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Suspended Load
The suspended load of a flow of fluid, such as a river, is the portion of its sediment uplifted by the fluid's flow in the process of sediment transportation. It is kept suspended by the fluid's turbulence. The suspended load generally consists of smaller particles, like clay, silt, and fine sands''.'' Sediment transportation The suspended load is one of the three layers of the fluvial sediment transportation system. The bed load consists of the larger sediment which is transported by saltation, rolling, and dragging on the riverbed. The suspended load is the middle layer that consists of the smaller sediment that's suspended. The wash load is uppermost layer which consist of the smallest sediment that can be seen with the naked eye; however, the wash load gets easily mixed with suspended load during transportation due to the very similar process. The wash load never touches the bed even outside of a current. Composition The boundary between bed load and suspended load ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fluid
In physics, a fluid is a liquid, gas, or other material that continuously deforms (''flows'') under an applied shear stress, or external force. They have zero shear modulus, or, in simpler terms, are substances which cannot resist any shear force applied to them. Although the term ''fluid'' generally includes both the liquid and gas phases, its definition varies among branches of science. Definitions of ''solid'' vary as well, and depending on field, some substances can be both fluid and solid. Viscoelastic fluids like Silly Putty appear to behave similar to a solid when a sudden force is applied. Substances with a very high viscosity such as pitch appear to behave like a solid (see pitch drop experiment) as well. In particle physics, the concept is extended to include fluidic matters other than liquids or gases. A fluid in medicine or biology refers any liquid constituent of the body (body fluid), whereas "liquid" is not used in this sense. Sometimes liquids given for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wash Load
Wash load is similar to a suspended load, but wash load sediment never interacts with the bed load. All of the sediment in the wash load stays suspended in the water throughout the channel (this concept has been debated). Wash load refers to a river's ability to move sediment through a channel. Hans Albert Einstein described wash load as "if the sediment is added to the upstream end of a concrete channel and the channel is swept clean, and the sediment has not left any trace in the channel". The sediments in the wash load are generally smaller than .0625 mm. What determines the wash load is the relationship between the size of the bed load and the size of the particles that never settle in the "fine sediment load" or wash load. Composition Composition is a good way to classify the difference between wash and bed loads because the definition is distinct. The wash load is almost entirely made up of grains that are not found in quantity in the bed. Wash load grains tend to be v ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wash Load
Wash load is similar to a suspended load, but wash load sediment never interacts with the bed load. All of the sediment in the wash load stays suspended in the water throughout the channel (this concept has been debated). Wash load refers to a river's ability to move sediment through a channel. Hans Albert Einstein described wash load as "if the sediment is added to the upstream end of a concrete channel and the channel is swept clean, and the sediment has not left any trace in the channel". The sediments in the wash load are generally smaller than .0625 mm. What determines the wash load is the relationship between the size of the bed load and the size of the particles that never settle in the "fine sediment load" or wash load. Composition Composition is a good way to classify the difference between wash and bed loads because the definition is distinct. The wash load is almost entirely made up of grains that are not found in quantity in the bed. Wash load grains tend to be v ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bed Load
The term bed load or bedload describes particles in a flowing fluid (usually water) that are transported along the stream bed. Bed load is complementary to suspended load and wash load. Bed load moves by rolling, sliding, and/or saltating (hopping). Generally, bed load downstream will be smaller and more rounded than bed load upstream (a process known as downstream fining). This is due in part to attrition and abrasion which results from the stones colliding with each other and against the river channel, thus removing the rough texture (rounding) and reducing the size of the particles. However, selective transport of sediments also plays a role in relation to downstream fining: smaller-than average particles are more easily entrained than larger-than average particles, since the shear stress required to entrain a grain is linearly proportional to the diameter of the grain. However, the degree of size selectivity is restricted by the hiding effect described by Parker and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sediment Transport
Sediment transport is the movement of solid particles (sediment), typically due to a combination of gravity acting on the sediment, and/or the movement of the fluid in which the sediment is entrained. Sediment transport occurs in natural systems where the particles are clastic rocks (sand, gravel, boulders, etc.), mud, or clay; the fluid is air, water, or ice; and the force of gravity acts to move the particles along the sloping surface on which they are resting. Sediment transport due to fluid motion occurs in rivers, oceans, lakes, seas, and other bodies of water due to currents and tides. Transport is also caused by glaciers as they flow, and on terrestrial surfaces under the influence of wind. Sediment transport due only to gravity can occur on sloping surfaces in general, including hillslopes, scarps, cliffs, and the continental shelf—continental slope boundary. Sediment transport is important in the fields of sedimentary geology, geomorphology, civil engineering, hy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sediment
