[Gibson21]

I am looking at multiphase flow (air-water-sand) through a vertical pipe, I first started with a 0.5 metre pipe and successfully got this working. The inlet velocities of air water and sand were 5, 2.5 and 0.25 m/s respectively.

I now need to increase the pipe to 60 metres but i am having problems. Some of the simulations i have ran have converged but when i go into 'fluxes' to inspect the inlet and outlet it is showing that there is no sand or air in the outlet of the pipe and only water?

On scaling up to 60 metres is there any useful tips in any settings i may need to change within the setup to ensure the sand and air reach the outlet?

I am not the most experienced with ansys fluent so thanks in advance for any feedback!