A note on binary template matching

External shock loading on a submerged fluid-filled cylindrical shell

Interaction between a submerged evacuated cylindrical shell and a shock wave—Part I: Diffraction–radiation analysis

Interaction between an external shock wave and a cylindrical shell filled with and submerged into different fluids

In this study a theoretical framework for calculating the acoustic response of optical fiber-based ultrasound sensors is presented. The acoustic response is evaluated for optical fibers with several layers of coating assuming a harmonic point source with arbitrary position and frequency. First, the fiber is acoustically modeled by a layered cylinder on which spherical waves are impinged. The scattering of the acoustic waves is calculated analytically and used to find the normal components of the strains on the fiber axis. Then, a strain-optic model is used to calculate the phase shift experienced by the guided mode in the fiber owing to the induced strains. The framework is showcased for a silica fiber with two layers of coating for frequencies in the megahertz regime, commonly used in medical imaging applications. The theoretical results are compared to experimental data obtained with a sensing element based on a pi-phase-shifted fiber Bragg grating and with photoacoustically generated ultrasonic signals.

Characterization of the spatio-temporal response of optical fiber sensors to incident spherical waves

The transient scattering of spherical pressure pulses by an infinitely long acoustically hard circular cylinder is analyzed. The pressure in the neighborhood of the reflected wavefront is calculated by the method of series expansion in conjunction with the transport equations. From the wave equation, a simple integral formula is derived by means of which the solution to the present three‐dimensional problem can be effectively constructed from the two‐dimensional line source solution. Thus, the pressure in the neighborhood of the diffracted wavefront is computed based upon Friedlander’s diffraction formulas pertaining to the scatttering of a cylindrical pulse by a hard cylinder. Outside the neighborhood of the scattered wavefronts, the solution is obtained by the Fourier series and integral transform techniques and is accurately computed by this formula. By combining the various solutions, the true time histories of the scattered pressure are inferred for various locations on the cylinder. Some features of...

H. Huang

Papers

Scattering of spherical pressure pulses by a hard cylinder