ANSYS 官方帮助文件 27-Turbo-Post

Chapter 27:Turbo PostprocessingThis tutorial is divided into the following sections:27.1. Introduction27.2. Prerequisites27.3. Problem Description27.4. Setup and Solution27.5. Summary27.1. IntroductionThis tutorial demonstrates the multistage turbomachinery postprocessing capabilities of ANSYS FLUENT.In this example, you will read the case and data files (without doing the calculation) and perform a numberof turbomachinery-specific postprocessing operations.This tutorial demonstrates how to do the following:•Define the topology of a turbomachinery model while using theta min and theta max.•Create surfaces for the display of 3D data.•Revolve 3D geometry to display a 360-degree image.•Report multistage turbomachinery quantities.•Display averaged contours for turbomachinery.•Display 2D contours for turbomachinery.•Display averaged XY plots for turbomachinery.27.2. PrerequisitesThis tutorial is written with the assumption that you have completed Introduction to Using ANSYS FLUENT: Fluid Flow and Heat Transfer in a Mixing Elbow (p.111) and that you are familiar with the ANSYS FLUENT navigation pane and menu structure.27.3. Problem DescriptionThe problem considered in this tutorial is an axial compressor shown schematically in Figure 27.1 (p.1008). The model comprises a single 3D sector of the compressor to take advantage of the circumferential periodicity in the problem.The flow of air through the compressor is simulated and the postprocessing capabilities of ANSYS FLUENT are used to display realistic, full 360-degree images of the solution obtained.Chapter 27:Turbo PostprocessingFigure 27.1 Problem Schematic27.4. Setup and SolutionThe following sections describe the setup and solution steps for this tutorial:27.4.1. Preparation27.4.2. Step 1: Mesh27.4.3. Step 2: General Settings27.4.4. Step 3: Defining the Turbomachinery Topology27.4.5. Step 4: Isosurface Creation27.4.6. Step 5: Contours27.4.7. Step 6: Reporting Turbo Quantities27.4.8. Step 7: Averaged Contours27.4.9. Step 8: 2D Contours27.4.10. Step 9: Averaged XY Plots27.4.1. Preparation1.Download turbo_postprocess.zip from the ANSYS Customer Portal or the User Services Centerto your working folder (as described in Preparation (p.4) of Introduction to Using ANSYS FLUENT inANSYS Workbench: Fluid Flow and Heat Transfer in a Mixing Elbow (p.1)).2.Unzip turbo_postprocess.zip.turbo.cas.gz and turbo.dat.gz can be found in the turbo_postprocess folder after unzipping the file.e FLUENT Launcher to start the 3D version of ANSYS FLUENT.For more information about FLUENT Launcher, see Starting ANSYS FLUENT Using FLUENT Launcher in the User’s Guide.The Display Options are enabled by default.Therefore, after you read in the case and data files, the mesh willbe displayed in the embedded graphics window.27.4.2. Step 1: Mesh1.Read the case and data files(turbo.cas.gz and turbo.dat.gz ).File →Read →Case & Data...When you select turbo.cas.gz ,turbo.dat.gz will be read automatically.27.4.3. Step 2: General SettingsGeneral1.Display the mesh.General →Display...a.Retain the default Edges option in the Options group box.b.Select Outline in the Edge Type list.c.Deselect all the surfaces from the Surfaces selection list and click the Outline button.d.Click Display .e.Rotate the view by clicking the Rotate Viewicon () in the toolbar, press the left mouse buttonand drag the mouse.To zoom in or out, press the Zoom In/Outbutton and press the leftmouse button and move the mouse up and down.To obtain an isometric display, select the Iso-metric view iconin the toolbar.f.Close the Mesh Display dialog box.27.4.3. Step 2: General SettingsChapter 27:Turbo PostprocessingExtraYou can use the right mouse button to check which zone number corresponds to each boundary.If you click the right mouse button on one of the boundaries displayed in the graphics window,its zone number, name, type, and other variables will be printed in the console.This feature isespecially useful when you have several zones of the same type and you want to distinguishbetween them quickly.27.4.4. Step 3: Defining the Turbomachinery TopologyYou will define the topologies of the flow domain in order to establish a turbomachinery-specific coordinate system. This coordinate system is used in subsequent postprocessing functions. Specifically, you will