... of 10, 20, and 50 mm. The ultrasound transducers were 1 MHz lead zirconate titanate discs, and a signal generator was used to drive them. Voltages across the transmission transducer and “implanted” transducer were recorded with and without water and with acoustic gel used as coupling agents between...

... arising from pressure wave exposure, such as blast wave injuries. However, the subfield of acoustic wave exposure is distinct from auditory damage arising in loud workplace environments, where noise exposure, following conventional, well characterized pathways, is related to hearing loss...

..., vortex shedding, compressible flow, acoustics, cavity transition, juts, turbulence, computational aeroacoustics, cavity flow, shear layer, cavity flow control, passive flow control FIGURE 1: FLOW CONTROL JUTS VISUALIZATION NOMENCLATURE Depth of the cavity Length of the cavity Mach number Freestream...

... component will propagate within the downstream pipe. This internal acoustic field will couple to the pipe wall and cause it to vibrate, which in turn causes external radiation. The difference between the internal and external sound fields is called transmission loss. The estimation of the transmission loss...

... , B. W. Anthony1 1Massachusetts Institute of Technology, Cambridge, MA ABSTRACT Acoustophoretic assembly uses a standing acoustic eld to move dispersed small particles into a geometric pattern. The technique relies on the acoustic radiation force, which arises from the interaction between...

..., Taikang Ning1 1Trinity College, Hartford, CT ABSTRACT The influence of surface roughness on the acoustic spectrum in a pulsing restricted flow is investigated over a range of roughness sizes and flow conditions. Four different roughness scenarios are introduced, ranging from smooth to a relative roughness...

... Abstract A parametric study of the influence of flow restriction and Reynolds number on the acoustic spectrum is performed. By altering the boundary conditions of the pulsatile flow, changes in frequency coupling can be investigated. To mimic aortic valve stenosis in a resting heart...

... Turning flow into side branches against a deadleg along the main run can generate high levels of pulsations if the piping system acoustic resonance frequency matches closely the flow generated instabilities within the T-junction characterized by specific Strouhal number (St) that is function of the branch...

.... Strouhal number characterized the flow-acoustic field for the three d/D ratios and for acoustically tuned and detuned systems. It was found that P* decreases as d/D decreases for acoustically tuned systems. The highest P* was achieved with d/D = 1 which reached a value of 3.543 at St = 0.1376. At lower d/D...

... Abstract Triply Poly Minimal Surfaces (TPMS) are three dimensional periodic lattice structures with a trigonometric relationship in their unit cell that can be implemented for acoustic applications including acoustic metamaterials and Phononic crystals. The necessity and demand...

...ACOUSTIC AMPLIFICATION OF FLOW RIPPLE AND CAVITATION DAMAGE IN AN AEROSPACE FUEL SYSTEM COMPONENT Andrew Lee 1 , Mihir Desai 1 1 Rolls-Royce Corporation, Indianapolis, IN, USA ABSTRACT In a recent investigation of external fuel leaks from an aerospace pressure control valve, cavitation damages were...

... as they are renewable, sustainable, and reduce engine emissions. However, nitric oxides (NO) and nitrogen dioxides (NO 2 ) are typically released in greater proportion, generally known as NOx. Applying acoustic excitation on a biofuel operated engine exhaust gases is investigated with and without reburn. Four biofuels...

... Identification and localization of leaks in water pipelines using acoustic methods have been utilized for many years. Most of the existing acoustic leak detection techniques rely on external measurements of sound emitted from the turbulent jet of water escaping the pipe. Direct acoustic...

... 01 05 2012 Resonance inspection uses the natural acoustic resonances of a part to identify anomalous parts. Modern instrumentation can measure the many resonant frequencies rapidly and accurately. Sophisticated sorting algorithms trained on sets of good and anomalous parts can rapidly...

... NDE acoustics nonlinear frequency spectrum retrofit FRP concrete damage Many recent studies have indicated that externally bonded Fiber Reinforced Plastic (FRP) composite sheets can be used effectively to strengthen concrete structures. Composite action suggests that the individual...

... 18 01 2008 We address acoustic transmission loss through doubly-periodic elastic panels separating two semi-infinite fluid half-spaces. This involves the computation of the transmitted and reflected sound fields due to an incident plane wave. The elastic panel may have complex internal...