open TELEMAC-MASCARET The mathematically superior suite of solvers

Hi all，

I have a problem in simulating sediment transport. The simulation always failed when I consider 2 classes sediment (diameters are 0.00075 and 0.00025). However, it is ok if I only consider 1 class seidment (0.00075 or 0.00025 are both OK). Who met the similar problem? thank you.