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Convert transient case to steady state case

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Old   July 29, 2021, 04:44
Default Convert transient case to steady state case
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I'm working on simulating kinematics of insect wing flapping and I wrote a UDF for its transient kinematics which works fairly well. The problem is that I need to actually rework the simulation as a steady state case for my final results. My current code has a time component which does not get processed by Fluent as the case is steady state, as you may see below:

/* flap.c */
/* UDF for specifying a simple harmonic motion*/
/* */

#include "udf.h"
#define Freq 0.1
#define angular_freq 2.0*M_PI*Freq
#define tetmax -45.0*M_PI/180

DEFINE_CG_MOTION(shm, dt, cg_vel, cg_omega, time, dtime)
real omega;
omega = tetmax*angular_freq*cos(angular_freq*time); /* rotational speed about axis*/

cg_vel[0] = 0.0075 * sin(3.1415927 * time / 5.);
cg_vel[1] = 0.0;
cg_vel[2] = 0.0;

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

I need to know how I can change this code so it works in a steady state case as well.
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Old   July 29, 2021, 05:41
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AlexanderZ will become famous soon enoughAlexanderZ will become famous soon enough
motion itself implies something transient, isn't it?

if you need steady state simulation on specific configuration of domain, you may :
1. prepare this mesh from the very beginning and run it as steady state
2. or stop your transient simulation at specific moment

probably you have special knd of problem, which I don't fully understand
best regards

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