Water-sediment interface condition in FLUENT?

- February 24, 2022 at 12:50 am
  
  xing
  Subscriber
- February 24, 2022 at 3:25 pm
  
  Rob
  Forum Moderator
  
  Are you expecting to move the sediment, or just see what the water does? For the latter I'd expect an interior surface. If the free surface isn't disturbed I'd also look to run this single phase. If you are disturbing the sediment then it's a bit more complicated.
- February 24, 2022 at 11:05 pm
  
  xing
  Subscriber
  
  Yes, the sediment is immobile and has a uniform permeability. We just supply viscous resistance to the sediment and allow surface water to flow into and out of it to rejoin the surface stream, which occurs due to pressure variations caused by the redd surface. Because we are also considering the influence of free surface fluctuation, there should be a two-phase model. In this case, what would be the proper condition to apply to the water-sediment interface, we wonder?
  1) Is it sufficient to simply assign an interface, or would you have any other treatment for the interface?
  2) Is it possible to set any interface thickness? If so, how to do it in Fluent?
  3) Is there a method we can impose only a normal flux into sediment via a water-sediment interface?