, Y = -0.05, Z = 0 Press Apply →

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Enter X = 0.05, Y = 0.05, Z = 0 Press Apply Enter X = -0.05, Y = 0.05, Z = 0 Press Apply Enter X = -0.05, Y = -0.05, Z = 0 Press Apply create edges around tube

Geometry Edge Create Edge Straight Select with mouse (holding Shift button) created Vertices (only 2 at the same time) Press Apply →

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Repeat operation (8 times) in order to get effect shown in Figure 4.

Figure 4: Edges around the tube.

create faces around tube

Geometry Face Form Face Wireframe Select with mouse (holding Shift button) created Edges (only 4 at the same time) Press Apply →

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Repeat operation (4 times) in order to get effect shown in Figure 5.

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Face 1 4

2

e

e

a

a

c c F

F

Face 3

Figure 5: Faces around the tube.

mesh faces around tube, first set distribution of the nodes on the edges

Mesh Edge Mesh Edges Select with mouse (holding Shift button) edges creating tube Deselect Grading Select Spacing and enter Interval size = 0.001 Select Option Mesh Press Apply →

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set distribution of the nodes on the edges radially connected with tube Select with mouse (holding Shift button) radial edges Select Grading Select Type First Length and enter Length = 0.001 Select Spacing and enter Interval count = 20 Select Option Mesh Press Apply mesh faces around tube

Mesh Face Mesh Faces Select with mouse (holding Shift button) all 4 faces Select Scheme Select Elements Quad Select Type Map Press Apply →

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The mesh generated should have similar form of that shown in Figure 6, however number of elements is different. make 2 copies of mesh around the tubes

Geometry Face Move/Copy/Align Select with mouse all faces Select Copy and enter 2 (this is number of copies) Select Operation Translate Enter X = 0.1, Y = 0, Z = 0 →

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Figure 6: Mesh around the tube.

Press Apply The effect of operation is shown in Figure 7, ( number of elements is different ).

Figure 7: Copied mesh around the tubes. Coping of the faces in the way presented above result in double Edges lying at the same position between copied meshes. If we did not set them as interfaces Fluent will treat them as walls ( no flow between these part of mesh ) . Simple solution to this problem is connecting  this edges. Geometry Edge Connect Edges Select with mouse all double faces ( lying at the same position ) Select Real Press Apply →

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As the result the double edges will be connected and one of them be deleted. Remaining part of the mesh is generated by simply creating rectangular faces. Since procedure is very simple only picture showing consequent steps is given in Figure 8.

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Figure 8: Steps of creating air heater geometry.

0.1.2

Setting boundary condition types

The last step in Gambit is setting boundary condition types. Zones Specify Boundary Types Check (Add) Enter, Name: inlet Select Type VELOCITY INLET Pick Entity : Edges, edge representing inlet to the cyclone, see Figure 2 press Apply →

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Zones Specify Boundary Types Check (Add) Enter, Name: outlet Select Type OUTFLOW Pick Entity : Edges, edge representing outlet from the cyclone, see Figure 2 press Apply →

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Zones Specify Boundary Types Check (Add) Enter, Name: sides Select Type WALL Pick Entity : Edges, edges creating top and bottom wall of the heater press Apply →

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Zones Specify Boundary Types Check (Add) →

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Enter, Name: heater 01 Select Type WALL Pick Entity : Edges, edge creating first pipe of the heater press Apply →

Zones Specify Boundary Types Check (Add) Enter, Name: heater 02 Select Type WALL Pick Entity : Edges, edge creating second pipe of the heater press Apply →

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Zones Specify Boundary Types Check (Add) Enter, Name: heater 03 Select Type WALL Pick Entity : Edges, edge creating third pipe of the heater press Apply →

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export generated mesh into the file

File Export Mesh... Enter File Name: heater.msh Check (Export 2d Mesh) press Apply →

