Phononic band gap design in honeycomb lattice with combinations of auxetic and conventional core

Mukherjee, Sushovan and Scarpa, Fabrizio and Gopalakrishnan, S (2016) Phononic band gap design in honeycomb lattice with combinations of auxetic and conventional core. In: SMART MATERIALS AND STRUCTURES, 25 (5).

PDF Sma_Mat_Str_25-5_054011_2016.pdf - Published Version Restricted to Registered users only Download (3MB) | Request a copy

Abstract

We present a novel design of a honeycomb lattice geometry that uses a seamless combination of conventional and auxetic cores, i.e. elements showing positive and negative Poisson's ratio. The design is aimed at tuning and improving the band structure of periodic cellular structures. The proposed cellular configurations show a significantly wide band gap at much lower frequencies compared to their pure counterparts, while still retaining their major dynamic features. Different topologies involving both auxetic inclusions in a conventional lattice and conversely hexagonal cellular inclusions in auxetic butterfly lattices are presented. For all these cases the impact of the varying degree of auxeticity on the band structure is evaluated. The proposed cellular designs may offer significant advantages in tuning high-frequency bandgap behaviour, which is relevant to phononics applications. The configurations shown in this paper may be made iso-volumetric and iso-weight to a given regular hexagonal topology, making possible to adapt the hybrid lattices to existing sandwich structures with fixed dimensions and weights. This work also features a comparative study of the wave speeds corresponding to different configurations vis-a vis those of a regular honeycomb to highlight the superior behaviour of the combined hybrid lattice.

Item Type:	Journal Article
Publication:	SMART MATERIALS AND STRUCTURES
Publisher:	IOP PUBLISHING LTD
Additional Information:	Copy right for this article belongs to the IOP PUBLISHING LTD, TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND
Keywords:	periodic structures; auxetic materials; band structure; negative Poisson's ratio; wave propagation; spectral finite element
Department/Centre:	Division of Mechanical Sciences > Aerospace Engineering(Formerly Aeronautical Engineering)
Date Deposited:	16 Jun 2016 04:48
Last Modified:	16 Jun 2016 04:48
URI:	http://eprints.iisc.ac.in/id/eprint/53973

Actions (login required)

View Item