scholarly journals On acoustic wave beaming in two-dimensional structural lattices

2017 ◽  
Vol 115-116 ◽  
pp. 248-269 ◽  
Author(s):  
Alex J. Zelhofer ◽  
Dennis M. Kochmann
Keyword(s):  
Acoustic Wave ◽  
Two Dimensional

Acoustic wave propagation in two dimensional sheared ducted flows

1997 ◽  
Author(s):  
E. Longatte ◽  
P. Lafon ◽  
S. Candel ◽  
E. Longatte ◽  
P. Lafon ◽  
...  
Keyword(s):  
Wave Propagation ◽  
Acoustic Wave ◽  
Two Dimensional ◽  
Acoustic Wave Propagation

Acoustic receptivity and evolution of two-dimensional and oblique disturbances in a Blasius boundary layer

2001 ◽  
Vol 432 ◽  
pp. 69-90 ◽  
Author(s):  
RUDOLPH A. KING ◽  
KENNETH S. BREUER
Keyword(s):  
Boundary Layer ◽  
Surface Roughness ◽  
Acoustic Wave ◽  
Three Dimensional ◽  
Two Dimensional ◽  
Surface Waviness ◽  
S Wave ◽  
Boundary Layer Instability ◽  
Blasius Boundary Layer ◽  
Tollmien Schlichting

An experimental investigation was conducted to examine acoustic receptivity and subsequent boundary-layer instability evolution for a Blasius boundary layer formed on a flat plate in the presence of two-dimensional and oblique (three-dimensional) surface waviness. The effect of the non-localized surface roughness geometry and acoustic wave amplitude on the receptivity process was explored. The surface roughness had a well-defined wavenumber spectrum with fundamental wavenumber kw. A planar downstream-travelling acoustic wave was created to temporally excite the flow near the resonance frequency of an unstable eigenmode corresponding to kts = kw. The range of acoustic forcing levels, ε, and roughness heights, Δh, examined resulted in a linear dependence of receptivity coefficients; however, the larger values of the forcing combination εΔh resulted in subsequent nonlinear development of the Tollmien–Schlichting (T–S) wave. This study provides the first experimental evidence of a marked increase in the receptivity coefficient with increasing obliqueness of the surface waviness in excellent agreement with theory. Detuning of the two-dimensional and oblique disturbances was investigated by varying the streamwise wall-roughness wavenumber αw and measuring the T–S response. For the configuration where laminar-to-turbulent breakdown occurred, the breakdown process was found to be dominated by energy at the fundamental and harmonic frequencies, indicative of K-type breakdown.

Highly directional acoustic wave radiation based on asymmetrical two-dimensional phononic crystal resonant cavity

2006 ◽  
Vol 88 (26) ◽  
pp. 263505 ◽  
Author(s):  
Manzhu Ke ◽  
Zhengyou Liu ◽  
Pei Pang ◽  
Wengang Wang ◽  
Zhigang Cheng ◽  
...  
Keyword(s):  
Acoustic Wave ◽  
Phononic Crystal ◽  
Resonant Cavity ◽  
Wave Radiation ◽  
Two Dimensional

Locally resonant surface acoustic wave band gaps in a two-dimensional phononic crystal of pillars on a surface

2010 ◽  
Vol 81 (21) ◽  
Author(s):  
Abdelkrim Khelif ◽  
Younes Achaoui ◽  
Sarah Benchabane ◽  
Vincent Laude ◽  
Boujamaa Aoubiza
Keyword(s):  
Acoustic Wave ◽  
Surface Acoustic Wave ◽  
Phononic Crystal ◽  
Band Gaps ◽  
Wave Band ◽  
Two Dimensional
Sign in / Sign up

Export Citation Format

Share Document