Ice Slurry flow in pipe

Dear Nagi Elabbasi

I am currently trying to build a model for ice slurry flow in a pipe using mixture model laminar flow, with my interest in velocity, dispersed phase fraction distribution. i initially tried building the my model based on the dense suspension benchmark in-built model in comsol but i was came up with inconsistent initial values problem
so i tried using a model based on sedimentation model which was applied in the modelling of contaminant- removal from wastewater in secondary clarifier, and i "Failed to find consistent initial values. Last time step is not converged" keeps showing

Pls i would be grateful for any help

Thank you