Non-localized impulsive sources are ubiquitous in underwater acoustic applications. However, analytical expressions of their acoustic field are usually not available. In this work, far-field analytical solutions of the non-homogeneous scalar Helmholtz and wave equations are developed for a class of spatially extended impulsive sources. The derived expressions can serve as benchmarks to verify the accuracy of numerical solvers.

Download full-text PDF

Source
http://dx.doi.org/10.1121/10.0017067DOI Listing

Publication Analysis

Top Keywords

far-field analytical
8
analytical solutions
8
solutions non-homogeneous
8
helmholtz wave
8
wave equations
8
impulsive sources
8
non-homogeneous helmholtz
4
equations spatially
4
spatially non-localized
4
non-localized sources
4

Similar Publications

Analytical solutions for acoustic vortex beams radiated by sources with uniform circular amplitude distributions are derived in the paraxial approximation. Evaluation of the Fresnel diffraction integral in the far field of an unfocused source and in the focal plane of a focused source leads to solutions in terms of an infinite series of Bessel functions for orbital numbers ℓ>-2. These solutions are reduced to closed forms for 0≤ℓ≤4, which correspond to orbital numbers commonly used in experiments.

View Article and Find Full Text PDF

Moiré metasurfaces exhibit high optical tuneabilities and versatile light manipulation capabilities. Both infinite quality factor (Q factor) and topological vortex configurations in momentum space (-space) of the bound state in the continuum (BIC) have introduced new dimensions for light modulation. Herein, we propose a moiré metasurface comprising two identical square photonic lattices superimposed with a commensurate angle of 12.

View Article and Find Full Text PDF

Effectiveness of multi-junction cells in near-field thermophotovoltaic devices considering additional losses.

Nanophotonics

March 2024

Department of Mechanical Engineering, KAIST, 291, Daehak-ro, Yuseong-gu, Daejeon-si 34141, South Korea.

Article Synopsis
  • Thermophotovoltaic (TPV) energy converters can efficiently transform thermal radiation into electrical energy, with diverse applications including solar energy collection and waste heat recovery.
  • Near-field TPV (NF-TPV) devices use photon tunneling to enhance power output density but face challenges from losses related to high photocurrent densities and scalability issues.
  • This study evaluates multi-junction NF-TPV devices, introduces methods to assess additional loss impacts, and offers a framework for improving performance across various parameters, ultimately guiding the design of scalable and high-performing TPV systems.
View Article and Find Full Text PDF
Article Synopsis
  • Photo-induced force microscopy (PiFM) is a high-resolution imaging technique that utilizes photo-induced forces to enhance tip movement, allowing for detailed nanoscale spectroscopic imaging.
  • This review covers the complexities of PiFM, including the influences of both local dipole interactions and thermal expansion, and distinguishes between far-field and near-field effects.
  • The article serves as a comprehensive guide for beginners, combining theoretical insights with practical examples that span from basic concepts to more advanced topics in the field.
View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!