I am currently truing to simulate dust particles entering a silo, similar to what S. Rani and Haeurt & Vogl, they used transient, 3D, Rosin-Rammler, RANS, second order upwind etc. I have created a silo and have added two particle injections so far which are very small. I did a coupled method with a time step of o1. I am encountering all kinds of problems, I have simplified the model and even turned the discrete phase off. The results aren't showing a lot of the dust concentration, I need the concentrations because I am trying to determine the lower explosive limit. I realise I am not putting many particles in but when I add more the computer crashes, freezes or says there is no memory. I am doing this on an engineering desktop too. Please help with any advice a lot depends on this.