select the boundary zones that comprise the hub, shroud, inlet, outlet, and periodics.The boundaries may consist of more than one zone.The topologies that you define will be saved to the case file when you save the current model.Thus, if you read the saved case back into ANSYS FLUENT, you do not need to set up the topology again.For more information on defining turbomachinery topologies, see Defining the Turbomachinery Topologyin the User’s Guide.Turbo Topology...Define→1.Specify the surfaces representing the hub.a.Retain the default selection of Hub in the Boundaries group box.b.Select the surface that represent the hub (rotor-hub) in the Surfaces selection list.2.Specify the surfaces representing the casing.27.4.4. Step 3: Defining the Turbomachinery Topologya.Select Casing in the Boundaries group box.b.Select rotor-shroud in the Surfaces selection list.3.Specify the surfaces representing theta periodic.Theta periodic are all rotationally periodic boundary conditions surfaces (periodic boundary condition type) which border the turbo topology on the lateral (pitchwise) boundaries.a.Select Theta Periodic in the Boundaries group box.b.Select rotor-periodic-wall-1 and rotor-periodic-wall-2 in the Surfaces selection list.4.Specify the surfaces representing theta min.a.Select Theta Min in the Boundaries group box.b.Select rotor-blade-suction in the Surfaces selection list.Theta Min and Theta Max are all walls which may border the turbo topology on the lateral (pitchwise) boundaries.The “min” and “max” are determined by the right hand rule about the axis of rotation. Specifically, using the right hand rule, the min surfaces would have the minimum pitchwise coordinate and the max surfaces would have the maximum pitchwise coordinate.5.Specify the surfaces representing theta max.a.Select Theta Max in the Boundaries group box.b.Select rotor-blade-pressure in the Surfaces selection list.6.Specify the surface representing the inlet.a.Select Inlet in the Boundaries group box.b.Select rotor-inlet in the Surfaces selection list.7.Specify the surface representing the outlet.a.Select Outlet in the Boundaries group box.b.Select rotor-outlet in the Surfaces selection list.8.Retain the default name of new-topology-1 for the Turbo Topology Name.9.Click Define to set all the turbomachinery boundaries.Create a second topology to represent the stator.10.Specify the surfaces representing the hub.a.Select Hub in the Boundaries group box.b.Select the surface that represent the hub (stator-hub) in the Surfaces selection list.TipScroll down the Surfaces list to locate the surfaces representing the hub.11.Specify the surfaces representing the casing.a.Select Casing in the Boundaries group box.b.Select stator-shroud in the Surfaces selection list.12.Specify the surfaces representing theta periodic.a.Select Theta Periodic in the Boundaries group box.Chapter 27:Turbo Postprocessingb.Select stator-periodic-wall-1and stator-periodic-wall-2 in the Surfaces selection list.13.Specify the surfaces representing theta min.a.Select Theta Min in the Boundaries group box.b.Select stator-blade-suction in the Surfaces selection list.14.Specify the surfaces representing theta max.a.Select Theta Max in the Boundaries group box.b.Select stator-blade-pressure in the Surfaces selection list.15.Specify the surface representing the inlet.a.Select Inlet in the Boundaries group box.b.Select stator-inlet in the Surfaces selection list.16.Specify the surface representing the outlet.a.Select Outlet in the Boundaries group box.b.Select stator-outlet in the Surfaces selection list.17.Retain the default name of new-topology-2 for the Turbo Topology Name.18.Click Define to set all the turbomachinery boundaries.19.Close the Turbo Topology dialog box.ANSYS FLUENT will inform you that the turbomachinery postprocessing functions have been enabled, and the Turbo menu will appear in ANSYS FLUENT menu bar at the top of the console.You can define any number of turbo topologies in the Turbo Topology dialog box.This is especially useful when you have a model comprising multiple blade rows and you need to define more than one blade row simultaneously. Each topology can be assigned a specific name and accessed using the drop-down list in the Turbo Topology dialog box.For more information on defining turbomachinery topologies, see