Flexible Beam Impact Transient Wave Propagation In Dynamic Substructure

Though there has been the certain research achievement in the impact of flexible beam at present, the achievement of its transient response and transient wave propagation is not complete. Therefore, the main research of this text is the substructure technique which is the transient response and transient wave propagation in impact of flexible beam.According to the basis suppose of the Bernoulli-Euler beam, the text builds up the model which the free end part of a flexible beam is impacted by a rigid ball. Firstly, the flexible beam is discretised by the substructure technique. Secondly, the equation is built up, and it is solved with the synthetic substructure technique of the fixed-interface mode. The text gives an example. It is solved with the different discretization methods. Then, according to the solution, the text makes an in-depth analysis, and discusses the influence of the different discretization methods and the number of substructure modes in results. Finally, it obtains the more reasonable discretization methods and the number of substructure modes to reflect the process of impact the more precisely and the more effectively.The text researches in detail the process which the free end part of a flexible beam is impacted by a rigid ball. It calculates the response of the impact force. the response of the deflection, the velocity, the corn move and corn speed and so on, whose characteristic and regulation may analyze the impaction's transient mechanics behavior.Finally, this text firstly applies dynamic substructure technique research on the dissemination of the transient bending wave, which a flexible beam is impacted by a rigid mass during impact. It contains the characteristic of the flexible beam's stress wave, the displacement wave, the velocity wave, the corn move and corn speed wave, shear force wave and so on. They may accurately describe the dispersion's characteristic of the bending wave. The result expresses the dynamic substructure technique may portrays propagation mechanism of the transient stress along the flexible beam during impact. The dynamic substructure technique has the ability comparing with the theoretical analysis method, which could analyze flexible complicated structure. It is more efficient than the dynamic finite element method. In addition, the method can save the computer resource. Therefore; the dynamic substructure technique may have great potential to research the impact of the flexible structures and transient wave's dissemination which is stimulated by impact.