【作者】 邹华；

【导师】 尹晓春；

【作者基本信息】 南京理工大学 ， 固体力学， 2002， 硕士

【摘要】 结构碰撞问题，在实际工程中经常可以遇到，是十分重要的工程结构动态强度问题。多次内撞击会造成结构的疲劳破坏，零部件的磨损，振动和噪声等。因此，研究结构多次撞击问题具有重要的理论和工程应用价值。 本文利用瞬态波函数的特征函数展开法推导出了单柱结构、单梁结构和梁—柱结构瞬态波传播的理论公式。通过数值计算，得出了比较理想的结果，验证了应力边界条件，对Eringen和Suhubi的方法作出了合理的修正，并指出在工程振动分析应加以注意的问题。 本文针对工程中阀门与阀座的撞击问题，建立了解决此问题的力学模型，即Bernoulli-Euler梁和弹性柱的碰撞模型。通过对材料不同的梁和柱多次内撞击的理论分析和数值计算，给出了完整的梁—柱结构多次内撞击的理论和数值分析方法。由计算得出的位移、质点速度、界面压力函数等可以看出，本文给出的理论和数值分析方法是实用和可靠的。更多还原

【Abstract】 The collisions are frequently encountered in mechanic structures, resulting in the fatigue, wear and vibrations of components causing noise. It is important to study the collision phenomenon in theory and practical applications.By the use of the eigenfunctions, the formulas of the propagation of the transient wave along rod, beam and beam-rod structures are derived in the present paper. The numerical results of these formulas are quite reliable and verified by the boundary conditions. Hence, the approximate formula obtained by Eringen and Suhubi are modified reasonably, and some questions of the use of eigenfunction expansions in practical applications are pointed out.In order to study the collisions between the valve reed and the valve seat, this paper has developed a mechanics model based on the theory of Bernoulli-Euler beam. The exact solution theory analysis and numerical simulation are given for the description of the phenomenon of the multiple collisions between the beam and the rod. The results of the displacement, velocity, and the collision pressure show that the present method is functional and reliable.更多还原