[Majid Zarif]

Hi Every body
I want to simulate this problem in fluent by dynamic mesh ,PLAESE help me how to set the dynamic mesh settings? and ...
How can I set UDF to the motion of train in this problem?
Thanks
This is the link of problem....:
https://www.dropbox.com/s/wv8mg77pyi...unnel.jpg?dl=0

[vasava]

You could use DEFINE_CG_MOTION macro. See the following example

DEFINE_CG_MOTION(butterfly_flex_UDF, dt, cg_vel, cg_omega, time, dtime)
{
  cg_vel[0] = 0.0; //X-velocity
  cg_vel[1] = 0.0; //Y-velocity
  cg_vel[2] = 0.0; //Z-velocity

  cg_omega[0] = 0.0;
  cg_omega[1] = 0.0;
  cg_omega[2] = 0.0;
}

[Majid Zarif]

Originally Posted by vasava

You could use DEFINE_CG_MOTION macro. See the following example

DEFINE_CG_MOTION(butterfly_flex_UDF, dt, cg_vel, cg_omega, time, dtime)
{
  cg_vel[0] = 0.0; //X-velocity
  cg_vel[1] = 0.0; //Y-velocity
  cg_vel[2] = 0.0; //Z-velocity

  cg_omega[0] = 0.0;
  cg_omega[1] = 0.0;
  cg_omega[2] = 0.0;
}

thanks for your reply
As you said I should use this code if I want to move in X-direction with velocity of 0.5m/s?
#include "udf.h"

DEFINE_CG_MOTION(Train_Motion, dt, cg_vel, cg_omega, time, dtime)
{
cg_vel[0] = 0.50; //X-velocity
}

[vasava]

Yes. However you must also check some tutorial for mesh motion. You have such a large problem (in terms of mesh size) at hand. The mesh motion will make it even more challenging.

Also in my opinion simulating the train entering and leaving the domain will also be another challenge. I have tried such an example but I did not have any success with it.

[Majid Zarif]

Originally Posted by vasava

Yes. However you must also check some tutorial for mesh motion. You have such a large problem (in terms of mesh size) at hand. The mesh motion will make it even more challenging.

Also in my opinion simulating the train entering and leaving the domain will also be another challenge. I have tried such an example but I did not have any success with it.

As you said we don't have any solution?!
Is the way of changing CG motion is the solution?I tried it the fluent responded that "considering no motion"!