Chapter 30. Reporting Alphanumeric Data

ANSYS FLUENT provides tools for computing and reporting integral quantities at surfaces and boundaries. These tools enable you to find the mass flow rate and heat transfer rate through boundaries, the forces and moments on boundaries, and the area, integral, flow rate, average, and mass average (among other quantities) on a surface or in a volume. In addition, you can print histograms of geometric and solution data, set reference values for the calculation of nondimensional coefficients, and compute projected surface areas. You can also print or save a summary report of the models, boundary conditions, and solver settings in the current case. These features are described in the following sections.

• Section 30.1: Reporting Conventions

• Section 30.2: Creating Output Parameters

• Section 30.3: Fluxes Through Boundaries

• Section 30.4: Forces on Boundaries

• Section 30.5: Projected Surface Area Calculations

• Section 30.6: Surface Integration

• Section 30.7: Volume Integration

• Section 30.8: Histogram Reports

• Section 30.9: Discrete Phase

• Section 30.10: S2S Information

• Section 30.11: Reference Values

• Section 30.12: Summary Reports of Case Settings

• Section 30.13: Memory and CPU Usage

Reporting tools for the discrete phase are described in Section 23.7: Postprocessing for the Discrete Phase.

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30.1 Reporting Conventions For 2D problems, ANSYS FLUENT computes all integral quantities for a unit depth equivalent to 1 meter. This value can by adjusted to match the speciﬁc dimension of your application only by manually revising the Depth in the Reference Values dialog box (see Section 30.11: Reference Values).

i The default value of Depth will be equivalent to 1 meter, even if the units are changed for depth in the Set Units dialog box (e.g., if the units for depth are changed to cm in the Set Units dialog box, the value of Depth in the Reference Values dialog box will be 100 cm). For axisymmetric problems, all integral quantities are computed for an angle of 2π radi- ans.

30.2 Creating Output Parameters You can create output parameters, which allow you to compare reporting values for diﬀerent cases. These are single values generated by the four types of reports:

• Fluxes (Section 30.3: Fluxes Through Boundaries)

• Forces (Section 30.4: Forces on Boundaries)

• Surface integrals (Section 30.6.1: Generating a Surface Integral Report)

• Volume integrals (Section 30.7.1: Generating a Volume Integral Report)

In the Reports task page, click the Parameters... button to open the Parameters dialog box, where a list of created input parameters and output parameters will be listed. The list of Input Parameters is available after performing the steps outlined in Section 7.1.9: Defining and Viewing Parameters. The list of Output Parameters is available after clicking the Save Output Parameters... button in the Fluxes, Forces, Surface Integrals, and Volume Integrals dialog boxes. You can define the output parameters either through the various reporting dialog boxes, as described in the sections that follow, or through the Create menu. In the Create menu, you will find a list of four items:

Fluxes...

Forces...

Surface Integrals...

Volume Integrals...

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Selecting any one of these items will open their respective dialog boxes, where you will deﬁne the type of report you would like to generate. Details on how to generate the various reports are available in Sections 30.3, 30.4, 30.6.1, and 30.7.1. Once you have saved your output parameters, you can modify them by selecting the parameter in the Output Parameters list and clicking Edit.... This will open the report dialog box where you can make your changes. In addition, you can select any of the following under the More menu:

Delete displays a message in a dialog box, prompting you for a response to conﬁrm the deletion of the output parameter.

Rename allows you to edit the name of the output parameter through the Rename dialog box.

Print to Console reports values to the console window. If you select multiple output parameters, then the output includes values from multiple output parameters.

Print All to Console outputs the values from all output parameters to the console window.

Write... allows you to store the output to a ﬁle. A dialog box is displayed allowing you to provide a ﬁle name.

Write All... prompts you for a ﬁle name and then writes the values for all of the output parameters to a ﬁle.

30.3 Fluxes Through Boundaries This section contains information about generating a ﬂux report. For more background information, see Section 20.1: Fluxes Through Boundaries in the separate Theory Guide.

30.3.1 Generating a Flux Report To obtain a report of mass ﬂow rate, total heat transfer rate, total sensible heat transfer rate, or radiation heat transfer rate on selected boundary zones, use the Flux Reports dialog box (Figure 30.3.1). Reports −→ Fluxes −→ Set Up...

