title: Broadband sound blocking in phononic crystals with rotationally symmetric inclusions.
abstract: This paper investigates the feasibility of broadband sound blocking with rotationally symmetric extensible inclusions introduced in phononic crystals. By varying the size of four equally shaped inclusions gradually, the phononic crystal experiences remarkable changes in its band-stop properties, such as shifting/widening of multiple Bragg bandgaps and evolution to resonance gaps. Necessary extensions of the inclusions to block sound effectively can be determined for given incident frequencies by evaluating power transmission characteristics. By arraying finite dissimilar unit cells, the resulting phononic crystal exhibits broadband sound blocking from combinational effects of multiple Bragg scattering and local resonances even with small-numbered cells.
authors.affiliation: Institute of Advanced Machines and Design, Seoul National University, 1 Gwanak-ro, Gwanak-gu, 151-744 Seoul, Republic of Korea jsleesnu@snu.ac.kr.
authors.forename: Joong Seok
authors.initials: JS
authors.lastname: Lee
authors.affiliation: Department of Mechanical and Aerospace Engineering, Institute of Advanced Machines and Design, Seoul National University, 1 Gwanak-ro, Gwanak-gu, 151-744 Seoul, Republic of Korea sungmin.wk@gmail.com, ykahn@snu.ac.kr, yykim@snu.ac.kr.
authors.forename: Sungmin
authors.initials: S
authors.lastname: Yoo
authors.affiliation: Department of Mechanical and Aerospace Engineering, Institute of Advanced Machines and Design, Seoul National University, 1 Gwanak-ro, Gwanak-gu, 151-744 Seoul, Republic of Korea sungmin.wk@gmail.com, ykahn@snu.ac.kr, yykim@snu.ac.kr.
authors.forename: Young Kwan
authors.initials: YK
authors.lastname: Ahn
authors.affiliation: Department of Mechanical and Aerospace Engineering, Institute of Advanced Machines and Design, Seoul National University, 1 Gwanak-ro, Gwanak-gu, 151-744 Seoul, Republic of Korea sungmin.wk@gmail.com, ykahn@snu.ac.kr, yykim@snu.ac.kr.
authors.forename: Yoon Young
authors.initials: YY
authors.lastname: Kim