The radiate surface feature in SOLIDWORKS is a neat tool for creating surfaces that seem to radiate from a face on a solid body. With the radiate surface feature, the user can define a surface based on a split line on a surface and a corresponding flat face. Look at the rectangular profile shown below.
We can create a surface radiating on one of its side based on a split line. Create a plane offset from one of the faces.
On this plane, create a sketch of an irregularly shaped spline much like the one shown below.
Next, go to the command window and search for split line tool. SOLIDWORKS automatically identifies the current sketch as the sketch to be projected, and all you need to do is select the face on which the sketch is to be projected. Notice that you can select multiple faces.
Once this is done, you can see the split line form on the selected surface of the part.
Move to the surface tab and select the radiate surface feature.
SOLIDWORKS lets you choose the direction of the radiated surface and the edge of which the surface is to be radiated. With these two parameters set, you can click on the green marker to set up the surface.
The radiate surface feature works similar to the surface extrude feature, with the only advantage being that you can control the direction of extrusion of the surface for the radiate surface feature, unlike in surface extrusion where the extrusion is done normally to the surface containing the sketch. Also, the surface extrudes command can only work on sketches and not edges, and thus is not applicable in this particular scenario.