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Figure 30.3.1: The Flux Reports Dialog Box

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The steps for generating the report are as follows:

1. Specify which ﬂux computation you are interested in by selecting Mass Flow Rate, Total Heat Transfer Rate, Total Sensible Heat Transfer Rate, or Radiation Heat Transfer Rate under Options.

2. In the Boundaries list, choose the boundary zone(s) on which you want to report ﬂuxes. If you want to select several boundary zones of the same type, you can select that type in the Boundary Types list instead. All of the boundaries of that type will be selected automatically in the Boundaries list (or deselected, if they are all already selected). Another shortcut is to specify a Boundary Name Pattern and click Match to select boundary zones with names that match the speciﬁed pattern. For example, if you specify wall*, all boundaries whose names begin with wall (e.g., wall-1, wall-top) will be selected automatically. If they are all selected already, they will be deselected. If you specify wall?, all boundaries whose names consist of wall followed by a single character will be selected (or deselected, if they are all already selected).

3. Click Save Output Parameter.... The Save Output Parameter dialog box (Figure 30.3.2) will open where you will specify the name of the newly created output parameter, or overwrite an existing output parameter of the same type. The default report name format is report-type-n (e.g. ﬂux-1).

Figure 30.3.2: The Save Output Parameter Dialog Box

After the output parameter is created, it is listed in the Parameters dialog box, accessed via the Parameters... button in the Reports task page. You can create any number of output parameters of this report type.

4. Click the Compute button to display the results of the selected flux computation for each selected boundary zone. The Net Results field will show the summation of the individual zone flux results.

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i Additional steps must be taken prior to generating a flux report for an interior boundary zone that has the same fluid defined on either side. In such a case, the area vectors of the cell faces associated with the zone may have been automatically defined in an inconsistent manner when the mesh file was read into the solver. Since the flux for each individual cell face is calculated with respect to its area vector, such an inconsistency leads to inaccurate results when the face fluxes are summed to calculate the total flux of the boundary zone. To ensure accurate flux results for such an interior zone, you must orient the area vectors by changing the definition of the zone Type to wall. You should then change the Type back to interior and proceed to generate the flux report. Note that the fluxes are reported exactly as computed by the solver. Therefore, they are inherently more accurate than those computed with the Flow Rate option in the Surface Integrals dialog box (described in Section 30.6: Surface Integration).

30.3.2 Flux Reporting for Reacting Flows To report heat transfer for reacting flows, one of models in the Species Model dialog box must be enabled for the Total Sensible Heat Transfer Rate option to appear in the Flux Reports dialog box. For reacting flows, ANSYS FLUENT produces two kinds of reports which use a different treatment at the flow boundaries:

• Total Heat Transfer Rate reports the total enthalpy flux, which consists of the total energy plus the species formation enthalpies. The heat rate based on this definition is a conserved quantity in reacting flows. See Section 5.2.1: Heat Transfer Theory in the separate Theory Guide for details.

• Total Sensible Heat Transfer Rate reports the total energy flux as defined in Equa- tion 5.2-2 in the separate Theory Guide. Note that in reacting flows, this is not a conserved quantity and the addition or removal of heat due to the chemical reactions (Equation 5.2-10 in the separate Theory Guide) is reported separately in the Heat of Reaction Source field, as shown in Figure 30.3.3. If you have more than one reaction defined in your case, the Heat of Reaction Source reported is the sum of the heat for all reactions. For exothermic reactions the Heat of Reaction Source is reported as a positive quantity, while for endothermic reactions it will be a negative quantity.

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Figure 30.3.3: The Flux Reports Dialog Box

i Note that both the Total Heat Transfer Rate and Total Sensible Heat Transfer Rate options report a Net Result, which may be used as an indication of the energy balance for the case. In general, and if heat sources other than the heat of reaction and DPM are not included in your problem, the Net Result reported in both the Total Heat Transfer Rate and Total Sensible Heat Transfer Rate options should be a small number for a converged calculation. However, if a reacting case is not well converged for both energy and species transport equations, the Net Result reported in the Total Heat Transfer Rate and Total Sensible Heat Transfer Rate options may diﬀer. In that case, you may consider iterating further to achieve a fully converged solution. In addition, please refer to the sections that follow for special considerations when including particles, multiphase models, or other volumetric energy sources.

i Please note that for the non-premixed and partially premixed models the Heat of Reaction Source is calculated as the diﬀerence of the net Total Heat Transfer Rate and the net Total Sensible Heat Transfer Rate. The Heat of Reaction ﬁeld function is not available for the non-premixed and partially- premixed models.

