Passive models of viscothermal wave propagation in acoustic tubes

Wave propagation in elastic tubes

Viscothermal Wave Propagation including Acousto-elastic Interaction, Part Ii: Applications

In Part I of the present paper a parameter analysis showed that the most e$cient model to describe viscothermal wave propagation is the low reduced frequency model. In order to demonstrate the wide range of applicability of the low reduced frequency model, a number of examples from the literature are discussed in Part II. An overview of fundamental solutions and general applications is given. B...

Viscothermal Wave Propagation including Acousto-elastic Interaction, Part I: Theory

This research deals with pressure waves in a gas trapped in thin layers or narrow tubes. In these cases viscous and thermal e!ects can have a signi"cant e!ect on the propagation of waves. This so-called viscothermal wave propagation is governed by a number of dimensionless parameters. The two most important parameters are the shear wave number and the reduced frequency. These parameters were us...

Abnormal Wave Propagation in Passive Media

Abnormal velocities in passive structures such as one-dimensional (1-D) photonic crystals and a slab having a negative index of refraction are discussed. In the case of 1-D photonic crystal, the frequencyand time-domain experiments for waves tuned to the bandgap of the photonic crystal demonstrate a positive group velocity exceeding the speed of light in vacuum (superluminal). In the case of a ...

Parallel implementation of underwater acoustic wave propagation using beamtracing method on graphical processing unit

The mathematical modeling of the acoustic wave propagation in seawater is the basis for realizing goals such as, underwater communication, seabed mapping, advanced fishing, oil and gas exploration, marine meteorology, positioning and explore the unknown targets within the water. However, due to the existence of various physical phenomena in the water environment and the various conditions gover...