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A Review of Acoustic Impedance Matching Techniques for Piezoelectric Sensors and Transducers [PDF]
Sensors, 2020 The coupling of waves between the piezoelectric generators, detectors, and propagating media is challenging due to mismatch in the acoustic properties. The mismatch leads to the reverberation of waves within the transducer, heating, low signal-to-noise ...
Vivek T. Rathod
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Modelling Turbine Acoustic Impedance [PDF]
International Journal of Turbomachinery, Propulsion and Power, 2021 We quantify the sensitivity of turbine acoustic impedance to aerodynamic design parameters. Impedance boundary conditions are an influential yet uncertain parameter in predicting the thermoacoustic stability of gas turbine combustors.
James Brind, Graham Pullan
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Acoustic impedance of a cylindrical orifice [PDF]
Journal of Fluid Mechanics, 2020 Rodolfo Brandão, Ory Schnitzer
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Acoustic impedance-based surface acoustic wave chip for gas leak detection and respiratory monitoring [PDF]
Communications EngineeringAcoustic impedance enables many interesting acoustic applications. However, acoustic impedance for gas sensing is rare and difficult. Here we introduce a micro-nano surface acoustic wave (SAW) chip based on the acoustic impedance effect to achieve ultra ...
Baile Cui +7 more
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Method of Measuring the Acoustical Impedance [PDF]
The Journal of the Acoustical Society of America, 1969 An electrostatic transducer, made as a sandwich with a thin foil membrane, gives an output voltage, the first derivative of which is exactly proportional to the volume velocity passing through it. Such a sandwich is located at a place where the acoustic impedance is to be measured with a feeding loudspeaker in front of it.
Josef Merhaut
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Acoustical Impedance of Thin Diaphragms
The Journal of the Acoustical Society of America, 1967 Differential equation describing the deflection η of a thin circular diaphragm, loaded with a complex specific acoustical impedance per unit area is solved. Then the total acoustical impedance Za of the diaphragm defined by 1/Za = jω∫∫ηdS/p is calculated, where p is the acoustic pressure, and dS element of area.
Josef Merhaut
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Acoustic Impedance Measurements in Diagnosis [PDF]
Proceedings of the Royal Society of Medicine, 1974 Denzil N. Brooks
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The influence of impedance mismatch of the medium with gradient change of impedance on acoustic characteristics [PDF]
MATEC Web of Conferences, 2019 Medium with gradient change of acoustic impedance is a new type acoustic structure. It is composed of several materials and has a continuous gradient composition and structure whose specific acoustic impedance varies smoothly across the layer.
Hu Bo, Wang Moran, Du Yimei
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Acoustic impedance of orifices with grazing flow [PDF]
MATEC Web of Conferences, 2020 The paper presents an overview of the results of studies of acoustic impedance of orifices with grazing airflow. Empirical models of orifice impedance, which take into account the grazing flow, and the existing methods of measuring the acoustic impedance
Bejsenbaeva Diana +3 more
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Acoustics, 2020 Scanning acoustic microscopy reveals information on histology and acoustic impedance through tissues. The objective of the present study was to investigate whether acoustic impedance values in the liver over time reflect the progression of ...
Hideki Kumagai +5 more
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