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Flux Reporting with Particles If you are using the discrete phase model (DPM), the contributions from the particle injections are reported separately and are included in the net mass and heat balance results. Consequently, the Mass Flow Rate report includes the DPM Mass Source, the Total Heat Transfer Rate report includes the DPM Enthalpy Source, and the Total Sensible Heat Transfer Rate includes the DPM Sensible Enthalpy Source (Figure 30.3.4).

Figure 30.3.4: The Flux Reports Dialog Box with DPM

i In the case of reacting ﬂows with the DPM model, the Heat of Reaction Source entry reports the heat of all homogeneous reactions in the contin- uous phase, while the heat released or consumed due to particle reactions (e.g. char combustion) is reported in the DPM Sensible Enthalpy Source ﬁeld.

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Flux Reporting with Multiphase If you are using any of the multiphase models, the mass or heat rates can be reported separately for each phase and for the mixture phase. Please note that if your multiphase model includes mass or heat transfer processes between phases, the mass and heat trans- ferred across the phases will be reported as an imbalance in the report of each phase. In order to check the overall balances for the multiphase cases you should select the mixture phase for your report. In that case, the report will include the sum of the ﬂuxes and sources for all phases included in your model. Finally, if you are solving a multiphase problem that includes chemical reactions, you should be aware of the following conventions when you are requesting a Total Sensible Heat Transfer Rate report:

• If you select one of the phases with gas phase chemical reactions, the Heat of Reaction Source will only include contributions from reactions in the particular phase.

• When you report the Total Sensible Heat Transfer Rate for the mixture phase, the Heat of Reaction Source entry will report the sum of the heat of reaction of all gas phase reactions in all phases plus the heat of any heterogeneous reactions that take place.

Flux Reporting with Other Volumetric Sources The reported mass and heat balances address the ﬂow that enters or leaves the domain through boundaries and the contributions from DPM sources; they do not include the contributions from user-deﬁned and other volumetric sources, such as the heat exchanged in the Heat Exchanger Model. For this reason, a mass or heat imbalance may be reported. In that case, and in a converged calculation, the reported imbalance will be equal to the volumetric source.

30.4 Forces on Boundaries For selected wall zones, you can compute and report the forces along a specified vector, the moments about a specified center and along a specified axis, and the coordinates of the center of pressure. This feature is useful for reporting, for instance, aerodynamic quantities such as lift, drag, and moment coefficients, as well as the center of pressure for an airfoil. For additional information about forces, moments, and the center of pressure, see Sec- tion 20.2.1: Computing Forces, Moments, and the Center of Pressure in the separate Theory Guide.

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30.4.1 Generating a Force, Moment, or Center of Pressure Report To obtain a report (for selected wall zones) of forces along a specified vector, moments about a specified center and along a specified axis, or the center of pressure, use the Force Reports dialog box (Figure 30.4.1). Reports −→ Forces −→ Set Up...

Figure 30.4.1: The Force Reports Dialog Box

The steps for generating the report are as follows:

1. Specify the type of report in which you are interested by selecting Forces, Moments, or Center of Pressure from the Options list.

2. Define the settings associated with report you are generating: (a) For a force report, enter the X, Y, and Z components of the Force Vector along which the forces will be computed. (b) For a moment report, enter the X, Y, and Z coordinates of the Moment Cen- ter about which the moments will be computed, as well as the X, Y, and Z components of the Moment Axis along which the moments will be computed. (c) For a center of pressure report, define the line (for 2D geometries) or plane (for 3D geometries) on which you want to calculate the center of pressure. The line or plane must have one of its coordinate values fixed (e.g., a line defined as y = 10). Select the axis (X, Y, or Z) in the Coordinate group box, and then enter the fixed Value. See the example at the end of this section for further details.

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i If Fx (the x-component of the force) is zero, then either the Y or Z coordinate can be fixed. If Fy is zero, then either the X or Z coordinate can be fixed. If Fz is zero, then either the X or Y coordinate can be fixed.