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0.1.3

Setting Fluent parameters

After reading mesh generated with Gambit we have to define all the models, material properties, boundary conditions and solver parameters required to simulate operation of heater. Most of the parameter in Fluent can be left as default. The procedure listed below shows mainly these settings which needs to be changed. Read mesh file ( mesh files have extension  msh) ˙ created in previous section. File Read Case... Define solver settings as default. Define Models Solver... Set turbulence modell Define Models Viscous... Select k  Standard turbulence model with option Standard Wall Function Define material properties Define Materials... Check material properties for air Enter Density (kg/m3) equal to 1.225 Enter Cp (j/kgK) equal to 1006.43 →

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Enter Thermal Conductivity (W/mK) equal to 0.0242 Enter Viscosity (kg/ms) equal to 1.7894e-5 Confirm changes pressing Change Create Close Material panel pressing Close Define boundary condition Define Boundary Conditions... Select Zone inlet, press Set Enter Velocity Magnitude (m/s) equal to 5 Enter Temperature (K) equal to 300 Select Turbulence Specification Method Intensity and Hydraulic Diameter Enter Turbulence Intensity (%) equal to 10 Enter Hydraulic Diameter (m) equal to 0.4 Accept settings pressing OK Select Zone heater 01, press Set From Thermal tab for Thermal Conditions select Heat Flux Enter Heat Flux (W/m2) equal to 16000 Accept settings pressing OK Press Copy from Boundary Condition panel Under From Zone select heater 01 Under To Zone select heater 02, heater 03 Press Copy Accept selection pressing OK Close Copy BCs panel pressing Close Close Boundary Conditions panel pressing Close →

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set up solver parameters

Solve

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Controls

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Solution...

assume all default settings

Initialize solution Solve Initialize Initialize... Press Init and close Solution Initialization panel Set solution monitoring option Solve Monitors Residual... Under Option select Plot For Residual continuity Convergence Criterion enter value equal to 10e-9 Accept settings pressing OK save Fluent settings parameter in case file ( case files have extension  .cas) File Write Case..., enter file name and accept settings pressing OK →

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0.1.4

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Performing calculations

Herewith we assume that Fluent is open and case file with heater is read. Type in Fluent command window it 100, (this command executes 100 iterations) Observe in Fluent result window residuals of the solved equations

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Post processing

All calculated variable can be displayed in the Fluent result window in the form of colored field. Additionally profiles of these variables can be created at arbitral position inside computational domain. The result window can be zoomed in and out in order to observe particular regions of the flow. Displayed variable scale can be adjusted to arbitral ranges. Solution variables can be displayed as follow, Select Display Contours... From Option select Filled →

static pressure will be displayed 

From Contours of , select Pressure... Press Display

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Static Pressure

Repeating procedure above one can display all solution variables. Creating profile line for extracting data

Herewith we will create line cutting the cross section of the domain at the position 0.5 m from the inlet to the heater. Line will be aligned vertically and perpendicular to the flow direction. Surface Line/Rake... From Type select Rake, advantage of using  Rake instead of  Line is that we prede fine number of points at which values are plotted or printed, in case of using Line number of points for dense meshes can be large, additionally  Line extract values  from the closes volume cell center, when  Rake interpolate values from closes vol→

ume cells and calculate it for position at which point of a rake is placed.

For Number of Point enter required value, we suggest at least 20, but that strongly  depend on the problem solved, variable printed and position of the Rake From Points enter, x0(m) = 0.1, x1(m) = 0.5 y0(m) = 0, y1(m) = 0.2 For New Surface Name enter desired name of the rake and press Create Close Line/Rake Surface panel pressing Close Created Rake can be used from Plot XY Plot... panel in order to plot, print or write to a file solution variables placed on the defined by rake positions. →

0.1.5

Final remarks

Experienced user can realize that presented here case is not trivial one. First of all turbulence model used here is not always suitable for such a flows since Reynolds number is at the very low level of 11 000. There is completely neglected

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discussion of the near wall treatment and simply standard wall approach is utilized. However main purpose of this tutorial is to show how to relatively easy create structured mesh for the geometry which automatic mesh generator are not able to handle such meshes. One can try to build geometry with different heater alignments and observe how that influence, the flow, pressure drop, and temperature profile at the outlet of  the heater.

