General questions about Fluent

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  • Last Post 20 February 2019
Peace posted this 18 February 2019

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.

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abenhadj posted this 18 February 2019

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?

Best regards,

Amine

Peace posted this 18 February 2019

The ISO-surface in Fluent? Or later at the CFD-Post? 

I tried to create a report with the vertex option under reports.

 

abenhadj posted this 18 February 2019

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.

Best regards,

Amine

Peace posted this 18 February 2019

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

rwoolhou posted this 18 February 2019

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. 

Peace posted this 19 February 2019

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.

 

rwoolhou posted this 19 February 2019

You mean the numerical beach effect? 

Peace posted this 19 February 2019

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.

 

rwoolhou posted this 20 February 2019

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? 

 

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