BrokenPipeError when use multiprocessing pool in FEM╳DEM

Dear all,

In the FEM╳DEM simulation(/examples/FEM╳DEM/triaxialRough.py), I met "BrokenPipeError: [Errno 32] Broken pipe" when use multiprocessing pool in python(due to a mass of RVE packings).

My domain of simulation is 3D. I found that the multiprocessing pool work successful when my RVE packing is small enough, but when I use an RVE of more than 1000 particles(mean radius=0.005), the error code will appear (BrokenPipeError: [Errno 32] Broken pipe)and the simulation would stop.

With my poor understanding of multiprocessing library, I guess this is probably due to too many particles leading to too much data. In addition, I use cohesive particle model in RVEpacking.

Could anyone help me with this problem?
Thank you for attention