0.2

Cyclone.

In many industrial processes emerge a need of cleaning gases from dispersed inert particles suspended within gas (eg. removal of flying ash from flue gases in industrial coal fired boilers). Easiest and most commonly used method of  separation takes advantage of gravitation forces. Device which work on this basis is a cyclone. With this tutorial we build simple cyclone geometry, mesh it, and run Fluent simulations. Instead of flue gases we will use air stream polluted with ash. Data for boundary conditions are given in Table 2. air flow air flow temperature ash mass flux min. particle diameter max. particle diameter mean particle diameter spread parameter ash density

0.27 50 0.001 1 300 150 2.8 2100

m3 /s 0 C  kg/s µm µm µm n

kg/m3

Table 2: Cyclone running parameter Figure 9 shows cyclone dimensions. Geometry of the cyclone is build in Gambit using volume primitives. Figure 10 shows all volumes used to build the cyclone which are connected using boolean operations.

0.2.1

Building geometry

Procedure of building the cyclone geometry is very simple. First we create and move in the right position volume primitives presented in Figure 10. Next boolean summation and subtraction is used to unite all primitives in order to create one volume representing a cyclone. See below listing of the geometry creation procedure. Listing shows order of operations to be carried out in Gambit. Geometry Volume Create Volume Cylinder Enter Height = 0.5, Radius 1 = 0.3, Radius 2 = 0.3 press Apply →

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0.6 m     m

0.2 m

        2

 .      0 

    m  .      0 

    m

    m

        8 

        5 

 .      0 

        2

 .      0 

  7   0.

m

0.2 m     m  .0 1

0.2 m     m         5          0 

 .      0 

    m         2

0.4 m

 .      0 

Figure 9: Cyclone dimensions.

Geometry Volume Create Volume Frustum Enter Height = 1.0, Radius 1 = 0.3, Radius 2 = 0.3, Radius 3 = 0.1 press Apply →

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Geometry Volume Move/Copy/Align Select with the mouse created frustum: Pick Volume 2 Check Move, Translate Enter X = 0, Y = 0, Z = 0.5 press Apply →

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Geometry Volume Create Volume Cylinder Enter Height = 0.05, Radius 1 = 0.1, Radius 2 = 0.1 →

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0.6 m

    m  .      0 

        2

    m  .      0 

        5 

0.2 m

  7 0.

m

0.6 m 0.2 m

    m  .      0 

    m  .0

        8 

1

0.2 m

0.2 m

    m         5          0 

 .      0 

0.4 m

    m  .      0 

        2

Figure 10: Volume primitives for Cyclone.

press Apply Geometry Volume Move/Copy/Align Select with the mouse created cylinder: Pick Volume 3 Check Move, Translate Enter X = 0, Y = 0, Z = 1.5 press Apply →

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Geometry Volume Create Volume Cylinder Enter Height = 0.15, Radius 1 = 0.2, Radius 2 = 0.2 press Apply →

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Geometry Volume Move/Copy/Align Select with the mouse created cylinder: Pick Volume 4 →

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Check Move, Translate Enter X = 0, Y = 0, Z = 1.55 press Apply Geometry Volume Create Volume Cylinder Enter: Height = 0.8, Radius 1 = 0.1, Radius 2 = 0.1 press Apply →

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Geometry Volume Move/Copy/Align Select with the mouse created cylinder: Pick Volume 5 Check Move, Translate Enter X = 0, Y = 0, Z = -0.2 press Apply →

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Geometry Volume Create Volume Brick Enter Width = 0.2, Depth = 0.7, Height = 0.2 press Apply →

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Geometry Volume Move/Copy/Align Select with the mouse created cylinder: Pick Volume 6 Check Move, Translate Enter X = 0.2, Y = 0.35, Z = 0.1 press Apply →

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Geometry Volume Boolean Operations Unite Select with the mouse all the volumes except last created (Volume 6): Pick Volume 1,Volume 2,Volume 3,Volume 4,Volume 5 press Apply →

