[David12]

Hello, I currently am simulating the rotation of a propeller in ANSYS (transient solver). I've used a UDF macro (DEFINE_ZONE_MOTION) to have my propeller cell zone to rotate at a constantly changing RPM. However, I'd like to be able to see the angular velocity values for each time step, and see it's graph. I don't see an option to graph angular velocity in the report definitions, nor could I figure out how to do it through another UDF or expression. Can anybody help me figure out how to extract the angular velocity? Thank you, I'd appreciate it alot.

[AlexanderZ]

this is definition of DEFINE_ZONE_MOTION

DEFINE_ZONE_MOTION (name, omega, axis, origin, velocity, time, dtime)

omega here is angular velocity, you may write it to file on each timestep

[David12]

Originally Posted by AlexanderZ

this is definition of DEFINE_ZONE_MOTION

DEFINE_ZONE_MOTION (name, omega, axis, origin, velocity, time, dtime)

omega here is angular velocity, you may write it to file on each timestep

Hi AlexanderZ, thank you for your advice, I did exactly just that and was able to export the data to a text file when the simulation runs. I do now have a different problem now since the data is posted twice in the data file as if function was ran twice. I am currently trying to solve that and if you had any advice on that, I'd love it hear it.

[AlexanderZ]

#include "udf.h"
static int last_ts = -1;

DEFINE_ZONE_MOTION (name, omega, axis, origin, velocity, time, dtime)
{
int curr_ts;

curr_ts = N_TIME;
if (last_ts != curr_ts)
{
last_ts = curr_ts;
***your code***
}
}