Dr Gyani Shankar Sharma
Lecturer

Dr Gyani Shankar Sharma

Engineering
Mechanical and Manufacturing Engineering

I am a Lecturer in the School of Mechanical and Manufacturing Engineering at UNSW Sydney. I received a PhD from UNSW Sydney and an MS from the Indian Institute of Technology Madras. My research interests include wave propagation in complex media, metamaterials, acoustics, noise control, vibration, finite element methods, uncertainty analysis and optimisation. I currently teach finite element methods and fundamentals of acoustics and noise. I have two years of industrial experience as an engineer at Eaton Corporation, a Fortune 500 company.

Phone
+61 2 9348 0690
Location
Room 311E, Level 3, Ainsworth Building, UNSW Sydney, Kensington
  • Journal articles | 2020
    Sharma GS; Faverjon B; Dureisseix D; Skvortsov A; MacGillivray I; Audoly C; Kessissoglou N, 2020, 'Acoustic performance of a periodically voided viscoelastic medium with uncertainty in design parameters', Journal of Vibration and Acoustics: Transactions of the ASME, vol. 142, http://dx.doi.org/10.1115/1.4046859
    Journal articles | 2020
    Sharma GS; Skvortsov A; MacGillivray I; Kessissoglou N, 2020, 'On superscattering of sound waves by a lattice of disk-shaped cavities in a soft material', Applied Physics Letters, vol. 116, http://dx.doi.org/10.1063/1.5130695
    Journal articles | 2020
    Sharma GS; Skvortsov A; MacGillivray I; Kessissoglou N, 2020, 'Sound scattering by a bubble metasurface', Physical Review B: Condensed Matter and Materials Physics, vol. 102, http://dx.doi.org/10.1103/PhysRevB.102.214308
    Journal articles | 2019
    Sharma GS; Skvortsov A; MacGillivray I; Kessissoglou N, 2019, 'Sound absorption by rubber coatings with periodic voids and hard inclusions', Applied Acoustics, vol. 143, pp. 200 - 210, http://dx.doi.org/10.1016/j.apacoust.2018.09.003
    Journal articles | 2019
    Skvortsov A; MacGillivray I; Sharma G; Kessissoglou N, 2019, 'Sound scattering by a lattice of resonant inclusions in a soft medium', Physical Review E, vol. 99, pp. 063006 - 063006, http://dx.doi.org/10.1103/PhysRevE.99.063006
    Journal articles | 2017
    Sharma GS; Skvortsov A; MacGillivray I; Kessissoglou N, 2017, 'Acoustic performance of gratings of cylindrical voids in a soft elastic medium with a steel backing', Journal of the Acoustical Society of America, vol. 141, pp. 4694 - 4704, http://dx.doi.org/10.1121/1.4986941
    Journal articles | 2017
    Sharma GS; Skvortsov A; MacGillivray I; Kessissoglou N, 2017, 'Sound transmission through a periodically voided soft elastic medium submerged in water', Wave Motion, vol. 70, pp. 101 - 112, http://dx.doi.org/10.1016/j.wavemoti.2016.10.006

Course coordinator award by Arc@UNSW

The overarching aim of my research is to develop noise prediction tools and mitigation strategies. My current research activities are summarised below:

  • Acoustic characterisation of metamaterials: Acoustic metamaterials are composite media comprising resonant inclusions arranged periodically in a host material. An underwater application of acoustic metamaterials is an anechoic coating on marine vessels to reduce the transmission of onboard machinery noise in the ambient marine environment as well as to absorb external acoustic waves. I have developed significant analytical and numerical capabilities to predict the acoustic performance of soft media embedded with voided and/or hard inclusions. My analytical approach is based on homogenisation, which is a powerful method to model an inhomogeneous structure as a homogeneous medium with effective properties. The analytical models employ analogies between disciplines such as acoustics, fluid dynamics and electrostatics. I have expertise in multiphysics finite element analysis, which I use to validate the analytical models.
  • Marine vessels covered with acoustic metamaterials: While acoustic metamaterials have been widely studied in the literature, previous work has mainly focussed on their acoustic characterisation using a planar array of inclusions in a host medium. The external hull of a marine vessel can be approximated as a cylindrical shell for its acoustic characteristics. This project integrated these two fields and developed a fully analytical framework of a cylindrical shell coated with an acoustic metamaterial. 
  • Uncertainty quantification in acoustic metamaterials: Uncertainties are inevitable in design parameters of acoustic metamaterials arising from the manufacturing process and inhomogeneity of material properties. I have developed stochastic models based on nonintrusive polynomial chaos expansion theory and Monte Carlo simulations to investigate uncertainty in the material and geometric properties of metamaterials on its acoustic performance. 
  • Sound radiation from a submerged hull near free sea surface: This project developed analytical and numerical tools to predict the sound radiation from a submarine hull submerged in water near the free sea surface. 
  • Novel environmental noise control strategies: I demonstrated a novel concept of local noise control along specific receiver directions by controlling the directivity of the radiated or transmitted noise. This approach is particularly useful for practical low frequency noise where global noise control is difficult to attain. The directivity pattern of the radiated or transmitted noise was controlled by attaching a lumped mass to the structure. The mass location to minimize sound pressure in a target direction was obtained using an optimization technique.

 

My collaborators: 

  • UNSW Sydney: Prof Nicole Kessissoglou, Dr Daniel Eggler and Prof Zhongxiao Peng
  • Defence Science and Technology Melbourne: Dr Alex Skvortsov and Dr Ian MacGillivray
  • INSA Lyon: A/Prof Laurent Maxit, A/Prof Beatrice Faverjon and Prof David Dureisseix
  • Naval Group Research: Dr Christian Audoly and Dr Valentin Meyer
  • University of Texas at Austin: A/Prof Michael Haberman
  • Kansai University: Prof Masahiro Toyoda
  • Indian Institute of Technology Madras: A/Prof Abhijit Sarkar

My Research Supervision

I am currently supervising the following PhD students.

Cikai Lin

Christopher Levin

Abhinav Konchery

Karthik Modur

My Teaching

In Terms 1 and 3, I convene MMAN4410 Finite Element Methods to 3rd and 4th year undergraduate students and postgraduate students. In Term 2, I teach MECH9325 to postgraduate and 4th year undergraduate students. In the past, I have taught advanced vibrations (4th year undergraduate), engineering mechanics (2nd year undergraduate), mechanical design (2nd year undergraduate), computer-aided design (2nd year undergraduate), engineering drawing (1st year undergraduate) and introduction to aircraft engineering (1st year undergraduate).

My courses have significant research-based components, digital learning modules and strong industry engagement. My combined industrial and academic experience enables me to effectively interlink theory and practice in my courses.