Defining Surface Regions
Before you define a surface region, you must specify the outline that defines the region. If you plan to define multiple regions, be sure to create the defining contour for each region as a separate feature; do not group all the contours in one feature. If you do, Creo Simulate will be unable to region the surface.
You can use one of the following methods to define the surface region:
Split by sketch
You can use the sketch tool to create an internal sketch of the boundaries of the surface region or you can use an external sketch to define the surface region contours. In both cases, the sketch is extruded perpendicular to the sketching plane. The resulting internal surfaces intersect the selected parent surfaces. Both internal are external sketches are displayed as sub nodes of the surface region on the Model Tree. You can edit a sketch using the Edit Definition command on the Model Tree or modify the values of the dimensions of a sketch using the Edit command.
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Creation of surface regions using cosmetic sketches is not supported from Wildfire 5.0 onwards. Cosmetic sketches used to create surface regions in previous releases are converted to internal sketches.
Split by chain
You can use a chain of curves or edges to define the contours of a surface. The boundary curve or chain must lie on the surface that you want to split. If the curve is at some offset distance from the parent surface, Creo Simulate does not create the surface region.
Surface regions can be created using mirrored sketches using the Split by chain method. The mirrored sketch is treated as a separate curve while creating the surface region.