3. In the Wall Zones list, select the wall zone(s) for which you want a report of the forces, moments, or pressure center. If you have a large number of wall zones, it may be useful to specify a Wall Name Pattern and click Match. This selects all of the wall zones with names that match the speciﬁed pattern. For example, if you specify out*, all walls whose names begin with out (e.g., outer-wall-top, outside-wall) will be selected automatically. If a wall zone that matches the name pattern is already selected when Match is clicked, it will be deselected. If you specify out?, all walls whose names consist of out followed by a single character will be selected (or deselected, if they are already selected).

4. Click Save Output Parameter.... The Save Output Parameter dialog box (Figure 30.3.2) will open where you will specify the name of the newly created output parameter, or overwrite an existing output parameter of the same type. The default report name format is report-type-n (e.g. force-1). After the output parameter is created, it is listed in the Parameters dialog box. You can create any number of output parameters of this report type.

5. Click the Print button if you want the results displayed in the console window, or click Write... to save it to a file. If you selected Forces under Options, the pressure force, viscous force (if appropriate), total forces, pressure coefficient, viscous coefficient, and total coefficients for each selected wall zone will be displayed or saved. If you selected Moments, the pressure moments, viscous moments (if appropriate), total moments, pressure coefficient, viscous coefficient and total coefficients for the wall zones about the specified center will be displayed or saved. Additionally, the moments and coefficients in the direction of the specified axis will be displayed or saved. The report will include the values for the individual wall zones, as well as the net values for all of the wall zones combined. See Section 20.2.1: Computing Forces, Moments, and the Center of Pressure in the separate Theory Guide for details about computing forces and moments. If you selected Center of Pressure, then ANSYS FLUENT displays or saves the coordinates about which the moment is zero. i You cannot save your output parameter if Center of Pressure is selected.

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i Note that the reported force and moment coeﬃcients are a function of the values entered in the Reference Values task page (as described in Sec- tion 20.2.1: Computing Forces, Moments, and the Center of Pressure in the separate Theory Guide). Therefore, appropriate values must be entered in the Reference Values task page to get meaningful results.

Example To demonstrate how you would generate and interpret the center of pressure report, consider an airfoil of chord length 1 m (shown in Figure 30.4.2).

cp y = 10

0 0.2 x = 0.4126 1.2 x

Figure 30.4.2: An Airfoil with its Computed Center of Pressure

Open the Force Reports dialog box and perform the steps that follow. Reports −→ Forces −→ Set Up...

1. Select Center of Pressure from the Options list.

2. Deﬁne the line on which the center of pressure will be calculated. In this case, the Y coordinate for the line has a ﬁxed Value of 10. 3. Select the Wall Zones that are relevant for the computation.

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Figure 30.4.3: The Force Reports Dialog Box for a Center of Pressure Report

4. Click Print to have the coordinates of the center of pressure displayed in the console window.

The report generated will be in the following form:

Pressure Center Coordinates (in m): X = 0.41267981 Y = 10

30.5 Projected Surface Area Calculations You can use the Projected Surface Areas dialog box (Figure 30.5.1) to compute an esti- mated area of the projection of selected surfaces along the x, y, or z axis (i.e., onto the yz, xz, or xy plane). Reports −→ Projected Areas −→ Set Up... The steps for calculating the projected area are as follows:

1. Select the Projection Direction (X, Y, or Z). 2. Choose the surface(s) for which the projected area is to be calculated in the Surfaces list. 3. Set the Min Feature Size to the length of the smallest feature in the geometry that you want to resolve in the area calculation. (You can just use the default value to start with, if you are not sure of the size of the smallest geometrical feature.)

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Figure 30.5.1: The Projected Surface Areas Dialog Box

4. Click on Compute. The area will be displayed in the Area box and in the console window.

5. To improve the accuracy of the area calculation, reduce the Min Feature Size by half and recompute the area. Repeat this step until the computed Area stops changing (or you reach memory capacity).

This feature is available only for 3D domains.

30.6 Surface Integration For additional information about surface integrals, see Section 20.3.1: Computing Surface Integrals in the separate Theory Guide.

30.6.1 Generating a Surface Integral Report To obtain a report for selected surfaces of the area or mass flow rate or the integral, flow rate, sum, facet maximum, facet minimum, vertex maximum, vertex minimum, or mass-, area-, facet-, or vertex-averaged quantity of a specified field variable, use the Surface Integrals dialog box (Figure 30.6.1). Reports −→ Surface Integrals −→ Set Up...

