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Oscillating of Interface in VOF method

Hi
I want to use fluent to simulate the motion of a slug through a 2D channel.
I used
-explicit VOF method
-pressure-velocity Coupling= SIMPLE SPATIAL DISCRETIZATION
-Gradient= least Squares cell based
-Pressure= Presto
-Momentum= Second Order Upwind
-VOlume Fraction=Geo-Reconstruct

I enable Surface Tension force and wall adhesion. I adjust the value of contact angle and surface tension equal to 135 degree and 0.47.
Any other force is not applied to the slug. First I just want to study the performance of fluent on simulation of two phase flow.
When I run fluent, I find out the interface of slug is oscillating and the value of contact angle is not fixed equal to 135 degree.
How can I get ride of this oscillating?

Thanks in advance :)

Can you post a picture illustrates the interface motion this will give best understanding for your problem and give more chances to answered it?

kbaker

Quote:

Originally Posted by amir.mofakham (Post 420368)

Hi
I want to use fluent to simulate the motion of a slug through a 2D channel.
I used
-explicit VOF method
-pressure-velocity Coupling= SIMPLE

SPATIAL DISCRETIZATION
-Gradient= least Squares cell based
-Pressure= Presto
-Momentum= Second Order Upwind
-VOlume Fraction=Geo-Reconstruct

I enable Surface Tension force and wall adhesion. I adjust the value of contact angle and surface tension equal to 135 degree and 0.47.
Any other force is not applied to the slug. First I just want to study the performance of fluent on simulation of two phase flow.
When I run fluent, I find out the interface of slug is oscillating and the value of contact angle is not fixed equal to 135 degree.
How can I get ride of this oscillating?

Thanks in advance :)

Quote:

Originally Posted by kbaker (Post 420460)

Can you post a picture illustrates the interface motion this will give best understanding for your problem and give more chances to answered it?

kbaker

Hi kbaker
Thank you for your attention.
I attached a picture. I hope this picture is clear to show my meaning.

Hey as I see from your image this type of flow is not slug. The water region just compressed and expands but why the water not move down the channel? what prevent it from moving?