Results 11 to 20 of about 32,369 (300)
Resistive-wall impedance of two-layer tube
Physical Review Special Topics. Accelerators and Beams, 2007 In contrast to electron machines, beam particles travel in most proton or heavy ion circular accelerators with nonrelativistic speed. The resistive-wall impedance of the cylindrical two-layer tube with finite thickness is studied in this paper for any ...
N. Wang, Q. Qin
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The Measurement of Low Frequency Impedance Using an Impedance Tube
Journal of Low Frequency Noise, Vibration and Active Control, 1998 An accurate and reliable prediction of car interior noise would be a significant step towards improving the design of car body panels and trim for a quieter vehicle. Automobile noise is dominated by low frequencies, from 50 to 300 Hz and therefore a technique is necessary to measure acoustic impedance of the trim materials at low frequencies.
C Peng, D Morrey, P Sanders
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Acoustic Pitfalls of Impedance Tube Measurements
, 2019 The impedance tube is commonly used to characterize sound absorbing material. In order to obtain reliable results, the sample must fit perfectly into the cross section of the tube. In practice, this often results in a minimal gap between the sample and the wall of the tube. A narrow gap causes thermoviscous damping.
Graf, Thomas
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Design and experimental evaluation of a travelling wave thermoacoustic engine
Energy Reports, 2020 In a thermoacoustic engine, acoustic impedance plays a key role to improve the system performance. A matching stub is a component which can be applied to adjust the acoustic impedance.
Patcharin Saechan, Isares Dhuchakallaya
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Acoustic characterisation of liquid foams with an impedance tube [PDF]
The European Physical Journal E, 2013 Acoustic measurements provide convenient non-invasive means for the characterisation of materials. We show here for the first time how a commercial impedance tube can be used to provide accurate measurements of the velocity and attenuation of acoustic waves in liquid foams, as well as their effective "acoustic" density, over the 0.5-6kHz frequency ...
Pierre, Juliette +4 more
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Multilayer Impedance Pump: A Bio-Inspired Valveless Pump with Medical Applications [PDF]
, 2007 This thesis introduces the concept of multilayer impedance pump, a novel pumping mechanism inspired from the embryonic heart structure. The multilayer impedance pump is a composite two-layer fluid-filled elastic tube featuring a thick, gelatin-like ...
Loumes, Laurence
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Determination of the interaction impedance of helix slow-wave structures. [PDF]
, 2000 The computer simulation of helix travelling-wave tubes requires accurate information about the phase velocity, interaction impedance and attenuation of the helix slow wave structure at each frequency.
R.G. Carter, Carter, R. G.
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Effects of intermediary reservoir in a two-stage impedance pump
MATEC Web of Conferences, 2017 Impedance pump is a simple valve-less pumping mechanism, which transport fluid through the mismatch of impedance in the system. A typical open-loop impedance pump consists of an elastic tube, connected to rigid tubing, where the rigid section is ...
Lee V. C.-C., Chong J.-C
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Panel of resonators with variable resonance frequency for noise control [PDF]
, 2012 The article focuses on acoustic resonators made of perforated sheets bonded onto honeycomb cavities. This kind of resonators can be used in adverse conditions such as high temperature, dirt and mechanical constraints. For all these reasons, they are, for
Pommier-Budinger, V. +7 more
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A comparison between hybrid method technique and transfer matrix method for design optimization of vehicle muffler [PDF]
FME Transactions, 2021 Hybrid mufflers are now commonly equipped to decrease vehicle noise and are a crucial tool for regulation of the acoustic system. In order to ensure optimum engine efficiency, the system is intended to dump the strength of the acoustic pulses generated ...
Mohamad Barhm +3 more
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