Related Experiment Video
Updated: Dec 31, 2025
09:37
Visualization of Flow Field Around a Vibrating Pipeline Within an Equilibrium Scour Hole
Published on: August 26, 2019
6.0K
Generation of vortex waves in non-coaxial cylindrical waveguides
Artem S Pilipchuk1, Alina A Pilipchuk1, Almas F Sadreev1
1Kirensky Institute of Physics, Federal Research Center KSC SB RAS, 660036 Krasnoyarsk, Russia.
The Journal of the Acoustical Society of America
|January 3, 2020
Summary
This study demonstrates efficient conversion of acoustic waves with zero orbital angular momentum (OAM) to non-zero OAM states using a non-coaxial waveguide. Optimal configurations achieve nearly 100% conversion efficiency.
Area of Science:
- Acoustics
- Waveguide theory
- Orbital Angular Momentum (OAM)
Background:
- Non-coaxial waveguide structures can manipulate wave properties.
- Orbital Angular Momentum (OAM) offers new possibilities for wave control.
Purpose of the Study:
- To investigate the conversion of acoustic waves from zero OAM to non-zero OAM states.
- To analyze the efficiency of this conversion in a non-coaxial waveguide system.
Main Methods:
- Utilized a non-coaxial waveguide with a cylindrical resonator and offset input/output waveguides.
- Investigated the effect of waveguide geometry (radii r1, r2, R) and relative center line shift (Δϕ).
- Analyzed conversion efficiency as a function of frequency and resonator length.
Main Results:
- Achieved efficient conversion from zero OAM to non-zero OAM acoustic wave channels.
- Identified specific operating domains yielding nearly 100% conversion efficiency.
- Demonstrated that efficiency depends on frequency, resonator length, and the angular shift Δϕ.
Conclusions:
- Non-coaxial waveguide design enables effective OAM conversion for acoustic waves.
- The study provides insights into optimizing waveguide parameters for high-efficiency OAM manipulation.
- This work has potential applications in acoustic signal processing and communication.
Related Concept Videos
01:28Standing Waves in a Cavity
1.4K
A household microwave and lasers are examples of standing electromagnetic waves in a cavity. When two conducting metal plates are placed parallel at the nodal planes, it creates a cavity where standing waves are formed. The cavity between the two planes is analogous to a stretched string held at the points x = 0 and x = L. Here, the distance 'L' between the two planes must be an integer multiple of half of the wavelength. The wavelengths that satisfy this condition are given by:
1.4K
01:30Plane Electromagnetic Waves I
4.8K
The existence of combined electric and magnetic fields that propagate through space as electromagnetic (EM) waves is the most significant prediction of Maxwell's equations. As Maxwell's equations hold in free space, the predicted electromagnetic waves do not require a medium for their propagation. An EM wave comprises an electric field, defined as the force per charge on a stationary charge, and a magnetic field, which is the force per charge on a moving charge.
The EM field is assumed to be a...
The EM field is assumed to be a...
4.8K
01:15Standing Electromagnetic Waves
2.1K
Electromagnetic waves can be reflected; the surface of a conductor or a dielectric can act as a reflector. As electric and magnetic fields obey the superposition principle, so do electromagnetic waves. The superposition of an incident wave and a reflected electromagnetic wave produces a standing wave analogous to the standing waves created on a stretched string.
Suppose a sheet of a perfect conductor is placed in the yz-plane, and a linearly polarized electromagnetic wave traveling in the...
Suppose a sheet of a perfect conductor is placed in the yz-plane, and a linearly polarized electromagnetic wave traveling in the...
2.1K
01:10Generating Electromagnetic Radiations
6.5K
The German physicist Heinrich Hertz (1857–1894) was the first to generate and detect certain types of electromagnetic waves in the laboratory. Starting in 1887, he performed a series of experiments that confirmed the existence of electromagnetic waves and verified that they travel at the speed of light. Hertz used an alternating-current RLC (resistor-inductor-capacitor) circuit that resonated at a known frequency and connected it to a loop of wire. High voltages induced across the gap in...
6.5K
01:24Electromagnetic Wave Equation
2.0K
Maxwell's equations for electromagnetic fields are related to source charges, either static or moving. These fields act on a test charge, whose trajectory can thus be determined using suitable boundary conditions. The objective of electromagnetism is thus theoretically complete.
However, although electric and magnetic fields were first introduced as mathematical constructs to simplify the description of mutual forces between charges, a natural question emerges from Maxwell's equations:...
However, although electric and magnetic fields were first introduced as mathematical constructs to simplify the description of mutual forces between charges, a natural question emerges from Maxwell's equations:...
2.0K
01:20Gauss's Law: Cylindrical Symmetry
9.2K
A charge distribution has cylindrical symmetry if the charge density depends only upon the distance from the axis of the cylinder and does not vary along the axis or with the direction about the axis. In other words, if a system varies if it is rotated around the axis or shifted along the axis, it does not have cylindrical symmetry. In real systems, we do not have infinite cylinders; however, if the cylindrical object is considerably longer than the radius from it that we are interested in,...
9.2K