General questions about Fluent

- February 18, 2019 at 8:55 am
  
  Peace
  Subscriber
  
  I am trying to create a plot overtime of my waterline elevation as I saw other people doing with the Vertex option but I am getting a straight line
  
  My mass flow chart at the inlet is perfectly fine and I do have wave propagation so I am thinking that I am probably doing something wrong in picking out variables.
  
  What should I use?
  
  Another question: Is there any way in Fluent to absorb waves at the end of the domain so as to not have my input waves affected by the reflected waves at the end of the domain?
  
  Thank you in advance.
- February 18, 2019 at 9:16 am
  
  DrAmine
  Ansys Employee
  
  Second part of your question: Yes either deploying numerical beach to dampen wave reflection or/and sponge zone (coarse mesh zone) to dampen reflection.
  
  First part: You need create a iso-surface of VOF=0.5 then clip that to a line (in 3D). What did you do?
- February 18, 2019 at 9:30 am
  
  Peace
  Subscriber
  
  The ISO-surface in Fluent? Or later at the CFD-Post?
  
  I tried to create a report with the vertex option under reports.
- February 18, 2019 at 9:56 am
  
  DrAmine
  Ansys Employee
  
  But which boundary or surface or line have you used for your report?
  
  I am talking about Fluent as I thought you are referring to post-processing in Fluent.
- February 18, 2019 at 10:04 am
  
  Peace
  Subscriber
  
  I tried a bunch so as to be sure that I tried everything before asking.
  
  I used the area of water I have, the freesurface (type interior ) line I have dividing the 2 phases and the inlet boundary.
  
  I did this in the calculation phase in fluent.
  
  Thanks again,
  
  Kindest Regards,
  
  Peace
- February 18, 2019 at 10:13 am
  
  Rob
  Forum Moderator
  
  The interior line doesn't affect the free surface, and also shouldn't move. Look at the free surface (plot iso surface of VOF=0.5) and compare that to the mesh (for reference). You need to then get the VOF height at a set position which is easily done in Fluent.
- February 19, 2019 at 4:32 pm
  
  Peace
  Subscriber
  
  Secondly is there any way in Fluent for active wave absorption. Essentially I would like to absorb waves travelling towards the velocity-inlet (wave generator).
  
  Thank you.
- February 19, 2019 at 4:59 pm
  
  Rob
  Forum Moderator
  
  You mean the numerical beach effect?
- February 19, 2019 at 5:48 pm
  
  Peace
  Subscriber
  
  What I need is for my inlet to "absorb" returning waves without interfering with my generated waves.
  
  I have just tried the Open Wave BC which looks like it produces a proper wave but I don't know if its inlet is able to absorb the returning waves.
  
  Also does Open Wave BC define the free-surface location as well as u,w components of velocity to produce the waves?
  
  Thanks again.
- February 20, 2019 at 11:41 am
  
  Rob
  Forum Moderator
  
  The inlet can't absorb the returning waves, they'll simply interact with the next one coming in. In a real system the wave generator is at one end of the system and a beach/weir arrangement is at the other to prevent the wave reflecting back down the system.
  
  Re the open channel: what does the manual say?