2016-9-27 · • Contact erosion under oscillatory flow perpendicular to the interface • Pore pressure distribution under perpendicular oscillatory flow • Incipient motion/transport of base material, including internal erosion • Design approach for the combination of oscillatory and unidirectional flow
2019-5-23 · 9. Mechanic mechanisms of wind-blown sand movement and quantitative evaluation of wind erosion (G2000048702), Major state basic research development program of China (973 program), 2000.01-2004.12, PI
2013-2-25 · The sand movement could also play an important role in environmental problems ranging from soil erosion, ... Electrification of granular systems of identical insulators. ... sand transport for ...
2014-7-7 · The electrification of sand particles is a universal phenomenon in wind-blown sand, and it plays an important role in the lifting and transport of sand particles. The charge-to-mass ratio of saltating particles is an important parameter to characterize the sand electrification.
2011-9-16 · N.B., Remember the distinction between erosion-corrosionand erosion: • erosion is the straightforward wearing away by the mechanical abrasion caused by suspended particles . ..e.g., sand-blasting,erosion ofturbine blades by droplets . .. • erosion-corrosion also involves a corrosive environment . ..the metal undergoes a chemical reaction.
2011-12-20 · The supply of sand to the watered rails increases the coupling coefficient by 12,9%, with a decrease in slip by 23,8% (Fig. 7). When supplying sand to the oiled rails, the coupling coefficient increases by 31%, the slip is reduced by 37% (Fig. 8). The supply of …
2017-3-27 · Triboelectric, or frictional, charging is a ubiquitous yet poorly understood phenomenon in granular flows. Recognized in terrestrial volcanic plumes and sand storms, such electrification ...
2019-10-25 · Moreover, sand transport can cause erosion and corrosion problems as a result of the impact on the pipe wall and the microbial attack under the sand bed. In addition, the slurry flow containing sands could lead to equipment failure. Therefore, the …
2010-1-29 · Results are presented of a series of experiments in which were measured: the mean critical bed shear stress at SHIELDS'' grain-movement condition and at the initiation of non-ceasing scour, the rate of bedload transport, the average particle velocity, the rate of deposition, and the average length of individual steps of saltating bed-load particles, in water, as a function of the time-mean bed ...
2011-4-7 · Seepage erosion of channel on a granular bed by rainfall Experiments : Michael Berhanu and Arshad Kudrolli (Clark University) Assistance from Joshua Meyer, Fouad Abdelameer ... flat layer of sand V Transport of beads by surface flow Progressively a channel is dug . Experimental device Deformation of a laser line swept on the surface
2021-8-19 · Suffusion, transport and filtration of fine particles in granular soil Didier Marot, Ahmed Benamar To cite this version: Didier Marot, Ahmed Benamar. Suffusion, transport and filtration of fine particles in granular soil. Erosion of geomaterials, pp.39-79, 2012, 10.1002/9781118561737 2. hal-01007547
2021-2-2 · "Sand, rice, sugar, snow, cement ... Although ubiquitous in our daily lives, granular media still challenge engineers and fascinate researchers. This book provides the state of the art of the physics of granular media and recent advances in the field. The book presents the fundamental properties of granular materials: interactions between grains; solid, liquid and gaseous behaviours; coupling ...
Abstract. Motivated by examples of erosive incision of channels in sand, we investigate the motion of individual grains in a granular bed driven by a laminar fluid to give us new insights into the relationship between hydrodynamic stress and surface granular flow. A closed cell of rectangular cross-section is partially filled with glass beads ...
2014-2-27 · The electrification of wind-blown sand has been widely confirmed by field and wind-tunnel measurements. It plays an important role in the lifting and transport of sand particles. In this study we investigated the behavior of electric fields in unsteady saltation by …
2017-12-20 · Soil erosion by water is the detachment, transport and deposition of soil particles by flowing water. After intense rainfall and runoff events, it can take the form of concentrated ... Cropland soils with a high silt and very fine sand content on long, soil surface protect soil. steep slopes are at the highest risk of erosion by water.
2012-6-1 · The transport of granular materials by wind has a major impact on our environment through sand/soil erosion and the generation and transport of atmospheric dust aerosols. Terrestrially the transport of dust involves billions of tons of material every year, influencing the global climate and impacting directly upon human health.
Particle electrification not only occurs during the wind-blown transport of dust and sand, but appears to be general to granular systems of chemically identical insulating particles.
