Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Deriving the Speed of Sound in a Liquid01:09

Deriving the Speed of Sound in a Liquid

905
As with waves on a string, the speed of sound or a mechanical wave in a fluid depends on the fluid's elastic modulus and inertia. The two relevant physical quantities are the bulk modulus and the density of the material. Indeed, it turns out that the relationship between speed and the bulk modulus and density in fluids is the same as that between the speed and the Young's modulus and density in solids.
The speed of sound in fluids can be derived by considering a mechanical wave...
905
Pressure Variation in a Fluid at Rest01:11

Pressure Variation in a Fluid at Rest

734
In a fluid at rest, the pressure at any point beneath the fluid surface depends solely on the depth, not on the container's shape or size. This principle, known as hydrostatic pressure, arises because, in stationary fluids, there is no acceleration, meaning the forces within the fluid balance out. Only vertical forces, caused by the weight of the fluid above, contribute to pressure changes with depth.
When measuring pressure at two different levels within the fluid, the difference in...
734
Fluid Pressure over Curved Plate of Constant Width01:12

Fluid Pressure over Curved Plate of Constant Width

1.9K
When a curved plate of constant width is submerged in a liquid, the pressure acting normal to the plate varies continuously both in magnitude and direction. Calculating the magnitude and location of the resultant force at a point is often challenging for such cases. One of the methods to determine the resultant force and its location involves separately calculating the horizontal and vertical components of the resultant force. This complex calculation can be simplified by representing the...
1.9K
Viscosity of Fluid01:19

Viscosity of Fluid

1.2K
Viscosity measures the resistance a fluid offers to flow and deformation. It results from internal friction between layers of fluid moving relative to one another. Dynamic viscosity, denoted by the Greek letter mu (μ), quantifies the force needed to move one fluid layer over another. For Newtonian fluids like water and air, the relationship between the shearing stress and the rate of shearing strain is linear, meaning their viscosity remains constant regardless of the applied stress.
1.2K
Accelerating Fluids01:17

Accelerating Fluids

2.1K
When a fluid is in constant acceleration, the pressure and buoyant force equations are modified. Suppose a beaker is placed in an elevator accelerating upward with a constant acceleration, a. In the beaker, assume there is a thin cylinder of height h with an infinitesimal cross-sectional area, ΔS.
The motion of the liquid within this infinitesimal cylinder is considered to obtain the pressure difference. Three vertical forces act on this liquid:
2.1K
Navier–Stokes Equations01:28

Navier–Stokes Equations

2.1K
For incompressible Newtonian fluids, where density remains constant, stresses show a linear relationship with the deformation rate, defined by normal and shear stresses. Normal stresses depend on the pressure exerted on the fluid and the rate of deformation in specific directions, which determines how fluid flows under varying pressures. Shear stresses, on the other hand, act tangentially across fluid layers. They explain how adjacent fluid layers slide relative to one another, connecting...
2.1K

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same journal

Genetic algorithm-informed microjet control for noise reduction in supersonic impinging jetsa).

The Journal of the Acoustical Society of America·2026
Same journal

Physics-regularized neural acoustic fields for spatial layout inference from sparse room impulse responsesa).

The Journal of the Acoustical Society of America·2026
Same journal

Impedance eduction method based on multiple measurements with different incident modes in cylindrical ducts with reflective terminations.

The Journal of the Acoustical Society of America·2026
Same journal

Review of ultrasonic methods for monitoring, damage detection, and processing of lithium-ion batteries throughout their life cycle.

The Journal of the Acoustical Society of America·2026
Same journal

Assessment of silver nanoparticle mediated changes in osmotic fragility of red blood cells by a LASER diode based photoacoustic system.

The Journal of the Acoustical Society of America·2026
Same journal

Topographic effects on reflected acoustic waves from the OSIRIS-REx reentry observed from stratospheric balloons.

The Journal of the Acoustical Society of America·2026

Related Experiment Video

Updated: Jan 16, 2026

Fabrication, Operation and Flow Visualization in Surface-acoustic-wave-driven Acoustic-counterflow Microfluidics
12:26

Fabrication, Operation and Flow Visualization in Surface-acoustic-wave-driven Acoustic-counterflow Microfluidics

Published on: August 27, 2013

17.7K

Space-time dependent fluid acoustics and the generation of vorticity.

John D Smith1

  • 1Defence Science and Technology Laboratory, Porton Down, Salisbury, SP4 0JQ, United Kingdom.

The Journal of the Acoustical Society of America
|September 26, 2025
PubMed
Summary

This study examines wave propagation in fluids with changing properties. It finds that vorticity is generated at the wavefront, appearing to travel at sound speed, not with the fluid flow.

More Related Videos

Visualization of Flow Field Around a Vibrating Pipeline Within an Equilibrium Scour Hole
09:37

Visualization of Flow Field Around a Vibrating Pipeline Within an Equilibrium Scour Hole

Published on: August 26, 2019

6.1K
Induction of Microstreaming by Nonspherical Bubble Oscillations in an Acoustic Levitation System
08:19

Induction of Microstreaming by Nonspherical Bubble Oscillations in an Acoustic Levitation System

Published on: May 9, 2021

2.7K

Related Experiment Videos

Last Updated: Jan 16, 2026

Fabrication, Operation and Flow Visualization in Surface-acoustic-wave-driven Acoustic-counterflow Microfluidics
12:26

Fabrication, Operation and Flow Visualization in Surface-acoustic-wave-driven Acoustic-counterflow Microfluidics

Published on: August 27, 2013

17.7K
Visualization of Flow Field Around a Vibrating Pipeline Within an Equilibrium Scour Hole
09:37

Visualization of Flow Field Around a Vibrating Pipeline Within an Equilibrium Scour Hole

Published on: August 26, 2019

6.1K
Induction of Microstreaming by Nonspherical Bubble Oscillations in an Acoustic Levitation System
08:19

Induction of Microstreaming by Nonspherical Bubble Oscillations in an Acoustic Levitation System

Published on: May 9, 2021

2.7K

Area of Science:

  • Acoustics and Fluid Dynamics
  • Wave Propagation in Complex Media

Background:

  • Investigates wave propagation in fluids with spatially and temporally varying material properties.
  • Considers scenarios where viscosity and underlying fluid flow due to space-time variations are negligible.
  • Derives self-adjoint wave equations, diverging from conventional pressure acoustics.

Purpose of the Study:

  • To analyze wave motion in fluids with non-uniform properties, specifically addressing the generation of vorticity.
  • To explore the behavior of wave propagation when material properties vary spatially.
  • To examine the impact of nonlinearities on wave characteristics.

Main Methods:

  • Derivation of self-adjoint wave equations for fluids with varying properties.
  • Analysis of an ideal fluid with sound speed variations caused by temperature changes at a fixed wall.
  • Approximate solutions for wave propagation under specific conditions.
  • Brief examination of nonlinear effects on wave characteristics.

Main Results:

  • Wave motion in spatially varying media is not purely dilatational and exhibits associated vorticity.
  • Vorticity is generated at the wavefront, propagating at sound speed, distinct from underlying fluid flow.
  • Nonlinearities in sound scattering from sound on a constant background fluid induce solenoidal components in mass flux density but do not generate vorticity.

Conclusions:

  • Spatial variations in fluid properties fundamentally alter wave dynamics, leading to vorticity generation at the wavefront.
  • The apparent propagation of vorticity at sound speed is a key characteristic in these non-uniform media.
  • Nonlinear effects, while influencing mass flux, do not contribute to vorticity generation in the examined scenario.