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Figure 30.6.1: The Surface Integrals Dialog Box

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The steps for generating the report are as follows:

1. Specify which type of report you are interested in by selecting Area, Integral, Area- Weighted Average, Flow Rate, Mass Flow Rate, Mass-Weighted Average, Sum, Facet Average, Facet Minimum, Facet Maximum, Vertex Average, Vertex Minimum, or Vertex Maximum in the Report Type drop-down list.

2. If you are generating a report of area or mass flow rate, skip to the next step. Otherwise, use the Field Variable drop-down lists to select the field variable to be used in the surface integrations. First, select the desired category in the upper drop-down list. You can then select a related quantity from the lower list. (See Chapter 31: Field Function Definitions for an explanation of the variables in the list.)

3. In the Surfaces list, choose the surface(s) on which to perform the surface integration. If you want to select several surfaces of the same type, you can select that type in the Surface Types list instead. All of the surfaces of that type will be selected automatically in the Surfaces list (or deselected, if they are all selected already). Another shortcut is to specify a Surface Name Pattern and click Match to select surfaces with names that match the speciﬁed pattern. For example, if you specify wall*, all surfaces whose names begin with wall (e.g., wall-1, wall-top) will be selected automatically. If they are all selected already, they will be deselected. If you specify wall?, all surfaces whose names consist of wall followed by a single character will be selected (or deselected, if they are all selected already).

4. Click Save Output Parameter.... The Save Output Parameter dialog box (Figure 30.3.2) will open where you will specify the name of the newly created output parameter, or overwrite an existing output parameter of the same type. The default report name format is report-type-n (e.g. surface-integral-1). After the output parameter is created, it is listed in the Parameters dialog box. You can create any number of output parameters of this report type.

5. Click on the Compute button. Depending on the type of report you have selected, the label for the result will change to Area, Integral, Area-Weighted Average, Flow Rate, Mass Flow Rate, Mass-Weighted Average, Sum of Facet Values, Average of Facet Values, Minimum of Facet Values, Maximum of Facet Values, Average of Surface Vertex Values, Minimum of Vertex Values, or Maximum of Vertex Values, as appropriate. The computed results will also be printed in the ANSYS FLUENT console window.

6. To save the computed results to a ﬁle, click the Write... button and specify the ﬁlename in the resulting Select File dialog box.

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Note the following items:

• Mass averaging “weights” toward regions of higher velocity (i.e., regions where more mass crosses the surface).

• Flow rates reported using the Surface Integrals dialog box are not as accurate as those reported with the Flux Reports dialog box (described in Section 30.3: Fluxes Through Boundaries).

• The facet and vertex average options are recommended for zero-area surfaces.

30.7 Volume Integration For additional information about volume integrals, see Section 20.4.1: Computing Volume Integrals in the separate Theory Guide.

30.7.1 Generating a Volume Integral Report To obtain a report (of quantities such as the volume, sum, minimum, maximum, volume integral, volume-weighted average, mass-weighted integral, or mass-weighted average) for selected cell zones for a speciﬁed ﬁeld variable, use the Volume Integrals dialog box (Figure 30.7.1). Reports −→ Volume Integrals −→ Set Up...

Figure 30.7.1: The Volume Integrals Dialog Box

The steps for generating the report are as follows:

1. Specify which type of report you are interested in by selecting Volume, Sum, Max, Min, Volume Integral, Volume-Average, Mass Integral, or Mass-Average under Options.

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2. If you are generating a report of volume, skip to the next step. Otherwise, use the Field Variable drop-down lists to select the ﬁeld variable to be used in the integral, sum, or averaged volume integrations. First, select the desired category in the upper drop-down list. You can then select a related quantity from the lower list. (See Chapter 31: Field Function Deﬁnitions for an explanation of the variables in the list.)

3. In the Cell Zones list, choose the zones on which to compute the volume, sum, max, min, volume integral, volume-weighted average, mass integral, or mass-averaged quantity.

4. Click Save Output Parameter.... The Save Output Parameter dialog box (Figure 30.3.2) will open where you will specify the name of the newly created output parameter, or overwrite an existing output parameter of the same type. The default report name format is report-type-n (e.g. volume-integral-1). After the output parameter is created, it is listed in the Parameters dialog box. You can create any number of output parameters of this report type.

