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9/9/2014 Chapter 3: BladeGen

https://www.sharcnet.ca/Software/Fluent14/help/wb_bm/bm_bladegen.html 1/6

Chapter 3: BladeGen

ANSYS BladeGen is a geometry creation tool that is specialized for turbomachinery blades. BladeGenhas its own documentation that can be accessed through the user interface, or by browsing the installationdirectory. The main documentation, “ANSYS BladeGen User's Guide”, is available from the Help menuin BladeGen. There, you will find general help, tutorials, and help on Vista CPD (for centrifugal pumps),which runs inside BladeGen.

Other Vista programs are available from Workbench, under the Component Systems and are documentedin the Workbench help:

See "Vista AFD" for details on using Vista AFD (for axial fans).

See "TurboSystem: Vista CCD" for details on using Vista CCD (for centrifugal compressors).

See "TurboSystem: Vista RTD" for details on using Vista RTD (for radial inflow turbines).

Note: ANSYS BladeGen and the Vista programs mentioned above are available only onWindows.

Note: Another Vista program, Vista TF, is for throughflow analyses in turbomachinery.It has a reference guide named "Vista TF Reference Guide" that is in this set ofdocumentation. You can access it by clicking the following link: Vista TFReference Guide.

To launch BladeGen from ANSYS Workbench, add the BladeGen component system to your projectschematic, then edit the Blade Design cell of that system.

The Blade Design cell has properties that need to be configured in order to transfer the blade geometryfrom BladeGen to BladeEditor. This transfer is represented by a link that connects a Blade Design cell toa Geometry cell.

A sample of the cell properties is shown in Figure 3.1.

Figure 3.1 Properties of the BladeGen Blade Design Cell



Table 3.1: BladeGen Blade Design Cell Properties describes each of the cell properties. These are relatedto the properties of the ImportBGD feature in BladeEditor (described at Table 4.3: Properties for theImportBGD Feature).

Table 3.1 BladeGen Blade Design Cell Properties

Group Name DescriptionImport Options Create Hub* If this property is selected, then BladeEditor will

create a HubProfile sketch for the non-flow pathhub geometry, and will create a revolved bodyfeature called HubBody.

Create All Blades If this property is selected, then BladeEditor willcreate all the blades using the number of bladesspecified in the BladeGen model.

If this property is not selected, then only the firstblade will be created.

Merge Blade Topology If this property is not selected, then BladeEditorwill create the blade with four facescorresponding to the leading edge, pressure side,trailing edge and suction side. This can make iteasier to create a structural mesh for the bladesin the Mechanical application.

If this property is selected, then the blade faceswill be merged where they are tangent to oneanother.

Blade Loft Direction If this property is set to Streamwise, thenBladeEditor will loft the blade surfaces in thestreamwise direction through curves that runfrom hub to shroud. This is the default becausethe surface is more well defined, especially forflank-milled blades.



If this property is set to Spanwise, thenBladeEditor will loft the blade surfaces in thespanwise direction through the blade profilecurves.

For an illustration of these lofting methods, seethe figure after this table.

Shroud Clearance This property specifies whether a shroudclearance is created. If None is selected, then noshroud clearance is created. To create a shroudclearance, choose either Relative Layer orAbsolute Layer. The blade(s) will be trimmedoff at the selected BladeGen output layer, andthe layer contour will be created in theLayerProfile sketch.

If Relative Layer is selected, then the selectedLayer Number is relative to the shroud layer,e.g., 1 implies the first layer closest to theshroud layer, 2 implies the second closest layerto the shroud, etc.

If Absolute Layer is selected, then the selectedlayer index counts up from the hub layer, whichis zero.

Create Fluid Zone* If this property is selected, then BladeEditor willcreate a StageFluidZone body for the flowpassage, and an Enclosure feature to subtract theblade body. The resulting Enclosure can be usedfor a CFD analysis of the blade passage.

Create NamedSelections*

If this property is selected, then BladeEditor willcreate NamedSelections (regions) for the typicalfaces of the blade passage, i.e., Blade, Hub,Shroud, Inflow, Outflow, PeriodicA andPeriodicB. These NamedSelections can be usedas selection groups in other ANSYS Workbenchapplications.

Note that this property is available only ifCreate Fluid Zone is selected.

Blade Extension (%) This property defines the surface extensionlength (as a percentage of the average hub toshroud distance) for the blade surfaces. Thesesurfaces are extended and then trimmed to theMasterProfile sketch to ensure that the bladesolid correctly matches the hub and shroudcontours.

Periodic Surface This property defines the surface extension



Extension (%) length (as a percentage of the average hub toshroud distance) for the periodic surfaces. Thesesurfaces are extended to ensure that theStageFluidZone is properly cut.

Periodic Surface Style

This property specifies the style of the periodicinterface surfaces.

If Three Pieces is selected, then the periodicsurface is created in three connected pieces: oneupstream of the blade, one within the passage,and one downstream of the blade. This style canbetter accommodate highly curved or twistedblades, and is similar to the ANSYS TurboGridstyle of periodic surface.

If One Piece is selected, then the periodicsurface is created as a single surface.

Note that this property is available only ifCreate Fluid Zone is set to Yes.

* These properties will only apply when you initially import the model. Any subsequent changes to theseproperties will not be propagated to downstream cells upon updating the latter.

Figure 3.2 shows how spanwise lofting and streamwise lofting differ.

Figure 3.2 Spanwise Lofting versus Streamwise Lofting



Once the ImportBGD feature has been created (for example, by updating the Geometry cell), changingthe following Blade Design cell properties will have no effect:

Create Hub

Create Fluid Zone

Create Named Selections

Note: In order to facilitate the use of a BladeGen model in another application (such asBladeEditor or ANSYS TurboGrid), you should always ensure that the model unitsare set. When you create a new BladeGen model (File > New > BladeGenModel), the default units are always “Unknown” (regardless of ANSYS Workbenchpreferences). In this case, select Model > Properties from the BladeGen mainmenu and set Model Units in the Model Property Dialog.



You can access a context menu for the Blade Design cell in the BladeGen component system by right-clicking the cell. Most of the commands that are available are standard, and are described in Systems andCells. The context menu commands that are specific to the Blade Design cell are described inTable 3.2: Context Menu Commands Specific to the BladeGen Blade Design Cell.

Table 3.2 Context Menu Commands Specific to the BladeGen Blade Design Cell

Command DescriptionEdit This command opens BladeGen. If the cell is up to date, then

BladeGen will load the associated BladeGen model.Import Existing Case This command opens a file browser for selecting a .bgd file.

This command is only available if the cell is in the EditRequired state. If this command is not available due to havingalready selected a .bgd file, and you want to make thecommand available so that you can select a different .bgd file,then choose the Reset command in the context menu.

Create New Blade CFD Mesh This command creates a linked[a] Mesh system and generatesa mesh for the associated BladeGen model. This command isavailable only if the cell is up to date and the geometry hasbeen saved (either by saving it from within BladeGen or byclosing the BladeGen window).

Also see Tips on using Automated Meshing.[a] Note that the link between systems causes the geometry to be imported, rather than loaded, intoBladeEditor. The blade will be dependent on the BladeGen BGD file, but you can still modify theHubProfile sketch that appears under the associated MerPlane feature. For more information onimporting and loading geometry into BladeEditor, see Importing Blades from ANSYS BladeGenin the TurboSystem User Guide and Loading and Modifying Blades from ANSYS BladeGen inthe TurboSystem User Guide.

Release 14.0 - © 2011 SAS IP, Inc. All rights reserved.

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