Soil erosion due to rainfall impact with no inflow: a numerical solution with spatial and temporal effects of sediment settling velocity characteristics

Based on the experimental data of sediment particle cloud during the settlement process in the water and combined with the existed sediment settling velocity formulae, a new formula for calculation of the settling velocity of sediment particle cloud is proposed by the introduction of the characteristic particle size of sediment particle cloud ( D' ). By using experimentally measured settling velocity values of sediment particle cloud to verify the settling velocity values of sediment particle cloud which calculated by using this new formula, the results show that the calculated settling velocity values using this new formula are closer to the experimental values.

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A test of the ADV-based Reynolds flux method for in situ estimation of sediment settling velocity in a muddy estuary

Geo-Marine Letters ◽

10.1007/s00367-013-0340-4 ◽

2013 ◽

Vol 33 (6) ◽

pp. 477-484 ◽

Cited By ~ 17

Author(s):

Grace M. Cartwright ◽

Carl T. Friedrichs ◽

S. Jarrell Smith

Keyword(s):

Settling Velocity ◽

Flux Method ◽

Sediment Settling

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Kapuas River sediment settling velocity analysis with withdrawal tube

IOP Conference Series Materials Science and Engineering ◽

10.1088/1757-899x/852/1/012038 ◽

2020 ◽

Vol 852 ◽

pp. 012038

Author(s):

W A Pranoto ◽

J Johan ◽

P Vinsensisus

Keyword(s):

River Sediment ◽

Settling Velocity ◽

Velocity Analysis ◽

Sediment Settling

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Discussion of Muddy Surface Settling of Xiaolangdi Reservoir

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.641-642.267 ◽

2014 ◽

Vol 641-642 ◽

pp. 267-270

Author(s):

Si Qi Jiang ◽

Jun Hua Zhang ◽

Guo Ming Gao ◽

Hong Wei Wang ◽

Tao Li

Keyword(s):

Calculation Method ◽

Sediment Sample ◽

Fine Particle ◽

Settling Velocity ◽

Water Concentration ◽

Sediment Distribution ◽

Curve Method ◽

Settling Section ◽

Xiaolangdi Reservoir ◽

Sediment Settling

Sediment settling velocity is an important parameter in particle suspension and indispensable link of hyperconcentrated flow as well as basic theory support for efficient sediment transport of Xiaolangdi Reservoir. This paper has adopted current sediment sample in Xiaolangdi Reservoir to take still water settling experiment, observed carefully silt sediment distribution during different settling duration under various initial concentrations, analyzed common settling velocity calculation method, and adopted settling duration curve method as calculation method to obtain a constant settling velocity of free settling section. Typical settling velocity that is obtained from experiments makes supplement and fitness to settling velocity formula of the existing groups of sediment sample, amends the formula coefficient, further explore the settling characteristics and settling velocity of fine particle mixed viscous sediment with water concentration change, and meanwhile this paper researched settling distance impact on settling velocity, existing sediment group settling transition to mesh settling critical transition silt concentration of Xiaolangdi Reservoir.

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Measurement of soil aggregate settling velocities. 1. A modified bottom withdrawal tube method

Soil Research ◽

10.1071/sr9880055 ◽

1988 ◽

Vol 26 (1) ◽

pp. 55 ◽

Cited By ~ 29

Author(s):

CJ Lovell ◽

CW Rose

Keyword(s):

Entire Range ◽

Settling Velocity ◽

Soil Aggregates ◽

Soil Aggregate ◽

Natural Sediment ◽

Polydisperse Suspension ◽

Modified Method ◽

Sediment Types ◽

Settling Velocity Distribution ◽

Sediment Settling

Sediment eroded by water consists largely of soil aggregates. The settling velocity of such aggregates and primary soil particles is of fundamental importance to the processes of sediment transport and deposition in water. A modified bottom withdrawal tube method is presented for the direct measurement of the settling velocity distribution of soil aggregates or particles of different sizes that settle together in a polydisperse suspension. The modified method overcomes experimental error and analytical deficiencies present in the initial method and is suitable for measuring settling velocities up to 0.5 m s-1. The method employs the bottom withdrawal principle; new exact theory is presented for interpretation of sedimentation data thus measured. By complementing the pipette or hydrometer methods which measure settling velocities less than 10-3 ms-1, this modified method allows analysis of the entire range of settling velocities encountered in natural sediment. Settling velocity distributions measured for a variety of sediment types are illustrated.

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Influence of flocculation on sediment deposition process at the Three Gorges Reservoir

Water Science & Technology ◽

10.2166/wst.2015.562 ◽

2015 ◽

Vol 73 (4) ◽

pp. 873-880 ◽

Cited By ~ 3

Author(s):

Dangwei Wang ◽

Xiaofang Liu ◽

Zuwen Ji ