Thomas when you design compressor or turbine blades, you generally have a surfaces (the blades) a given hub and a given shroud. What makes the compressor or turbine is the triplet blade, hub and shroud.
Sometimes, you have to move the hub or the shroud, or you want to re - use a blade in a new channel made by a different hub or shroud. Thius makes that sometimes it is useful to have the possibility to extend surfaces. We generally measure blades from hub to shroud, in what is called the span direction. You have a given number of design sections (or airfoils) that are used to build up the surface. Those sections correspond, in our way of doing, to given percentages of span : 0%, 10%, ..., 90%, 100%. Because you cannot design a blade without a channel... So : To properly design a blade you need to : - import a blade surface - intersect with a hub and a shroud - sometimes it necessitates extrusion in the span direction, on both extremities - determine your design sections and cut along those sections - modify the airfoils/sections you're interested in - build up the new surface of the blade. Note that you always have 0% and 100% sections as design sections... or approaching... which means that sometimes the hub and shroud intersections... can malfunction due to tolerance. So a 1% span extrusion is always usefull... Another point is that sometimes... when extruding... the airfoils become tri-corns... or crazy outer space shapes... Hope this helps Stéphan _______________________________________________ Pythonocc-users mailing list Pythonocc-users@gna.org https://mail.gna.org/listinfo/pythonocc-users