5. Click on the Compute button. Depending on the type of report you have selected, the label for the result will change to Total Volume, Sum, Max, Min, Total Volume Integral, Volume-Weighted Average, Total Mass-Weighted Integral, or Mass-Weighted Average, as appropriate. The computed results will also be printed in the ANSYS FLUENT console window.

6. To save the computed results to a ﬁle, click the Write... button and specify the ﬁlename in the resulting Select File dialog box.

30.8 Histogram Reports In ANSYS FLUENT, you can print geometric and solution data in the console (text) window in histogram format or plot a histogram in the graphics window. Graphical display of histograms and the procedures for deﬁning a histogram are discussed in Sec- tion 29.9.8: Histograms. The number of cells, the range of the selected variable or function, and the percentage of the total number of cells in the interval will be reported, as in the example below:

0 cells below 1.195482 (0 %) 2 cells between 1.195482 and 1.196048 (4.1666667 %) 1 cells between 1.196048 and 1.196614 (2.0833333 %) 0 cells between 1.196614 and 1.19718 (0 %) 0 cells between 1.19718 and 1.197746 (0 %) 2 cells between 1.197746 and 1.198312 (4.1666667 %) 1 cells between 1.198312 and 1.198878 (2.0833333 %)

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6 cells between 1.198878 and 1.199444 (12.5 %) 9 cells between 1.199444 and 1.20001 (18.75 %) 25 cells between 1.20001 and 1.200576 (52.083333 %) 2 cells between 1.200576 and 1.201142 (4.1666667 %) 0 cells above 1.201142 (0 %)

To generate such a printed histogram, use the Histogram dialog box. Reports −→ Histogram −→ Set Up... Follow the instructions in Section 29.9.8: Histograms for generating histogram plots, but click on Print instead of Plot to create the report.

30.9 Discrete Phase ANSYS FLUENT allows you to write particle states (position, velocity, diameter, temperature, and mass ﬂow rate) to ﬁles at various boundaries and planes (lines in 2D) using the Sample Trajectories dialog box (Figure 23.7.4). Information about discrete phase reporting is discussed in detail in Section 23.7.6: Sampling of Trajectories, Sec- tion 23.7.7: Histogram Reporting of Samples, and Section 23.7.8: Summary Reporting of Current Particles.

30.10 S2S Information ANSYS FLUENT allows you to view the values of the view factor and radiation emitted from one zone to another. You will use the S2S Information dialog box (Figure 13.3.18) to generate a report of these values. For details on reporting S2S information, refer to Section 13.3.8: Reporting Radiation in the S2S Model.

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30.11 Reference Values You can control the reference values that are used in the computation of derived physical quantities and nondimensional coeﬃcients. These reference values are used only for postprocessing. Some examples of the use of reference values include the following:

• Force coeﬃcients use the reference area, density, and velocity. In addition, the pressure force calculation uses the reference pressure.

• Moment coeﬃcients use the reference length, area, density and velocity. In addition, the pressure force calculation uses the reference pressure.

• Reynolds number uses the reference length, density, and viscosity.

• Pressure and total pressure coeﬃcients use the reference pressure, density, and velocity.

• Entropy uses the reference density, pressure, and temperature.

• Skin friction coeﬃcient uses the reference density and velocity.

• Heat transfer coeﬃcient uses the reference temperature.

• Turbomachinery eﬃciency calculations use the ratio of speciﬁc heats.

30.11.1 Setting Reference Values To set the reference quantities used for computing normalized flow-field variables, use the Reference Values dialog box (Figure 30.11.1). Reference Values You can input the reference values manually or compute them based on values of physical quantities at a selected boundary zone. The reference values to be set are Area, Density, Enthalpy, Length, Pressure, Temperature, Velocity, dynamic Viscosity, and Ratio Of Specific Heats.

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Figure 30.11.1: The Reference Values Task Page

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For 2D problems, an additional quantity, Depth, can also be deﬁned. This quantity will be used for reporting ﬂuxes and forces, as well as relevant variables computed using the Surface Integrals dialog box and the Volume Integrals dialog box (e.g. Area, Flow Rate, Mass Flow Rate, Volume, etc.). You should verify that the value and units of Depth corresponds to the depth dimension of your application prior to reporting any of the variables above. i The units for Depth are set independently from the units for Length in the Set Units dialog box. If you want to compute reference values from the conditions set on a particular boundary zone, select the zone in the Compute From drop-down list. Note, however, that depending on the boundary condition used, only some of the reference values may be set. For example, the reference length and area will not be set by computing the reference values from a boundary condition; you will need to set these manually. To set the values manually, simply enter the value for each under the Reference Values heading.