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2019-4-23 · Gravel is a granular material derived from the erosion of rocks, ranging in size from 4.75 mm to 75 mm. Gravel particles are larger than sand but smaller than boulders. Erosion''s effect on size: Erosion is the gradual destruction of a landform …
2011-12-30 · Internal erosion (IE) affects the stability of natural and reinforced materials by causing instability within their granular structure. The dislodgement and transport of eroded particles affect both the particulate concentration of eroding fluid and the pore network of eroded material.
2009-5-18 · Insulating particles can become highly electrified during powder handling, volcanic eruptions, and the wind-blown transport of dust, sand, and snow. Measurements in these granular systems have found that smaller particles generally charge negatively, while larger particles charge positively. These observations are puzzling since particles in these systems are generally chemically identical and ...
2006-2-27 · the loamy sand decreased final IR from 14 to 2 mm h21 and increased runoff and wash erosion in the control; similar trends but of different magnitude were noted in the other soil types. Spreading PAM mixed with PG or PG alone was effective in maintaining final IR . 12 mm h21, low runoff, and wash erosion levels compared with their control.
2021-9-23 · Sand is a mixture of small grains of rock and granular materials which is mainly defined by size, being finer than gravel and coarser than silt. And ranging in size from 0.06 mm to 2 mm.Particles which are larger than 0.0078125 mm but smaller than 0.0625 mm are termed silt.. Sand is made by erosion or broken pebbles and weathering of rocks, which is carried by seas or rivers.
Particle electrification not only occurs during the wind-blown transport of dust and sand, but appears to be general to granular systems of chemically identical insulating particles. Measurements have generally reported that smaller particles in these systems charge negatively, while larger particles charge positively.
2012-5-22 · Influence of Sand Fines Transport Velocity on Erosion-Corrosion Phenomena of Carbon Steel 90-Degree Elbow 11 May 2020 | Metals, Vol. 10, No. 5 Investigation of granular dispersion in turbulent pipe flows with electrostatic effect
Abstract A CFD model has been implemented to investigate the effects the pipe undulation on sand transport. Of particular interest of the present study is the sand deposition in small angled V-inclined bend relevant to oil and gas subsea flowlines where sand deposition could be a major problem. The model used is the two-fluid Eulerian-Eulerian model with the granular temperature to tackle the ...
Abstract. The transport of granular materials by wind has a major impact on our environment through sand/soil erosion and the generation and transport of atmospheric dust aerosols. Terrestrially the transport of dust involves billions of tons of material every year, influencing the global climate and impacting directly upon human health.
2018-6-26 · areas and positive in areas of erosion. Electrification in aeolian processes is also a factor in the interparticle forces that deter- mine threshold wind speeds at which particles begin to move [Greeley and Iversen, 1985]. Summarizing, from previous work on sand and by analogy with blowing snow, we expected wind-blown sand to develop
· The transport of granular materials by wind has a major impact on our environment through sand/soil erosion and the generation and transport of atmospheric dust aerosols. Terrestrially the transport of dust involves billions of tons of material every year, influencing the global climate and impacting directly upon human health. Research in aeolian transport involves the inter-related fields of ...
2019-9-30 · Erosion of the soil fine particles is one of major engineering challengings in coastal and off-shore structures projects. Erosion is the reac-tion to an external forces exerted on the soil. Current, waves, waves-induced actions or a combination of all, is the force which leads to erosion. Many measures are used to keep the structure
Abstract. Dust and sand electrification, which is a ubiquitous phenomenon in dust events, has a potentially dramatic effect on dust and sand lifting and transport processes. However, the effect of such electrification is still largely unclear, mainly due to its …
The transport of granular materials by wind has a major impact on our environment through sand/soil erosion and the generation and transport of atmospheric dust aerosols.
2013-7-20 · 7 Immersed granular media 285 7.1 Two-phase flow equations 285 7.2 The role of the fluid in static piles 290 7.3 The role of the interstitial fluid during changes of volume fraction 294 7.4 The role of fluid in granular flows 303 8 Erosion and sediment transport 311 8.1 Introduction 311 8.2 The static transport threshold 313
particles, streamwise sand transport flux, sand ejecta flux, and wind velocity profile, etc., which are concerned in the research of either mechanism of wind-blown sand or wind erosion. From the simulation results, finally, the effect of electrification on the saltation motion of sand is discussed quantitatively. 2. Experimental Apparatus