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Geometry Volume Boolean Operations Subtract Select with the mouse the volumes which is result of last operation: Volume Volume 1 Select with the mouse remaining volume: Subtract Volume Volume 5 Check Retain under Subtract Volume press Apply →

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Geometry Face Connect/Disconnect Faces Connect Select with the mouse faces aligned between volumes, only this which are at the cover of small cylinder, see figure 11. This operation is needed to force continuum between volumes. It results in deleting one of the face which are aligned at the same position. After operation two volumes are linked by one face forcing later the same mesh to be generated for both volumes at that face. Not connected faces will be by default treated as wall. In our case, side cylinder face of the Volume 5 will be a wall. press Apply after making selection →

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Figure 11: Faces to be selected for Face Connect oparation.

0.2.2

Setting boundary condition types

In order to indicate inlet and outlet of the cyclone we need to specify boundary condition types in Gambit. Additionally ash hopper has to be marked as separate wall, this is required for dispersed phase modelling. See listing of boundary types setting below. Zones Specify Boundary Types Check (Add) Enter, Name: in Select Type VELOCITY INLET Pick Entity : Faces, face representing inlet to the cyclone, see Figure 12 press Apply →

Zones Specify Boundary Types Check (Add) Enter, Name: out Select Type OUTFLOW Pick Entity : Faces, face representing outlet from the cyclone, see Figure 12 press Apply →

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Zones Specify Boundary Types Check (Add) Enter, Name: ash Select Type WALL Pick Entity : Faces, faces creating ash hopper, see Figure 12 press Apply →

outlet

velocity inlet

ash hopper

Figure 12: Boundary condition types.

0.2.3

Meshing geometry

Generation of appropriate mesh for cyclone geometry is not a trivial task. The flow inside a cyclone is fully 3 dimensional and complex. Proper simulation of  such flow require careful treatment of the mesh. Since this exercise is only to show possibilities of Fluent and we rather would like to show general procedure of simulating cyclone operation automatic mesh generator will be used. It is advised never to use shown here mesh for simulations of real object. See below 16

procedure for meshing cyclone geometry. Mesh Face Pick Faces, select all the faces Select Elements: Tri Select Type: Pave Check Spacing: Apply Enter Interval size 0.05 Press Apply →

Mesh Volume Pick Volumes, select all the volumes Select Elements: Tet/Hybrid Select Type: Tgrid Uncheck Spacing: Apply Press Apply →

Final mesh should contain around 20 000 cells. The last task to perform in Gambit is to export generated mesh to the file. File Export Mesh Press Browse to select destination folder. Enter name of the file, extension will be given by default. Press Accept →

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0.2.4

Setting Fluent parameters

Herewith procedure of setting up cyclone simulations in Fluent. Read mesh file ( mesh files have extension  msh) ˙ created in previous section. File Read Case... Define solver settings as default. Define Models Solver... Set turbulence modell Define Models Viscous... Select k  RNG turbulence model with option Swirl Dominated Flow In the Discrete Phase Model panel change Maximum Number of Steps to 10000 Set Injections Select Injection Type surface Select Release From Surfaces in (inis an inlet face) Select Material ash Select Diameter Distribution rosin-rammler-logarithmic Select tab Point Properties Enter Total Flow Rate (kg/s) equal to 0.001 Enter Min. Diameter (m) equal to 1e-6 Enter Max. Diameter (m) equal to 300e-6 →