30.11.2 Setting the Reference Zone If you are solving a flow involving multiple reference frames or sliding meshes, you can plot velocities and other related quantities relative to the motion of a specified “reference zone”. Choose the desired zone in the Reference Zone drop-down list. Changing the reference zone allows you to plot velocities (and total pressure, temperature, etc.) relative to the motion of different zones. See Chapter 10: Modeling Flows with Rotating Reference Frames for details about postprocessing of relative quantities.

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30.12 Summary Reports of Case Settings You may sometimes ﬁnd it useful to get a report of the current settings in your case. In ANSYS FLUENT, you can list the settings for physical models, boundary conditions, material properties, and solver controls. This report allows you to get an overview of your current problem deﬁnition quickly, instead of having to check the settings in each dialog box.

30.12.1 Generating a Summary Report To generate a summary report you will use the Input Summary dialog box (Figure 30.12.1).

Report −→Input Summary...

Figure 30.12.1: The Input Summary Dialog Box

The steps are as follows:

1. Select the information you would like to see in the report (Models, Boundary Con- ditions, Solver Controls, and/or Material Properties) in the Report Options list.

2. To print the information to the ANSYS FLUENT console window, click on the Print button. To save the information to a text ﬁle, click on the Save... button and specify the ﬁlename in the resulting Select File dialog box.

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30.13 Memory and CPU Usage There are two types of system reporting, which are accessed using the text interface, that can be performed while running ANSYS FLUENT processes:

• Reporting the status of each of the ANSYS FLUENT processes, including memory and CPU usage (report/system/proc-stats).

• Reporting the status of the machines where ANSYS FLUENT processes have been spawned, including memory and CPU status (report/system/sys-stats).

i Note that the report/system/sys-stats text command is only applicable for Windows (ntx86 and win64) and Linux (lnamd64, lns86, and lnia64) platforms. Similarly, the report/system/proc-stats text command is only applicable for Windows, Linux, and AIX platforms. The type of information you can expect to see printed to the console when running in parallel, using the report/system/proc-stats text command, is

------| Mem Usage (MB) | CPU Time Usage (Seconds) ID | Current Peak Page Fault | User Kernel Elapsed ------host | 31.2422 285.242 9.439e+004 | 34.4531 1.90625 269.593 n0 | 525.949 743.438 3.933e+005 | 20.7656 3.70313 264.406 n1 | 516.063 737.438 3.867e+005 | 84.2813 166.328 264.437 ------Total | 1073.25 1766.12 8.744e+005 | 139.5 171.938 ------

Under Mem Usage (MB)

Current is the virtual memory usage at this very moment.

Peak is the peak virtual memory usage.

Page Fault is the number of page faults that have occurred.

Under CPU Time Usage (Seconds):

User is the CPU time used by user processes.

Kernel is the CPU time used by system kernel.

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Elapsed is the wall clock time elapsed since the process startup.

When using the report/system/sys-stats text command, where ANSYS FLUENT processes have been spawned on ﬁve machines, the following results are displayed:

------| CPU | System Mem (MB) Hostname | Number Clock (MHz) Load | Total Available ------deva01 | 2 2211.38 0.2 | 32205.2 31479 deva03 | 2 2211.34 0 | 32205.2 21560.4 deva04 | 2 2211.34 0 | 16093.7 12075.8 deva05 | 2 2211.34 0 | 16093.7 14624.5 deva06 | 2 2211.34 0.07 | 16093.7 12095.4 ------Total | 10 - - | 112691 91835.2 ------

Under CPU

Number is the number of processors on the machine.

Clock is the processor speed.

Load is the work load on the machine.

Under System Mem (MB)

Total is the total system memory on the machine.

Available is the available system memory on the machine.

You can use the two commands together to plan ANSYS FLUENT jobs and machines accordingly. It may also be useful to diagnose performance problems.

Release 12.0 c ANSYS, Inc. January 30, 2009 30-25 Reporting Alphanumeric Data

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