Crashworthiness Analysis Of Composite Waved Beams

Composite absorbing energy element is an important part of helicopter absorbing energy buffer system, playing a role of protecting staff during the crash. So the reasonable choice of composite absorbing energy element is more energy absorbing element is an urgent requirement for the helicopter energy absorbing system design.In this paper, the stability of waved beams is studied to analyze the necessity of the weak link in triggering asymptotically stable crushing of composite waved beam under the impact. Qualitatively analyze the influence law of the angular value of weak links force theoretically, and establish the finite element model of the weak link to study the peak value of the shock load of various angle values of the weak links under impact. The results show that the weak links are important for asymptotically stable crushing of the whole waved beam and reasonable angle value of the weak link can effectively reduce the peak load of the impact. According to the theoretical analysis and finite element simulation results, the equivalent scheme of the weakness is established for the structure analysis.Established the long single wave, the short single wave and the three wave composite waved beams structure finite element model, written material subroutine VUMAT to define material properties and failure criteria for reducing the layer stiffness of the broken composite materials, and removing the complete failure cell. Used the cohesive element in the corrugated web beam to realize composite delamination failure mode, more truly simulating the micro damage of wave composite waved beams under impact. The comparative analysis of the simulation results and the experimental results verify the rationality and effectiveness of the model.Test the composite waved beams with two ways of static loading and impact loading, and research the failure mode of composite corrugated beam structure through the experiment. The results show that the stability problems of long single beam structure, and the three wave structure has good energy absorption ability.