Loic Ivaldi
Ansys Employee
I would recommend to disable the mass scaling. If you think it's too time consuming you can increase the Time step factory factor (TSSFAC=0.8).
You can dig to the mes#### files to have details regarding the SPH neigbor particles. But you can try to set Initial Number of Neigbors = 300 or 500 instead of 150.
Last thing, you said "When the drill was moving, the nozzle simply broke off and deformed" meaning for my side your tool isn't rigid. If you're not concerned by the cutting tool make it rigid. And if you're interested in it well... for the first simulations, keep it rigid.