[quarkz]

Hi,

I am working on a 6dof problem whereby the body is allowed to pitch up due to external forces.

I need to know the pitch up angle at each time step, so that I can do some mesh manipulation at each time step. I can thinnk of a few solutions:

1. modify OF codes somewhere to get the orientation tensor. i read something similar here:

How to access to the solid body motion state from a custom interDyMFoam.C ?

but being a Fortran coder, I have a hard time understanding.

2. If I know the position of a point mesh at a particular time step, and also its initial position at t = 0, I can find the angle the body has pitched thru dot product and the center of rotation. i can access a mesh pt from p0_[iter], which has the mesh position at the current time step. But I can't access the mesh position at t=0 and i do not know how to store that value for later time step usage. I need to know how to store a scalar variable as global which value will not change as time proceeds.

3. OF output will give the orientation matrix at each time step. So if I can capture that output, I can use it to calculate the pitch. There are some posts which extract variables info from log. So if I can run such codes using systemCall, I can extract the info as a file at the end of a timestep. Then read in the file data in the next time step.

Hope someone can help. Thanks!