The distribution problem of generated particles

Hello everyone! I want the particles to be distributed in the cylinder.In the figure below, I have set a rectangularas an initial condition.But the generated particles go beyond the established geometry. How can i solve it?Thanks very much for your reply2

It is not an issue with particle generation, but with the mesh. First, make sure the geometry itself (stl file) is waterproof (verify there are no ignored facets when the file is read). Then you may need to adjust some cut cell settings, such as the snap tolerance or dot product tolerance.

Thank you for helping a new MFiX leaner! I’ve solved this problem according to your suggestion.