Meshing- Transient Motor

[sfsalharthi1]

Hi all, I’m running a 3D Maxwell Transient simulation of an electrical motor (geometry is inherently 3D, so 2D is not an option). My model includes PMs + rotor steel, band (motion), outer/inner regions, stator region ,stator steel, coils. My main issue is mesh quality / stability: I’ve tried multiple meshes but I still see noise and extra harmonics in results (e.g., torque / back-EMF). I’m not sure if this is expected physics/numerics or if my meshing approach is wrong. Right now my “quick” approach is basically Length Based → Inside Selection applied to most parts with ~5 mm. What I’m looking for (practical guidance): Mesh seeding strategy per part Where do you usually apply Length Based on faces vs inside volumes (PMs, rotor steel, stator teeth/yoke, coils, regions)? Any advice on using surface approximation settings vs just length-based refinement? Meshing for rotating motion / band setup For motion, I understand the moving parts should be isolated with a band, and the re-meshed region is inside the band each timestep. What’s the best practice for the band mesh operation and for stabilizing torque/force results (to avoid mesh-driven noise)? Airgap modeling question (band + air regions) Do I need an explicit vacuum “airgap volume” object? In my geometry, the band sits in ~1/3 of the airgap and the stator-side region is ~1/3; the remaining ~1/3 is currently just “empty space”. If I create an airgap volume it will touch/overlap the band, so I left it. Is this a problem, and what’s the recommended way to partition the airgap volumes around the band? If helpful, I can share screenshots of the band/airgap layout + current mesh settings.