Learning Forum

[SaurabhD]

Hi, 

I have two questions related to a simulation I am working on. It would be truly helpful if somebody can put some light on it. (Ansys Version - 19.2)

1. I am unable to access the "Momentum" part of the Wall boundary condition. I want to add "Contact Angle" and so need it but the options are not appearing at all. 

2. Is there any way I can let the solver decide the contact angle by its own instead of specifying a constant value. 

 

Thank You. 

[Rob]

Contact angle is for multiphase only (VOF with surface tension). What are you trying to do?

[SaurabhD]

Hello Sir, 

I am using Multiphase (VOF) model & have also defined the surface tension. 

My model is very simple. I have 5 cylinders and a closed environment (the defined rectangular box). They both are made of Aluminium. (Image 1)

Then by using the "Region" in the Fluent, I have defined a sphere which would act as my droplet falling on these cylinders. 

 

Problem 1: I am not understanding why are there so many "Zones" being defined in Fluent. Ideally there should have been only 7 at the maximum. 5 - Wall for each cylinder, 1 Solid for the Box and 1 for interior of the box. Any guidance with this would be of great help. 

 

Problem 2: The cylinders have been defined as "Interface". I don't know how to change that to Wall. 

 

Problem 3: The zone defined as wall have no option under the momentum tab. I wanted to set the wall to "No Motion" and also wanted to define the "Contact Angle". 

 

Thank you so much for the help. 

 

 

[Rob]

You need to create a multibody part or use share topology (DesignModeler & SpaceClaim respectively) to give a conformal mesh. That will remove all the interface zones. Contact angle is then set on the wall once you turn on surface tension & wall adhesion in the various panels.