Help:Euler model with inmiscible fluid model
 

Need Help. (Fluent)

I'm using Euler model with inmiscible fluid model as multiphase model for modeling gas-liquid flow in tube, but when I calculating, of Courant Number is greater than 250 in the second iteration. The message is the following:

Error. Globar courant number is greater than 250.00 The
velocity field is probably diverging. Please check the solution
and reduce the time-step if necessary.
Error Objet: #f

I tried the following: reduce the time-step, reduce the inlet velocity of both the phases, but did not work.

Anyone knows how to setting model that does not happen??

I not using VOF model because it not fulfill my requirement.