scholarly journals Experimental Analysis of Ultrasonic Multiple Scattering Attenuation through the Air with Fine Dust

2021 ◽  
Vol 11 (2) ◽  
pp. 694
Author(s):  
Ukyong Woo ◽  
Hajin Choi ◽  
Homin Song
Keyword(s):  
Signal Processing ◽  
Multiple Scattering ◽  
Cross Section ◽  
Approximation Theory ◽  
Experimental Analysis ◽  
Scattering Theory ◽  
Ultrasonic Attenuation ◽  
Fine Dust ◽  
Ultrasonic Scattering ◽  
Scattering Attenuation

In this study, we experimentally evaluated the application of multiple scattering theory for measuring ultrasonic attenuation. Based on the independent approximation theory, the method adopted for calculating the attenuation of coherent waves through air with fine dust is discussed. To obtain a scattering wavefield, a unique ultrasonic scattering hardware was developed, and signal processing schemes were suggested. Four cases of standard particle doses (0, 0.004, 0.008, and 0.012 g) were investigated inside a chamber. The results obtained from the experiments demonstrate that the proposed signal processing approach successfully calculates the scattering attenuation, which correlates well with the applied doses of fine dust. In addition, we discuss the irregular shape and composition of fine dust relative to the scattering cross-section.

Multiple Scattering Calculations Applied to XAS: A Structure and Electronic Sensitive Tool

1991 ◽  
Vol 253 ◽  
Author(s):  
Philippe Sainctavit ◽  
J. Petiau
Keyword(s):  
Multiple Scattering ◽  
Cross Section ◽  
Absorption Cross Section ◽  
Scattering Theory ◽  
Spectral Features ◽  
Absorption Cross ◽  
Multiple Scattering Theory ◽  
X Ray ◽  
Sensitive Tool ◽  
X Ray Absorption

ABSTRACTWe present an application of multiple scattering theory with “muffin-tin” potentials to the calculation of X-ray absorption cross section. We have measured and calculated the K-edge spectra of atoms in compounds with zincblende structure : SiC, ZnS. We show that some spectral features can be precisely related to the local environnement around the absorbing atom.

ELASTIC pd SCATTERING AT HIGH ENERGIES

1988 ◽  
Vol 03 (05) ◽  
pp. 1301-1319 ◽  
Author(s):  
V.M. BRAUN ◽  
L.G. DAKHNO ◽  
V.A. NIKONOV
Keyword(s):  
Experimental Data ◽  
Differential Cross Section ◽  
Multiple Scattering ◽  
Cross Section ◽  
Differential Cross ◽  
Scattering Theory ◽  
High Energy ◽  
Multiple Scattering Theory ◽  
High Energies

High energy differential pd cross section is calculated in the framework of the multiple scattering theory, inelastic correction included. Special attention is paid to the analysis of the calculation uncertainties. The results agree well with the experimental data obtained at ISR energies in the q2 range 0.06–1.05 (GeV/c) 2. The calculation accuracy is proved to be not worse than 10–20% at q2~0.2 (GeV/c) 2 and much better at small q2, namely, ~1% in the optical point. Prediction for the differential cross section at UNK energy E lab =3 TeV is given.

scholarly journals Reflection of keV light ions from solids at oblique and grazing incidence

2009 ◽  
Vol 24 (3) ◽  
pp. 188-194 ◽  
Author(s):  
Jovan Vukanic ◽  
Rodoljub Simovic
Keyword(s):  
Reflection Coefficient ◽  
Multiple Scattering ◽  
Cross Section ◽  
Scattering Theory ◽  
Grazing Incidence ◽  
Universal Functions ◽  
Light Ions ◽  
Analytical Formulae ◽  
Analytical Approaches ◽  
Good Agreement

The particle reflection coefficient of light keV ions backscattered from heavy targets has been determined by two different analytical approaches: by the single collision model in the case of nearly perpendicular incidence and by the small-angle multiple scattering theory in the case of glancing angles of incidence. The obtained analytical formulae are approximately universal functions of the scaled transport cross-section describing the reflection of all light ions from heavy targets. Going from perpendicular to grazing incidence, the transition from pure single to pure multiple scattering type of reflection is observed. For larger values of the scaling parameter the results of these theories cover the whole region of ion incident angles and the present estimates of the particle reflection coefficient are in good agreement with the results obtained from the empirical formula of Tabata et al.

On the Influence of the Slot Orifice in Diesel Common Rail Nozzle

2018 ◽  
Vol 11 (1) ◽  
pp. 55-69 ◽  
Author(s):  
Giancarlo Chiatti ◽  
Ornella Chiavola ◽  
Fulvio Palmieri ◽  
Roberto Pompei
Keyword(s):  
Cross Section ◽  
Flow Rate ◽  
Experimental Analysis ◽  
Common Rail ◽  
Spray Angle ◽  
The Novel ◽  
Hydraulic Behavior ◽  
Reference Information ◽  
Light Duty ◽  
Set Up

Background:The paper deals with a diesel common rail nozzle in which a novel orifice layout is implemented.Objective:Its influence on the nozzle mechanical-hydraulic behavior and on the spray shape transient development is experimentally investigated.Methods:In the research, a solenoid injector for light duty diesel engines is equipped with the novel nozzle prototype and tested. The prototype layout is described, pointing out the features of the nozzle orifices, in which a Slot cross-section is adopted; the investigation is accomplished extending the hydraulic tests and the spray visualizations to a reference nozzle with standard holes. The influence of the hole layout on the mechanical-hydraulic behavior of the nozzle is assessed by experimental analysis based on the rate of injection measurement, in comparison with the reference nozzle. Once the hydraulic behavior of the novel nozzle has been characterized in terms of mass flow rate, the slot influence on the spray shape is assessed analyzing the macroscopic features such as the penetration distance and the spray angle, in non evaporative conditions. The study is carried out under transient injection conditions, for different injection pressures, up to 1400 bar.Results:The results on spray characteristics also provide reference information to set up spray models suited to take the Slot orifice into account.

scholarly journals Experimental demonstration of negative refraction with 3D locally resonant acoustic metafluids

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Benoit Tallon ◽  
Artem Kovalenko ◽  
Olivier Poncelet ◽  
Christophe Aristégui ◽  
Olivier Mondain-Monval ◽  
...  
Keyword(s):  
Experimental Data ◽  
Yield Stress ◽  
Multiple Scattering ◽  
Silicone Rubber ◽  
Acoustic Waves ◽  
Scattering Theory ◽  
Negative Refraction ◽  
Volume Fraction ◽  
Experimental Demonstration ◽  
Acoustic Beam

AbstractNegative refraction of acoustic waves is demonstrated through underwater experiments conducted at ultrasonic frequencies on a 3D locally resonant acoustic metafluid made of soft porous silicone-rubber micro-beads suspended in a yield-stress fluid. By measuring the refracted angle of the acoustic beam transmitted through this metafluid shaped as a prism, we determine the acoustic index to water according to Snell’s law. These experimental data are then compared with an excellent agreement to calculations performed in the framework of Multiple Scattering Theory showing that the emergence of negative refraction depends on the volume fraction $$\Phi$$ Φ of the resonant micro-beads. For diluted metafluid ($$\Phi =3\%$$ Φ = 3 % ), only positive refraction occurs whereas negative refraction is demonstrated over a broad frequency band with concentrated metafluid ($$\Phi =17\%$$ Φ = 17 % ).

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