10.3.2. Defining Geometry from Profile Points

Profile point data can be used for the geometry of the blades and main passage.

Note:

  • If you plan to add blade blends (fillets) that use the rolling ball process with a constant radius, consider using the CAD From Profile Points input mode. For details, see Defining Geometry from Generated CAD: CAD From Profile Points.

  • Profile point data cannot be used to define secondary flow paths. However, you can add secondary flow paths from a CAD source by using the Profile Points With Secondary CAD input mode.

To define the geometry in TurboGrid using profile point data, you can do any of the following:

  • Load profile point data from a BladeEditor Geometry cell (in Workbench):

    1. In BladeEditor, create an ExportPoints feature. For details, see Export to Ansys TurboGrid in the TurboSystem User's Guide.

    2. In Workbench, attach a Geometry cell upstream of the Turbo Mesh cell.

    3. Set the Turbo Mesh cell properties. For details, see TurboGrid Turbo Mesh Cell Properties in the TurboSystem User's Guide.

    4. In TurboGrid, in the Geometry workspace, open the geometry browser, set Input Mode to Profile Points (or Profile Points With Secondary CAD) and configure the applicable settings in the geometry browser.

    5. Review the settings in the Geometry objects in the Mesh workspace, making and applying changes as required.

      For details, see The Geometry Objects in the Mesh Workspace.

  • Load profile point data from a BladeGen Blade Design cell (in Workbench):

    1. In Ansys Workbench, attach a Blade Design cell upstream of the Turbo Mesh cell.

    2. In TurboGrid, review the settings in the geometry browser in the Geometry workspace, making and applying changes as required.

      Note that Input Mode should be set to Profile Points.

    3. Review the settings in the Geometry objects in the Mesh workspace, making and applying changes as required.

      For details, see The Geometry Objects in the Mesh Workspace.

    Note that, in this case, some of the geometry objects in the Mesh workspace (such as Machine Data, Hub, Shroud, Blade Set, and Blade) have their settings taken from the upstream cell, and changes to these settings cannot be made in Ansys TurboGrid. Other settings in geometry objects are taken from the upstream cell by default, but can be overridden. To override a particular setting, select the appropriate check box in the object editor or the geometry browser. For example, although the machine rotation axis is, by default, taken from the upstream cell, you can reverse the rotation axis direction by first selecting the Override Theta Direction for Topology check box in the Machine Data object editor or the geometry browser, and then selecting Right Handed or Left Handed.

  • Load profile point data from a BladeGen *.inf file:

    1. Select File > Load TurboGrid Init File or click Load TurboGrid Init File   then select and open an *.inf file.

      The *.inf file contains machine data, the names of geometry definition files, the choice of coordinate system, and leading/trailing edge settings. For details on *.inf files, see BladeGen.inf File.

    2. Review the settings in the geometry browser in the Geometry workspace, making and applying changes as required. Note that Input Mode should be set to Profile Points.

    3. Review the settings in the Geometry objects in the Mesh workspace, making and applying changes as required. For details, see The Geometry Objects in the Mesh Workspace.

  • Load profile point data from separate curve (.curve or .crv) files:

    1. Select File > Load Profile Points Or CAD or click Load Profile Points Or CAD  .

    2. In the geometry browser in the Geometry workspace, specify curve files and make and apply other changes as required. Note that Input Mode should be set to Profile Points.

    3. Review the settings in the Geometry objects in the Mesh workspace, making and applying changes as required. For details, see The Geometry Objects in the Mesh Workspace.

    For details on curve files, see Curve File.

  • In the Mesh workspace, define the Machine Data object, then each of the remaining geometry objects separately.

    Note that, in the geometry browser in the Geometry workspace, Input Mode must be set to Profile Points.

Using the geometry browser with the Profile Points input mode is a convenient way to define multiple geometry objects, compared to editing each geometry object separately in the Mesh workspace. It is useful when you first open TurboGrid and when you want to use the same settings on a slightly modified geometry.

The information specified in the geometry browser is used to overwrite the corresponding information in the appropriate Geometry objects in the Mesh workspace. No other previously-defined settings are affected. For example, if a control angle is defined for the Hub object, it will not be changed by using the geometry browser.

The curve file for the blades can specify one or more blades for the blade row; one blade is generated for each blade defined in the curve file. If blade names are not included in the curve file, then names will be generated in the form Blade n, where n is an integer.

Note:  If a curve file that specifies multiple blades (defining a blade set) is used to define a particular blade object (stored in an object under the Blade Set object in the Mesh workspace), only the first blade in the file is used.

The following topics are discussed:

 

10.3.2.1. Objects in the Geometry Workspace (Profile Points Mode)

The objects in the Geometry workspace are not used when loading geometry from profile points. They are used only to verify that the geometry is imported correctly from a CAD source. For details, see Objects in the Geometry Workspace (CAD Mode).

 

10.3.2.2. Geometry Browser Settings (Profile Points Mode)

To access the geometry browser, switch to the Geometry workspace and then, if necessary, double-click a high-level object (either the Topological Entity Instances object or the CAD Families object) in the object selector.

The geometry browser settings for Profile Points mode are described next:

 
10.3.2.2.1. Point Data Definition
 
10.3.2.2.1.1. TurboGrid Curve Files

To specify a curve file, set a filename using a path relative to the working directory. You can click the corresponding Browse   icon to select a curve file using a browser.

 
10.3.2.2.1.2. Coordinates and Units

The Coordinates, Angle Units, and Length Units settings each apply to the hub, shroud, and blade files. Click   next to a setting to select the appropriate option. For a given setting, if there is no single option that applies to all three geometry files, select Curve Dependent and use the object selector in the Mesh workspace to define that setting individually for each geometry file.

 
10.3.2.2.2. Geometry Setup (Profile Points Mode)
 
10.3.2.2.2.1. Rotation (Profile Points Mode)

These settings are similar to the Rotation settings of the Machine Data object. For details, see Rotation.

 
10.3.2.2.2.2. # of Bladesets (Profile Points Mode)

A rotating machine component is made up of adjacent blades that are equally spaced around the circumference of the machine. The Theta extent of one blade set is calculated as 360 degrees divided by the number of main blades. Many rotating machine components have secondary and tertiary blades that are placed between the main blades. These are often called splitter blades. A blade set contains one main blade and optional splitter blades that repeat cyclically around the axis of the rotating machine component.

For rotating machine components without any splitter blades, the number of blade sets equals the total number of blades.

TurboGrid creates a mesh for one blade set only. The mesh can be copied and rotated using an Ansys CFX Pre-processor, if necessary, before it is solved in an Ansys CFX Solver.

 
10.3.2.2.2.3. Leading/Trailing Edge Definition on the Blade (Profile Points Mode Only)

Optionally select Cut-off or square. For details, see Cut-off or square.