Achieving high damping and stiffness is challenging in common materials because of their inter-dependent scaling. Controlling extreme mechanical waves requires synergistically enhanced damping and stiffness. We demonstrate superior damping and stiffness in vertically aligned carbon nanotube (VACNT) foams that are also independently controllable by exploiting their synthesis-tailored structural hierarchy and structural gradients. They exhibit frequency- and amplitude-dependent responses with dramatically tunable dynamic stiffness while maintaining constant damping.
One of our studies on linear and nonlinear non-Hermitian metamaterials has been published on the recent special issue of the Journal of the Acoustical Society of America: Non-Reciprocal and Topological Wave Phenomena in Acoustics.
A “flutter machine” is introduced for the investigation of a singular interface between the classical and reversible Hopf bifurcations that is theoretically predicted to be generic in nonconservative reversible systems with vanishing dissipation. In particular, such a singular interface exists for the Pflüger viscoelastic column moving in a resistive medium, which is proven by means of the perturbation theory of multiple eigenvalues with the Jordan block.
It addresses the problem of finding the dynamic cyclic response of mechanical systems experiencing dry friction with a particular focus on the influence of varying normal and tangential loads. I first start from a single degree of freedom model and gradually increase the complexity of the system. In the last chapter I address a system with 12 degrees of freedom which shows localized vibration states, that are very similar to solutions known in other physics fields like optics and fluid dynamics.
This monograph gives a complete overview on the subject of nonconservative stability from the modern point of view. Relevant mathematical concepts are presented, as well as rigorous stability results and numerous classical and contemporary examples from mechanics and physics.
I want to find the material damping of polymer material through ansys, Is it possible to find the damping of a material damping by using ansys. In the experimental work the polymer material perspex is used in which 9 layers of perspex material are mounted on milling machine bed and machining is done along with work piece material to reduce the vibration and to found out the damping. How this can be analysed in ansys and which models can be used for this. Many layers are stacked one upon the other and damping has to be found out.How this modelling can be done.
Carbon nanotubes as strong fibers in CNT-composites are subjected to large deformations in radial direction. They provide strength as well as structural damping in the composite. Despite being strong in the axial direction, CNTs are rather soft in the radial direction.
Recent comments