Bandgap Modulation Of Zigzag Honeycomb Rubber Soft Phononic Crystals

Phononic crystal(PC)is an artificial periodic structure which has acoustic/elastic bandgaps.It has potential applications in vibration control,noise suppression,waveguides,sensors and so on.The zigzag honeycomb PC is structured by introducing the zigzag shape with chiral symmetry into the common honeycomb PC.The zigzag honeycomb PC has a lot of characteristics including low porosity,light quality and so on,just like honeycomb PC.And it can produce bandgaps at lower frequencies because of local resonance of the zigzag shape,which means it has potential engineering applications.As is known to all,the bandgap modulation of the PC has been a core issue of the wave problem,and a great deal of research has been done in this respect.However,in practice,how to adjust the bandgaps of the formed PC is still a problem.Because soft material structure is easy to deform when the load is applied on the structure,we can use this property to adjust the bandgap of the formed PC.In this paper,the Python language combined with the commercial finite element software ABAQUS is used to study the bandgap modulation of the rubber zigzag honeycomb PC under tensile and compressive load.For the given load,the influences of geometric parameters on the bandgaps are discussed.And we also have the experimental studies in the case of the tensile load.The main contents and results of this paper include:1.The effects of the tensile load to the bandgaps of soft common zigzag honeycomb structure are studied.The influences of the structure symmetry,geometric parameters and value of tensile load on the bandgaps are discussed and verified by experiments.The results show that the bandwidth of bandgaps can be tuned well by the tensile load.But there is almost no influence on the positions of bandgaps.And there is almost no new bandgap is generated.2.The buckling mode of the soft common zigzag honeycomb PC is studied.The result shows that there is just global buckling occurred.Then different improved methods are tried to make sure that the local buckling can occur.For the soft common zigzag honeycomb PC,the methods of reducing the branch ends and replacing straight branches by curve branches can change the buckling mode effectively,so that the local buckling can occur.For different methods,the change of the structures is different,so does the critical strain.3.The effects of compressive load and buckling to the bandgaps of the improved rubber zigzag honeycomb PC are studied.The influences of the improved methods,the compressive load,the geometric parameters and the reduction ratios of the end of the branch on the bandgaps are discussed.The results show that the effect of compressive load to the bandgaps are larger than that of the tensile load.For the straight branch PC,the bandgaps appeared in the pre-buckling period can be tuned well by the compressive load.While for the curve branch PC,it is the bandgaps generated in the post-buckling period that can be tuned well.The compressive load can adjust not only the width but also the positions of the bandgaps,and can generate new bandgaps.For the structures with different improved methods,geometric parameters or reduction ratios of the end of the branch,the influences of the compressive load on bandgaps are slightly different.