FEAP User Forum

FEAP => Programming => Topic started by: weiyongtao on February 27, 2021, 12:21:32 AM

Title: what are meanings of arrays "gomev" and "gomex" in the subroutine "sbodyw"
Post by: weiyongtao on February 27, 2021, 12:21:32 AM

I guess the "gomex" store coordiantes of rotation center, and "gomev" is the unit vector of the rotation axis. Is it right?
Another questions, what meaning of ndfo(1), shflg and frotas in the file framf3d.f
Best regard.

Title: Re: what are meanings of arrays "gomev" and "gomex" in the subroutine "sbodyw"
Post by: Prof. R.L. Taylor on February 27, 2021, 11:14:49 AM

These are part of "global" values set in the routine ./program/pglobal.f

You need to learn how to trace back variables using 'find' or 'grep' depending on your operating system.

Title: Re: what are meanings of arrays "gomev" and "gomex" in the subroutine "sbodyw"
Post by: weiyongtao on February 27, 2021, 04:31:22 PM

Dear Prof. R. L. Taylor
Thanks for your reply.
I am converting the subroutine framf3d.f into C/C++ and I‘m closing to finish this work. But there are some details unclear to me. For example, the meanings  "ndfo(1)", "shflg" and "frotas" in the file framf3d.f, which are used when forming the lumped or consitent mass matrix.
According to the  Reference: A. Ibrahimbegovic and M. Al Mikdad, IJNME, [1998],Vol. 41, pp. 781-814,  the first order derivative of theta with respect to time is not the angular velocity. So for the beam model in framf3d.f,  what's meaning of ul(4:5,,4)? They are the time derivative of theta, or the angular velocity? Or for the subroutine extrfb, it return the array v1,Spatial rotaional velocity  at t_n+1, this v1 is the time derivative of theta, or the angular velocity?
Best regards.
Prof. Wei Yongtao
Sichuan Universtiy.

Title: Re: what are meanings of arrays "gomev" and "gomex" in the subroutine "sbodyw"
Post by: FEAP_Admin on February 27, 2021, 10:29:18 PM

Why are you interested to convert the subroutine to C/C++?

Title: Re: what are meanings of arrays "gomev" and "gomex" in the subroutine "sbodyw"
Post by: weiyongtao on February 27, 2021, 11:43:42 PM

I am used to develop codes  based on OOP. All my FEM codes are based on my OOPFEM frame. But my fem codes lack of a geometric nonlinear  beam element .