Sediment is a naturally occurring material that is broken down by processes of weathering and erosion, and is subsequently transported by the action of wind, water, or ice or by the force of gravity acting on the particles. For example, sand and silt can be carried in suspension in river water and on reaching the sea bed deposited by sedimentation; if buried, they may eventually become sandstone and siltstone ( sedimentary rocks) through lithification. Sediments are most often transported by water ( fluvial processes), but also wind (aeolian processes) and glaciers. Beach sands and river channel deposits are examples of fluvial transport and deposition, though sediment also often settles out of slow-moving or standing water in lakes and oceans. Desert sand dunes and loess are examples of aeolian transport and deposition. Glacial moraine deposits and till are ice-transported sediments. Classification Sediment can be classified based on its grain size, grain s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shear Stress
Shear stress, often denoted by (Greek: tau), is the component of stress coplanar with a material cross section. It arises from the shear force, the component of force vector parallel to the material cross section. ''Normal stress'', on the other hand, arises from the force vector component perpendicular to the material cross section on which it acts. General shear stress The formula to calculate average shear stress is force per unit area.: : \tau = , where: : = the shear stress; : = the force applied; : = the cross-sectional area of material with area parallel to the applied force vector. Other forms Wall shear stress Wall shear stress expresses the retarding force (per unit area) from a wall in the layers of a fluid flowing next to the wall. It is defined as: \tau_w:=\mu\left(\frac\right)_ Where \mu is the dynamic viscosity, u the flow velocity and y the distance from the wall. It is used, for example, in the description of arterial blood flow in which case which t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reynolds Number
In fluid mechanics, the Reynolds number () is a dimensionless quantity that helps predict fluid flow patterns in different situations by measuring the ratio between inertial and viscous forces. At low Reynolds numbers, flows tend to be dominated by laminar (sheet-like) flow, while at high Reynolds numbers flows tend to be turbulent. The turbulence results from differences in the fluid's speed and direction, which may sometimes intersect or even move counter to the overall direction of the flow (eddy currents). These eddy currents begin to churn the flow, using up energy in the process, which for liquids increases the chances of cavitation. The Reynolds number has wide applications, ranging from liquid flow in a pipe to the passage of air over an aircraft wing. It is used to predict the transition from laminar to turbulent flow and is used in the scaling of similar but different-sized flow situations, such as between an aircraft model in a wind tunnel and the full-size v ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hjulström Curve
The Hjulström curve, named after Filip Hjulström (1902–1982), is a graph used by hydrologists and geologists to determine whether a river will erode, transport, or deposit sediment. It was originally published in his doctoral thesis "Studies of the morphological activity of rivers as illustrated by the River Fyris.Hjulstrom, F. (1935). Studies of the morphological activity of rivers as illustrated by the River Fyris, Bulletin. Geological Institute Upsalsa, 25, 221-527." in 1935. The graph takes sediment particle size and water velocity into account.Sediment transportation Last accessed 26 Dec 2011. The upper curve shows the critical erosion velocity in cm/s as a function of particle size in mm, while the lower curve shows the deposition velocity as a function of particle size. Note that the axes are [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
My Own Hjulstrum
My or MY may refer to: Arts and entertainment * My (radio station), a Malaysian radio station * Little My, a fictional character in the Moomins universe * ''My'' (album), by Edyta Górniak * ''My'' (EP), by Cho Mi-yeon Business * Marketing year, variable period * Model year, product identifier Transport * Motoryacht * Motor Yacht, a name prefix for merchant vessels * Midwest Airlines (Egypt), IATA airline designation * MAXjet Airways, United States, defunct IATA airline designation Other uses * ''My'', the genitive form of the English pronoun ''I'' * Malaysia, ISO 3166-1 country code ** .my, the country-code top level domain (ccTLD) * Burmese language (ISO 639 alpha-2) * Megalithic Yard, a hypothesised, prehistoric unit of length * Million years See also * MyTV (other) MyTV (or My TV) may refer to these television brands: Africa * MYtv, a South African TV channel Asia *Television Broadcasts Limited's online service in Hong Kong * My TV (Bangladeshi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rouse Number
The Rouse number (P or Z) is a non-dimensional number in fluid dynamics which is used to define a concentration profile of suspended sediment and which also determines how sediment will be transported in a flowing fluid. It is a ratio between the sediment fall velocity w_s and the upwards velocity on the grain as a product of the von Kármán constant \kappa and the shear velocity u_*. :\mathrm = \frac Occasionally the factor β is included before the von Kármán constant in the equation, which is a constant which correlates eddy viscosity to eddy diffusivity. This is generally taken to be equal to 1, and therefore is ignored in actual calculation. However, it should not be ignored when considering the full equation. :\mathrm = \frac It is named after the American fluid dynamicist Hunter Rouse. It is a characteristic scale parameter in the Rouse Profile of suspended sediment concentration with depth in a flowing fluid. The concentration of suspended sediment with depth goes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fluvial
In geography and geology, fluvial processes are associated with rivers and streams and the deposits and landforms created by them. When the stream or rivers are associated with glaciers, ice sheets, or ice caps, the term glaciofluvial or fluvioglacial is used. Fluvial processes Fluvial processes include the motion of sediment and erosion or deposition on the river bed. The movement of water across the stream bed exerts a shear stress directly onto the bed. If the cohesive strength of the substrate is lower than the shear exerted, or the bed is composed of loose sediment which can be mobilized by such stresses, then the bed will be lowered purely by clearwater flow. In addition, if the river carries significant quantities of sediment, this material can act as tools to enhance wear of the bed ( abrasion). At the same time the fragments themselves are ground down, becoming smaller and more rounded ( attrition). Sediment in rivers is transported as either bedload (the coarser fr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
