Ultrasonic cavity solitons

Abstract

We report on a new type of localized structure, an ultrasonic cavity soliton, supported by large aspect-ratio acoustic resonators containing viscous media. The spatio-temporal dynamics of this system is analyzed on the basis of a generalized Swift-Hohenberg equation, derived from the microscopic equations under conditions close to nascent bistability. These states of the acoustic and thermal fields are robust structures, existing whenever a spatially uniform solution and a periodic pattern coexist. An analytical solution for the ultrasonic cavity soliton is also presented. 75.80.+q, 43.25.+y

Microscale acoustofluidics: Microfluidics driven via acoustics and ultrasonics

“…But it is interesting that currently the focus remains on the propagation of such waves in solids alone. The contribution by Perez-Arjona et al (2008) in describing stable solitons trapped within a cavity structure containing a viscous media offered a hint of the possibilities in this field if one were to incorporate fluids.…”

Derivation of the spatio-temporal model equations for the thermoacoustic resonator

“…This model exhibits a rich spatiotemporal dynamics and exhibits pattern formation and localized structure formed in the transverse cross-section of the cavity. Some of these results are studied in [5].…”

Pattern Formation And Localized Structures In Acoustic Resonators Containing A Viscous Fluid

“…Where P~p, H~ T h and G~ T g (for details, see [5]) and the normalized variables W=t/t h is time measured in units of the relaxation time of homogeneous temperature t h and W p =t p /t h and W g =t g /t h are, respectively, the normalized relaxation times of the intracavity pressure and the grating component of the temperature. The other parameters are the detuning '=(ZZ c ) where Z c corresponds to the cavity frequency nearest to the driving frequency w, and P in~pin , with p in the injected pressure plane wave amplitude.…”

“…Close to the NB point, the model (1) can be reduced to a single order parameter equation through a multiple scales analysis [5]. Following standard procedures a closed equation for the variable h is obtained…”