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Enter Mean Diameter (m) equal to 150e-6 Enter Spread Parameter equal to 2.8 Enter Number of Diameters equal to 15 Select tab Turbulent Dispersion From Stochastic Tracking select Discrete Random Walk Model Enter Number of Tries equal to 5 Accept settings pressing OK Define material properties Define Materials... Change density for air Enter Density (kg/m3) equal to 1.094 Confirm changes pressing Change Create Change density for inert-particle ash Enter Density (kg/m3) equal to 2100 Confirm changes pressing Change Create Define operating condition Define Operating Conditions... Select Gravity Enter gravitation acceleration Z (m/s2) equal to 9.81 Accept settings pressing OK Define boundary condition Define Boundary Conditions... Select Zone in, press Set Enter Velocity Magnitude (m/s) equal to 7.98 Select Turbulence Specification Method Intensity and Hydraulic Diameter Enter Hydraulic Diameter (m) equal to 0.2 Accept settings pressing OK Select Zone ash, press Set Select tab DPM Under Discrete Phase Model Condition select Boundary Cond. Type trap Accept settings pressing OK Select Zone wall, press Set Select tab DPM Under Discrete Phase Reflection Condition select Normal constant Enter value equal to 0.8 Under Discrete Phase Reflection Condition select Tangent constant Enter value equal to 0.8 Accept settings pressing OK Close Boundary Condition panel Controls Solution... set up solver parameters Solve From Discretization select Momentum Second Order Upwind From Discretization select Turbulent Kinetic Energy Second Order Upwind From Discretization select Turbulent Dissipation Rate Second Order Upwind Accept settings pressing OK Initialize solution Solve Initialize Initialize... Press Init and close Solution Initialization panel Set solution monitoring option Solve Monitors Residual... Under Option select Plot For Residual continuity Convergence Criterion enter value equal to 10e-9 →

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Accept settings pressing OK save Fluent settings parameter in case file ( case files have extension  .cas) File Write Case..., enter file name and accept settings pressing OK →

0.2.5

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Performing calculations

Herewith we assume that Fluent is open and case file with cyclone is read. Type in Fluent command window it 100, (this command executes 100 iterations) Observe in Fluent result window residuals of the solved equations

Creating planes for extracting calculated variables

Running simulations on 3D domain we do not have direct access to solved variable inside the domain. Using Fluent post processing tools we can display only variables on the external boundary of the domain. In order to access variable inside the domain internal lines or planes needs to be created. The best of the flow visualization is to look at variables ( velocity, pressure field ) on the plane inside the domain. Planes can be placed at arbitral position selected by the user. From the number of methods of defining planes position available in Fluent we suggest to use 3 points method described below. Just in case we do not remember size of the domain geometry and its placement in the cartesian system we can display cartesian coordinates on the external boundaries of the domain geometry (see listing below ). Select Display Contours... From Option select Filled From Contours of  select Grid X-coordinate From Surfaces select wall Press Display Observe in Fluent result window boundary of the domain colored by X cartesian coordinate Repeat operation for Contours of  Y-coordinate and Z-coordinate →

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The cyclone axis is aligned with Z axis and crossing X = 0 and Y = 0 cartesian coordinates. Now we create plane crossing cyclone for Y = 0. Select Surface Plane... From Points enter, x0(m) = 1, x1(m) = 0, x2(m) = 0 y0(m) = 0, y1(m) = 0, y2(m) = 0 z0(m) = 0, z1(m) = 0, z2(m) = 1 (exact coordinates are not important, points can not be aligned, and in our case all  y variables must be equal to 0 ) →

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For New Surface Name enter desired name of the surface and press Create Close Plane Surface panel pressing Close You can repeat procedure above to create more planes in the arbitral positions inside analyzed domain. You can see created planes by displaying them in the Fluent result window. Select Display Grid... Select All from Edge Type From Surface select name of the creates palne Press Display →

Displaying Fluent variables on created planes

Fluent provide extremely powerful post processing tool. It allows to display on the screen all calculated variables and number of predefined derivatives of these variables. Here we show general procedure of displaying variables on created planes. Select Display Contours... From Option select Filled From Contours of , select Pressure... Static Pressure From Surfaces select plane created in previous step Press Display Observe in Fluent result window plane colored by static pressure field, one can see that the boundary of the domain are not visible, From Option select Draw Grid panel  Grid Display pop ups From Edge Type select Feature, and from Surfaces select domain boundary you want to display Press Display, now, when displaying contours of variables simultaneously domain  →

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boundary wireframe will be displayed 

From Contours of , select Velocity... Velocity Magnitude Press Display Observe in Fluent result window plane colored by velocity magnitude field, and the boundary of the domain →

