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Blade profile |
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Blade profile |
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Ü Impeller | Blade profile 
To create blade profiles (main and splitter) the orthogonal blade thickness distribution for the hub and the shroud profile is used. By default the thickness is defined at leading edge, at trailing edge and at the control points of the blade. For the initial CFturbo-design typical values in dependence of the impeller diameter d2 are used (see Approximation functions).
The representation of the thickness distribution is made along the relative blade length (0 = leading edge, 1 = trailing edge).
The orthogonal blade thickness values are added to both sides of the blade mean line to create the pressure and suction sides of the blade.
In the panel Geometry the following properties for the profile design can be specified:
Design Mode
| Linear | Linear interpolation between control points |
| Freeform | Bezier splines are used for the thickness distribution |
| Linked to Main | Only for splitter blades: splitter profile is linked to main profile |
| Global point count | Global number of control points |
| Identic profiles | All profiles have the same thickness distribution |
| Flexible length position | Shifting control points in horizontal direction |
SS-PS-Coupling
| None | No coupling between suction side and pressure side |
| Symmetric | Symmetric thickness distribution: control points on suction and pressure side are coupled |
| Fixed thickness distribution | Shifting the thickness distribution to pressure/suction side whereas the distribution itself remains constant |
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Each thickness curve has a popup menu to add/remove polygon/Bezier points, to load or save the curve and to reset the distribution to default.
For Bezier curves a Polyline to Bezier conversion is possible. |
The Info panel represents information of the designed blade profile.
Min. cross section
Smallest cross section between 2 neighboring blades
Actual thickness
Actual orthogonal blade thickness values of hub and shroud profiles at leading edge, at trailing edge, after 1/3 and after 2/3 of the blade length
If the cells are colored red, then the thickness on leading/trailing edge is differing from the Target thickness.
Target thickness
Orthogonal blade thickness values for hub and shroud profiles at leading edge and at trailing edge as defined in the Blade properties dialog.
Please note that the blade thickness on leading and trailing edge should be modified in the Blade properties dialog only. In this case the blade angle calculation should be updated due to the blade blockage.
The Display options only influence the graphical representation. For instance, the visibility of the smallest cross section can be toggled.
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The Frontal view (switch above the diagram) represents the designed profiles in a frontal view, including diameters dN and d2.
Furthermore the smallest cross section between 2 neighboring profiles is displayed. |
Page url: http://www.cfturbo.com/fileadmin/content/manual/en/index.html?prof.html
