Dislodgement and removal of dust‐particles from a surface relevant to NASA project by vibration and acoustic levitation.

Junru Wu; Di Chen

doi:10.1121/1.3588176

Design and Test of a Multi-Axis Acoustic-Levitation Device for Non-Contact Dust Removal from Precision Instruments

Research in Education Assessment and Learning ◽

10.37906/real.2020.3 ◽

2020 ◽

Vol 5 (1) ◽

Author(s):

Yudi Niu ◽

Yifan Pu ◽

Xiaoqi Che ◽

Mei Wang

Keyword(s):

Dust Removal ◽

Dust Particles ◽

Acoustic Levitation ◽

Particle Properties ◽

Modeling Simulation ◽

Voltage Output ◽

Demonstration Experiment ◽

Industrial Solution ◽

Light Absorbance ◽

Industrial Problem

To resolve the issues of the conventional dust removing method, such as electrostatic suspension and direct wiping with special lens paper, which can cause damage to precision instruments and their dependence on specific dust particle properties, we present a novel acoustic-levitation device design which incorporates an initial design of a multi-axis levitation device by Marzo. A. with our enhancement model based on the variation of transducers numbers and their spacing to achieve the dust removing efficiency and feasibility in real dust removal process. In this work, modeling simulation in COMSOL Multiphysics and light absorbance experiment are performed to evaluate the distribution of acoustic fields, trajectory of dust particles, and dust removing efficiency. With the manufactured device based on our design, the varying factors are characterized that may influence the removing efficiency when output voltage generated onto motor driven board is altered. Experiment shows 27.5 V is the most efficient voltage output with highest dust removal proportion in actual removing operations. The study demonstrates our design can achieve higher dust removing efficiency comparing to conventional methods. Whereas our design serves the purpose to solve a practical industrial problem, this paper also shows how it can be taken into the classroom as an demonstration experiment, providing an animated way to visualize the nodes and antinodes by the levitation position of particles, which help the students to not only understand the physical properties of standing waves, but also the connection from a classroom lab to an industrial solution.

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Saturn's E, G and F rings: modulated by the plasma sheet

International Astronomical Union Colloquium ◽

10.1017/s0252921100101666 ◽

1984 ◽

Vol 75 ◽

pp. 597

Author(s):

E. Grün ◽

G.E. Morfill ◽

T.V. Johnson ◽

G.H. Schwehm

Keyword(s):

Solar Wind ◽

Direct Contact ◽

Transport Processes ◽

Time Variable ◽

Dust Particles ◽

Spatial Diffusion ◽

Drag Forces ◽

Orbit Perturbation ◽

Time Variations ◽

F Ring

ABSTRACTSaturn's broad E ring, the narrow G ring and the structured and apparently time variable F ring(s), contain many micron and sub-micron sized particles, which make up the “visible” component. These rings (or ring systems) are in direct contact with magnetospheric plasma. Fluctuations in the plasma density and/or mean energy, due to magnetospheric and solar wind processes, may induce stochastic charge variations on the dust particles, which in turn lead to an orbit perturbation and spatial diffusion. It is suggested that the extent of the E ring and the braided, kinky structure of certain portions of the F rings as well as possible time variations are a result of plasma induced electromagnetic perturbations and drag forces. The G ring, in this scenario, requires some form of shepherding and should be akin to the F ring in structure. Sputtering of micron-sized dust particles in the E ring by magnetospheric ions yields lifetimes of 102to 104years. This effect as well as the plasma induced transport processes require an active source for the E ring, probably Enceladus.

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Analytical Electron Microscopy Characterization of Electric Arc Furnace Dust

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100097326 ◽

1981 ◽

Vol 39 ◽

pp. 134-135

Author(s):

J. R. Porter ◽

J. I. Goldstein ◽

D. B. Williams

Keyword(s):

Electron Microscopy ◽

Analytical Electron Microscopy ◽

Electric Arc Furnace ◽

Electric Arc ◽

Dust Particles ◽

Particle Analysis ◽

Arc Furnace ◽

Analytical Electron ◽

Residual Elements ◽

Industry Practice

Alloy scrap metal is increasingly being used in electric arc furnace (EAF) steelmaking and the alloying elements are also found in the resulting dust. A comprehensive characterization program of EAF dust has been undertaken in collaboration with the steel industry and AISI. Samples have been collected from the furnaces of 28 steel companies representing the broad spectrum of industry practice. The program aims to develop an understanding of the mechanisms of formation so that procedures to recover residual elements or recycle the dust can be established. The multi-phase, multi-component dust particles are amenable to individual particle analysis using modern analytical electron microscopy (AEM) methods.Particles are ultrasonically dispersed and subsequently supported on carbon coated formvar films on berylium grids for microscopy. The specimens require careful treatment to prevent agglomeration during preparation which occurs as a result of the combined effects of the fine particle size and particle magnetism. A number of approaches to inhibit agglomeration are currently being evaluated including dispersal in easily sublimable organic solids and size fractioning by centrifugation.

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Improving soil remediation through characterization

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100138300 ◽

1995 ◽

Vol 53 ◽

pp. 386-387

Author(s):

E. C. Buck ◽

N. L. Dietz ◽

J. K. Bates

Keyword(s):

Dust Particles ◽

Radiochemical Analysis ◽

Solid Product ◽

Uranium Contamination ◽

Physical Separation ◽

X Ray ◽

Rocky Flats ◽

Remediation Strategies ◽

Bearing Materials ◽

X Ray Absorption

Operations at former weapons processing facilities in the U. S. have resulted in a large volume of radionuclidecontaminated soils and residues. In an effort to improve remediation strategies and meet environmental regulations, radionuclide-bearing particles in contaminant soils from Fernald in Ohio and the Rocky Flats Plant (RFP) in Colorado have been characterized by electron microscopy. The object of these studies was to determine the form of the contaminant radionuclide, so that it properties could be established [1]. Physical separation and radiochemical analysis determined that uranium contamination at Fernald was not present exclusively in any one size/density fraction [2]. The uranium-contamination resulted from aqueous and solid product spills, air-borne dust particles, and from the operation of an incinerator on site. At RFP the contamination was from the incineration of Pu-bearing materials. Further analysis by x-ray absorption spectroscopy indicated that the majority of the uranium was in the 6+ oxidation state [3].

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