Hello again gurus...
I just got some rather disappointing news about damping andcosmos/M. "Composite material damping" specified when I use theDAMP material property assigns the value of damping ratio for thematerial. It isn't the damping coefficient, "c" that is in all thestructural dynamics books. That is a bummer. It means I can getwhatever response I want out of the simulation, not a prediction ofreal life response. damping should depend on the mass and stiffnessof the system in the form of damping = 1/root(k*m) for a singledegree of freedom. So if I use a heavier mass, the response atresonance should increase due to damping decreasing. That doesn'thappen unless I also decrease DAMP when I increase density. Theresponse turns out to be identical for increased density and DAMPheld constant.
I know some rules of thumb for damping like more damping for densermaterials, etc. Please tell all of your rules of thumb you use tochange damping for a changing elastic modulus or density(or both).I know that modal damping is a very difficult property to simulateunless you can physically measure the system. But we wouldn't beusing FEA then, if we already had the system.SolidworksSimulation
I just got some rather disappointing news about damping andcosmos/M. "Composite material damping" specified when I use theDAMP material property assigns the value of damping ratio for thematerial. It isn't the damping coefficient, "c" that is in all thestructural dynamics books. That is a bummer. It means I can getwhatever response I want out of the simulation, not a prediction ofreal life response. damping should depend on the mass and stiffnessof the system in the form of damping = 1/root(k*m) for a singledegree of freedom. So if I use a heavier mass, the response atresonance should increase due to damping decreasing. That doesn'thappen unless I also decrease DAMP when I increase density. Theresponse turns out to be identical for increased density and DAMPheld constant.
I know some rules of thumb for damping like more damping for densermaterials, etc. Please tell all of your rules of thumb you use tochange damping for a changing elastic modulus or density(or both).I know that modal damping is a very difficult property to simulateunless you can physically measure the system. But we wouldn't beusing FEA then, if we already had the system.SolidworksSimulation
