A modal approach to modeling spatially distributed vibration energy dissipation.

Segalman, Daniel Joseph

关键词: AMPLITUDES;    APPROXIMATIONS;    DAMPING;    ENERGY LOSSES;    FLAVOR MODEL;    FRICTION;    OSCILLATION MODES;    PRESERVATION;    SIMULATION;   

DOI  :  10.2172/993326
RP-ID  :  SAND2010-4763
PID  :  OSTI ID: 993326
Others  :  TRN: US1008073

学科分类：物理（综合）

美国|英语

来源: SciTech Connect

【 摘 要 】

The nonlinear behavior of mechanical joints is a confounding element in modeling the dynamic response of structures. Though there has been some progress in recent years in modeling individual joints, modeling the full structure with myriad frictional interfaces has remained an obstinate challenge. A strategy is suggested for structural dynamics modeling that can account for the combined effect of interface friction distributed spatially about the structure. This approach accommodates the following observations: (1) At small to modest amplitudes, the nonlinearity of jointed structures is manifest primarily in the energy dissipation - visible as vibration damping; (2) Correspondingly, measured vibration modes do not change significantly with amplitude; and (3) Significant coupling among the modes does not appear to result at modest amplitudes. The mathematical approach presented here postulates the preservation of linear modes and invests all the nonlinearity in the evolution of the modal coordinates. The constitutive form selected is one that works well in modeling spatially discrete joints. When compared against a mathematical truth model, the distributed dissipation approximation performs well.