[hobing]

hi all.

I'm using a hexahedral volume, dT = 0.000016667s, each time step 0.1 deg rotation
All faces adjacent to the rotation domain are interfaces.
I'm trying to analyze a coaxial inverting propeller, but I'm having a bit of a problem.
The domain proceeds as front blade volume > stationary volume > rear blade volume, and the front and rear rotate at the same speed and in different directions.

Problem
1. There seems to be a mesh regeneration error when two forward and backward rotation domains rotate over time, so a negative volume is created and the calculation does not proceed

what i did
1. Check the geometry
2. Check the volume
3. Check boundary conditions
( Cell > MeshMotion , Interface Periodic Rotation , Rotate on Walls Created by the Interface )
4. Dynamic mesh

What else can I do?

Oh, by the way, the side of the front blade and the rear blade is the square Mesh