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Usage

The usage of the filter similar to other filters with one small difference: Because it allows (and requires) selection of different parts of the multi-part mesh, it is necessary to load all needed parts of the mesh, not just the internal mesh. The figure crossref demonstrates a typical selection of OpenFOAM case mesh and patches for the Turbo Unwrap filter.

TurboUnwrap selection

Figure: Turbo Blade Post; Selection of multiple parts of the mesh.

The filter will transform the cylinder-like mesh into a box. Meaning of its new dimensions is described in the table crossref 3. In brief it can be said that the boundary img4 is the hub patch, the boundary img5 is the shroud patch, the boundary img6 1 is the one of inlet and outlet interfaces that is lower on the rotation axis and the boundary img7 is the other one (higher on rotation axis). The boundaries on minimal and maximal img8 2 coordinates are only artificial and were originally connected to each other. See also the figures in the section “Example”.

Also note that the filter transforms only cell data, so it may be necessary to apply the filter Cell data to point data afterwards to regain access to the point fields (which are necessary for usage of e.g. the Glyph filter).

Table: Coordinates of the “unwrapped” mesh. The coordinate $ \color{white} m$ is relative to the full length of the hub/shroud/streamline. The coordinate $ \color{white} \zeta$ is relative to the full local distance between hub and shroud.
 
SymbolMapped toRangeMeaning
$ \color{white} m$$ \color{white} x$$ \color{white} (0,1)$Distance along the hub/shroud/streamline.
$ \color{white} t$$ \color{white} y$$ \color{white} (0, 2\pi)$Circumferential angle.
$ \color{white} \zeta$$ \color{white} z$$ \color{white} (0,1)$Distance from the hub; the “span”.

Note that the filter passes all cell data without change except for the vector fields U and URel, which are transformed into the new coordinate system img17.

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Next: Examples Up: Turbo Unwrap filter Previous: Other parameters   Contents   Index

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