相关论文: Acoustic radiation force and streaming induced by …

New theoretical formulae of the sound velocity and the B/A nonlinearity parameter for some fluids are presented in the paper. Semi--ideal and van der Waals models of gas are considered and the parameters are compared to experiment data. The…

We study the dynamical behaviors of a system of five coupled nonlinear equations that describes the dynamics of acoustic-gravity waves in the atmosphere. A linear stability analysis together with the analysis of Lyapunov exponents spectra…

We provide a detailed analysis on the acoustic radiation force and torque exerted on a homogeneous viscoelastic particle in the long-wave limit (the particle radius is much smaller than the incident wavelength) by an arbitrary wave. We…

The bubbles involved in sonochemistry and other applications of cavitation oscillate inertially. A correct estimation of the wave attenuation in such bubbly media requires a realistic estimation of the power dissipated by the oscillation of…

For energy efficiency and material cost reduction it is preferred to drive high-intensity discharge lamps at frequencies of approximately 300 kHz. However, operating lamps at these high frequencies bears the risk of stimulating acoustic…

We investigate diffusion in supersonic, turbulent, compressible flows. Supersonic turbulence can be characterized as network of interacting shocks. We consider flows with different rms Mach numbers and where energy necessary to maintain…

The classical problem of steady streaming induced by an oscillating object has been studied extensively, but prior work has focused almost exclusively on single-frequency oscillations, which result in symmetric, quadrupole-like flows. Here…

Energy flux is an acoustic propagation model that calculates the locally-averaged intensity without computing explicit eigenvalues or tracing rays. The energy flux method has so far only been used for two-dimensional problems that have…

We consider the sound radiation from an acoustic point-like source moving along a supersonic ("space-like") trajectory in a fluid at rest. We call it an acoustic "tachyonic" source. We describe the radiation emitted by this supersonic…

The propagation of acoustic-gravity waves (AGWs) in the stratified isothermal atmosphere is analyzed using methods of the oscillation theory. It is shown that AGW in the atmosphere can be considered as an oscillatory process occurring at…

We present a semi-analytical theory for the acoustic fields and particle-trapping forces in a viscous fluid inside a capillary tube with arbitrary cross section and ultrasound actuation at the walls. We find that the acoustic fields vary…

Transition radiation from relativistic electrons is investigated in an ultrasonic superlattice excited in a finite thickness plate. In the quasi-classical approximation formulae are derived for the vector potential of the electromagnetic…

Atmospheres having a significant radiative support are shown to be intrinsically unstable at luminosities above a critical fraction Gamma_crit ~ 0.5-0.85 of the Eddington limit, with the exact value depending on the boundary conditions. Two…

We investigate the formation of acoustic horizons for an inviscid fluid moving in a pipe in the case of stationary and axi-symmetric flow. We show that, differently from what is generally believed, the acoustic horizon forms in…

Driven systems are of fundamental scientific interest, as they can exhibit properties that are radically different from the same system at equilibrium. In certain cases, long-lived states of driven matter can emerge, which exhibit new…

We derive system of equations describing fluidity of the medium consisting of non-relativistic particles with finite mass-widths. For that we use expressions for the kinetic Noether 4-current and the Noether energy-momentum tensor being…

We consider a harmonically driven acoustic medium in the form of a (finite length) highly nonlinear granular crystal with an amplitude and frequency dependent boundary drive. Remarkably, despite the absence of a linear spectrum in the…

Most measurement methods based on ultrasound, such as sound velocity, absorption or flow measurement systems, require that the acoustic wave propagation is linear. In many cases, linear wave propagation is assumed due to small signal…

Exact formulas of the acoustic radiation force and torque exerted by an arbitrary time-harmonic wave on an absorbing compressible particle that is suspended in an inviscid fluid are presented. It is considered that the particle diameter is…

Acoustic radiation due to vibration and impact of a spring-mass-damper oscillator whose motion is constrained by a barrier is analyzed at a field point in a free field. Impact between the mass and the barrier is modeled using a coefficient…