Discussion Forum

Ok, I'm a complete novice with the Structural mechanics module, but I agree it should be easy! Even if there isn't any angular momentum post-processing operation being made available to you somewhere (and I wouldn't be surprised if there is), you should still be able to define your own domain probe of type integral to compute the integral over the cross product of a vector from the origin and the velocity of a mass element, or: mass_density_rho times vector_r cross vector_v dVol. I just checked, and I found that components of linear velocity (if I read it correctly) in terms of (x,y,z) should be available to you in post-processing in this module as (solid.u_tX, solid.u_tY, and solid.u_tZ), and also there's the (scalar) mass density: solid.rho . Starting from those, you should be able to construct an appropriate cross product vector in terms of its three components and compute the approprate integrals (as domain probes, I suggest) of them yourself. Computing the angular velocity vector, of course, is even easier. For the physics formulas, if you don't already know them by heart, see any classical mechanics textbook, or simply scroll down the page at: https://en.wikipedia.org/wiki/Angular_momentum . Now, if you haven't used probes in Comsol Multiphysics before, you might want to read about them in the Help system and review some of the provided example applications. I hope that helps. Good luck.

Thanks, I'll definitely get acquainted with the post processing options and the probes and try it again!