15.5.1. Turbo Surface: Geometry

Options available for Definition are:

  • Constant Span

  • Constant Streamwise Location

  • Constant Blade Aligned

  • Constant Blade Aligned Linear

  • Constant Theta

  • Cone

The Constant Span, Constant Streamwise Location, and Constant Theta options are similar to planes in that they can be bounded and have Slice or Sample types. For details, see Type.

 

15.5.1.1. Domains

See Selecting Domains.

 

15.5.1.2. Definition

  • Constant Span creates a surface at a fractional span value between the hub and shroud. For details, see Span Normalized.

  • Constant Streamwise Location creates a surface at a fractional streamwise distance between the inlet and outlet. For details, see Streamwise Location.

  • Constant Blade Aligned creates surfaces that are aligned with the leading and trailing edges of the blade. If the blade is curved, the surfaces are similarly curved.

  • Constant Blade Aligned Linear creates flat surfaces that approximate the leading and trailing edges of the blade.

  • Constant Theta creates a surface at a specific Theta value. For details, see Theta.

  • Cone uses the two supplied points to create a line. The cone is created where the user-defined line intersects the axis of rotation and Point 2:

The user-defined line is then rotated about the axis of origin to create the cone. If the line is parallel to the axis of rotation, a cylinder is created. If the line is normal to the axis of rotation, a disc is created.

The line can be described by Cartesian or cylindrical components. When entering cylindrical coordinates, only the axial distance and radius are required. The points can be entered or picked directly from the viewer.

Note:   Constant Theta and Cone methods are available even before turbo initialization has been performed because these methods do not depend on span or streamwise coordinates.

 

15.5.1.3. Bounds

The available types of Bounds for the Turbo Surface to be created can be seen by clicking   next to the Type box.

  • When None is selected, the Turbo Surface cuts through a complete cross-section of each domain specified in the Domains list. The Turbo Surface is bounded only by the limits of the domain.

  • Using Rectangular, you can enter the maximum and minimum value for the two dimensions on the Turbo Surface. The Turbo Surface is undefined in areas where the rectangle extends outside of the domains specified in the Domains list.

The Invert Surface Bounds check box reverses the effect of the surface bound. The surface is defined only in regions outside the bounding constraints.

 

15.5.1.4. Type

You can set the Type to either Slice or Sample.

Slice extends the Turbo Surface in all directions until it reaches the edge of the domain. Points on the Turbo Surface correspond to points where the Turbo Surface intersects an edge of the mesh. As a result, the number of points in a slice Turbo Surface is indirectly proportional to the mesh spacing.

Sample creates the Turbo Surface with rectangular bounds. The density of points on the Turbo Surface corresponds to the size of the bounds for your Turbo Surface in each of the Turbo Surface directions, and the value in the Samples box for each of the two directions that describe the Turbo Surface. You can type in the value in the Samples box, increase or decrease the value by 1 by clicking   or   respectively, or use the embedded slider (which has a maximum value of 998 and a minimum value of 2). A sample Turbo Surface is a set of evenly-spaced points which are independent of the mesh spacing.