Simulating ash flying inside a cyclone - particle tracking

In most of the cases mass load of the inert particles is small comparing to transport gas. If heat transfer between phases in not involved particle can be, without considerable error, traced within a gas phase in the frame of postprocessing. It means that first we simulate fluid flow of a gas phase. When convergence for continues phase is reached inert particle representing ash are traced employing

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Lagrangian model. See below for executing tracing procedure. Select Display Particle Tracks... From Option activate Draw Grid in order to see boundary of the domain ( see section above for explanation ) From Release from Injections select injection-0, (name can be different ) Select Track Single Particle Stream, (number of particle traced usually exceed  →

thousands and tracking procedure in lengthly even on fast computers, in order  to make this faster and be able to see particle paths on the screen we select this option  particle will be send only from one face at the inlet ) Press Display, (Fluent starts tracing procedure, after finishing displays particle paths in results window . In the main  Fluent window report of the tracing procedure is printed. Report  shows how many particles have been  traced, trapped, escaped, aborted and  incomplete, evaporated for inert particle is meaningless. Trapped are particle collected in the ash hopper. Escaped are these which left the cyclone through the outlet. Aborted are not traced by the solver due to numerical error.Incomplete are these for which  Max. Number of Steps was not enough to complete tracing. See section 0.2.4 for changing  Max. Number of Steps for particle tracking.) →

Useful option in particle tracking procedure is summary report. It can help in assessing efficiency of cyclone which is calculated as ratio of the ash mass flux collected inside ash hopper to the ash mass flux entering a cyclone. It also informs of the mass flux of incomplete traces. The regular report provide only the number of trapped, escaped and incomplete streams which is meaningless in assessing cyclone operation. See procedure below for activating summary report. Within Particle Trucks panel, select Summary from Report Type Deselect Track Single Particle Stream Press Track, (particle steams will not be displayed in results window ) See below example of summary report: number tracked = 3300, escaped = 419, aborted = 0, trapped = 2362, evaporated = 0, incomplete = 519 Fate

Number

- -- Incomplete T ra pp ed - Z on e 4 Escaped - Zone 5

- -- -- 519 2 36 2 419

Min - -- -- -- -- 5.646e-001 7 .4 18 e- 00 1 3.792e-0 01

Elapsed Time (s) Max Avg - -- -- -- -- - -- -- -- -- 4.080e+000 1.130e+000 3 .7 70 e+ 00 0 1 .5 09 e+ 00 0 3.53 0e+000 1.0 03e+000

Std Dev - -- -- -- -- 3.826e-001 3 .4 25 e- 00 1 5.647e-001

Injection, Min - -- -- -- -- -- -- -- -- -- injection-0 0 i nj ec ti on -0 4 24 injection-0 48

Index Max - -- -- -- -- -- -- -- -- -- injection-0 515 i nj ec ti on -0 2 03 inj ection-0 275

(*)- Mass Transfer Summary -(*) Fate ---I nc om pl et e T ra pp ed - Z on e 4 E sc ap ed - Z on e 5

Initial ---------2 .8 97 e- 00 8 9 .9 96 e- 00 4 3 .5 62 e- 00 7

Mass Flow (kg/s) Final Change ------------------2 .8 97 e- 00 8 0 .0 00 e+ 00 0 9 .9 96 e- 00 4 0 .0 00 e+ 00 0 3 .5 62 e- 00 7 0 .0 00 e+ 00 0

The most interesting is Mass Transfer Summary which shows mass fluxes of  Incomplete, Trapped and Escaped particle streams. General report shows only number of  incomplete, trapped and escaped particle stream. Sometimes even 21

large number of  escaped particle streams not impose low cyclone efficiency, because these streams could be low diameter particle streams. Hence in order to asses cyclone efficiency mass fluxes of  trapped and escaped particle streams needs to be compared. Escaped particle stream number indicate how many trace of the particle streams has not been completed. There are neither trapped nor escaped and traced has been finished inside domain. If number and mass flux of  incomplete stream is large we need to increase Max. Number of Steps under Discrete Phase Model panel opened from Define menu.

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