Defining the Turbomachinery Topologyin the User’s Guide.NoteYou can display the selected surfaces by clicking the Display button in the Turbo Topologydialog box.This is useful as a graphical check to ensure that all relevant surfaces have been selec-ted.27.4.5. Step 4: Isosurface CreationTo display results in a 3D model, you will need surfaces on which the data can be displayed. ANSYS FLUENT creates surfaces for all boundary zones automatically. In a general application, you may want to define additional surfaces for viewing results.The turbo postprocessing capabilities of ANSYS FLUENT allow you to define more complex surfaces, specific to the application and the particular topology that you defined. In this step, you will create surfaces of iso-meridional (marching along the streamwise direction) and spanwise (distance between the huband the shroud) coordinates in the compressor.1.Create surfaces of constant meridional coordinate.Surface→Iso-Surface...27.4.5. Step 4: Isosurface Creationa.Select Mesh... and Meridional Coordinate from the Surface of Constant drop-down lists.b.Enter 0.2 in the Iso-Values text field.c.Enter meridional-0.2 for New Surface Name.d.Click Create.NoteThe isovalues you enter for these turbo-specific surfaces are expressed as a percentageof the entire domain (i.e., you just defined a surface of meridional coordinate equal to20% of the path along the duct).e.Similarly, define surfaces of meridional coordinates equal to 0.4, 0.6, and 0.8.2.Create surfaces of constant spanwise coordinate.a.Select Mesh... and Spanwise Coordinate from the Surface of Constant drop-down lists.b.Enter 0.25 in the Iso-Values text field.c.Enter spanwise-0.25 for New Surface Name .d.Click Create .e.Similarly, define surfaces of spanwise coordinates equal to 0.5 and 0.75.3.Close the Iso-Surface dialog box.27.4.6. Step 5: ContoursGraphics and Animations→Contours →Set Up...1.Display filled contours of pressure on the meridional isosurfaces (Figure 27.2 (p.1016)).Chapter 27:Turbo Postprocessing27.4.6. Step 5: Contoursa.Make sure Filled is enabled in the Options group box.b.Retain the selection of Pressure...and Static Pressure from the Contours of drop-down lists.c.Select rotor-inlet,meridional-0.2,meridional-0.4,meridional-0.6,meridional-0.8, and rotor-outlet from the Surfaces selection list.d.Enable Draw Mesh in the Options group box.The Mesh Display dialog box will open.i.Retain the current settings and close the Mesh Display dialog box.e.Click Display.f.Rotate and zoom the display using the left and middle mouse buttons, respectively, to obtain theview shown in Figure 27.2 (p.1016).In Figure 27.2 (p.1016), you can observe the buildup of static pressure along the duct.Chapter 27:Turbo PostprocessingFigure 27.2 Filled Contours of Pressure on the Meridional Isosurfaces2.Display filled contours of Mach number (Figure 27.3 (p.1017)).a.Select Velocity... and Mach Number from the Contours of drop-down lists.b.Click Display.In Figure 27.3 (p.1017), you can observe locations at which the flow becomes slightly supersonic, about halfway through the duct.27.4.6. Step 5: ContoursFigure 27.3 Filled Contours of Mach Number on the Meridional Isosurfaces3.Display filled contours of Mach number on the spanwise isosurfaces (Figure 27.4 (p.1018)).a.Deselect all surfaces in the Surfaces selection list.b.Select spanwise-0.25,spanwise-0.5, and spanwise-0.75 from the Surfaces selection list.c.Click Display.The display in Figure 27.4 (p.1018) allows you to further study the variation of the Mach number inside the duct.You may want to explore using different combinations of surfaces to display the same oradditional variables.Figure 27.4 Filled Contours of Mach Number on the Spanwise Isosurfaces4.Display a 360-degree image of the Mach number contours on the hub and blade wall surfaces.a.Deselect all surfaces in the Surfaces selection list.b.Select rotor-hub ,rotor-blade-pressure and rotor-blade-suction from the Surfaces selection list.c.Click Display .d.Display the full 360-degree geometry.Graphics and Animations →Views...Chapter 27:Turbo Postprocessing27.4.6. Step 5: Contoursdialog box.i.Click the Define... button to open the Graphics Periodicity ArrayA.Select fluid-rotor in the Cell Zones list.This will select all the surfaces in the Associated Surfaces list.The default value for