Repost:Fiber network with preffered orientation

Submitted by SHUBHAM AGARWAL on Wed, 12/09/2020 - 20:57

Hello
So far, i am able to generate fibers in random orientation using LIGGGHTS-flexible fibers.
However I wish to generate fibers with a preferred orientation, i.e. fiber crientation should follow a probability distribution of the form: f(theta)= 1/pi -A*cos(2theta). Whare A is a user defined parameter (=0 for random distribution).
Is there a way to implement above in liggghts

Thanks
Shubham

Forums:

SHUBHAM AGARWAL | Thu, 01/28/2021 - 13:32

Just reposting an old question

Thanks

mschramm | Thu, 01/28/2021 - 18:36

Hello,
Unfortunately, the only ways that are currently available to set the orientation of a particle template are:
random = randomize rotational orientation
template = use orientation from particle template
constant = use constant quaternion for orientation
The clean way...
You would need to add code to implement user supplied functions to alter the orientation.

The not so dirty way...
To get around this, you could use an external program to create N templates that range the distribution that you want and then assign appropriate probabilities to match your distribution.

The dirty way
You could always hardcode the pdf into the insert/pack function and recompile/add extra parameter to change the user supplied value.

SHUBHAM AGARWAL | Fri, 02/26/2021 - 20:37

Thanks a lot
Is there a place where I can find the format for implementing the user defined template (the clean way :))

Shubham