[noa]

My model is a 2D rectangular channel. I am able to move the upper and lower walls of the channel along Y axis (using UDF, DEFINE_GEOM). However, when I try to move these walls also in the X axis it says error.

Is it possible to move a wall along X and Y directions using UDF or any other method?

[Amir]

Hi,refer to:
http://www.cfd-online.com/Forums/fluent/84749-moving-wall-boundary-condition.html

[xrs333]

Moving along the wall surface itself should not be modeled with dynamic mesh, instead it may be simulated with boundary condition of the wall.

[noa]

I am using udf to move the upper and lower walls . I tried to move these walls along the X axis using boundary condition(using moving wall), but when I do that it just take the udf and ignore the boundary condition.

[noa]

Hi Amir,

I can't open this link you sent me.

[noa]

Thank you, I opened it.
However my 2D channel is expanding (which I already did) and moving along X axis. How do you do it both???

[Amir]

if you have a function of boundary nodes changes with time, you can do that with implementation of smoothing tool in dynamic mesh.

[dhu]

Hi,
I am new to CFD online and recently started working with fluent...can anybody help with my model of a liquid in rectangular tank which has a half-circular patch at its base of a second fluid? now I want to move the left and right wall opposite to each other (inwards) and see the effect on the second fluid...but with moving wall boundary condition along +ve and -ve xdirection,the resultant vectors doesn't show any such motions...
please suggest the boundary condition and the model that should be used in this case( I was using VOf)