Number of Repeats is set to 16.The display is updated to give a full, 360 degree view.B.Click Set and close the Graphics Periodicity dialog box.The display will be updated to show the entire geometry (see Figure 27.5 (p.1020)).Chapter 27:Turbo PostprocessingFigure 27.5 Filled Contours of Mach Number on the 0.5 Spanwise Isosurfaceii.Close the Views dialog box.5.Close the Contours dialog box.NoteThis step demonstrated a typical view-manipulation task. See Postprocessing (p.961) for furtherexamples of postprocessing features.27.4.7. Step 6: Reporting Turbo QuantitiesThe turbomachinery report provides some tabulated information specific to the application and the defined topo-logy.For details, see Generating Reports of Turbomachinery Data in the User’s Guide.Turbo→Report...1.Retain the default selection of Mass-Weighted in the Averages list.2.Select new-topology-1 from the Turbo Topology drop down list.3.Click Compute .4.Close the Turbo Report dialog box.27.4.8. Step 7: Averaged ContoursTurbo averaged contours are generated as projections of the values of a variable averaged in the circumferential direction and visualized on an - plane.1.Disable the periodic repeats.Graphics and Animations →Views...a.Click the Define... button to open the Graphics Periodicity dialog box.i.Click Reset .27.4.8. Step 7: Averaged ContoursChapter 27:Turbo Postprocessingii.Close the Graphics Periodicity dialog box.b.Close the Views dialog box.2.Display filled contours of averaged static pressure (Figure 27.6 (p.1023)).Averaged Contours...Turbo→a.Retain the default selection of Pressure... and Static Pressure from the Contours of drop-downlists.b.Click Display.c.Close the Turbo Averaged Contours dialog box.Figure 27.6 Filled Contours of Averaged Static Pressure27.4.9. Step 8: 2D ContoursIn postprocessing a turbomachinery solution, it is often preferable to display contours on constant spanwise co-ordinates and then, project these contours onto a plane.This permits easier evaluation of the contours, especially for surfaces that are highly three-dimensional. ANSYS FLUENT allows you to display contours in this manner using the Turbo 2D Contours dialog box.1.Display 2D contours of Mach number (Figure 27.7 (p.1024)).Turbo →2D Contours...27.4.9. Step 8: 2D ContoursChapter 27:Turbo Postprocessinga.Select new-topology-1 from the Turbo Topology drop down list.b.Select Velocity... and Mach Number from the Contours of drop-down lists.c.Enter 0.5 for Normalised Spanwise Coordinates.NoteFor highly curved edges, if a surface is created very close to the curved edge the res-ulting surface may have some void spaces in it.d.Click Display.e the mouse to obtain the view shown in Figure 27.7 (p.1024).Figure 27.7 2D Contours of Mach Number on Surface of Spanwise Value 0.5f.Close the Turbo 2D Contours dialog box.27.4.10. Step 9: Averaged XY PlotsIn addition to displaying data on different combinations of complex 3D and flattened surfaces, the turbo postpro-cessing capabilities of ANSYS FLUENT allow you to display XY plots of averaged variables, relevant to the specific topology of a turbomachinery problem. In particular, you will be able to plot circumferentially-averaged valuesof variables as a function of either the spanwise coordinate or the meridional coordinate.1.Plot temperature as a function of the meridional coordinate (Figure 27.8 (p.1025)).Turbo→Averaged XY Plot...27.4.10. Step 9: Averaged XY Plotsa.Select Temperature... and Static Temperature from the Y Axis Function drop-down lists.b.Select Meridional Distance from the X Axis Function drop-down list.c.Enter 0.9 for the Fractional Distance.d.Click Plot.e.Close the Turbo Averaged XY Plot dialog box.Figure 27.8 Averaged XY Plot of Static Temperature on Spanwise Surface of 0.9 IsovalueChapter 27:Turbo Postprocessing27.5. SummaryThis tutorial demonstrated the use of some of the turbomachinery-specific postprocessing features of ANSYS FLUENT.These features can be accessed once you define the topology of the problem. More extensive general-purpose postprocessing features are demonstrated in Postprocessing (p.961). For additional inform-ation, see "Displaying Graphics" in the User’s Guide. Note that ANSYS CFD-Post also offers advanced post-processing tools for turbomachinery.The tutorial describing these tools is available in the CFD-Post Tutorials.。