The scope of this tutorial is to show the capability of RBF Morph to handle a parametric modellization of a real-life industrial problem. More specifically, the geometry is a turbine blade and it’s rotation and twist are parameterized; the mesh is then morphed successfully for a wide range of the parameters combinations, despite the presence of very close boundaries to be preserved.
In this practical application a simple strategy has been used considering two set of points extracted from the surfaces.
For the definition of the twisting problem, the first set is defined by all the nodes of the hub, the inlet, the outlet and the periodic boundary, for which a zero motion is assigned. The second set is instead defined by only the edge of the blade, for which the desired twisting movement is prescribed. The shroud is left as deformable (the default for RBF Morph, no input required for such definition) to accommodate the rotation of the tip.
The rotation of the whole blade is then obtained with slight modifications of the previous problem: the rotation is prescribed to all the nodes of the blade surface, and the hub is left free to deform to allow the rotation of the blade.
After generating the two solutions, they can be conveniently combined; for example a symmetric twist is shown in the video.
The video is presented here with no interruptions or cuts, in order to represent the real execution times, including the morphing stage.
In this example a two-parameter study is defined, setup and fully morphed in about 5 minutes, on a mesh made of almost 300’000 cells, all involved in the morphing stage.
However the morphing time can be significantly reduced by running Fluent in parallel, considering that RBF Morph scales almost linearly.
Blade model: courtesy of GridPro www.gridpro.com.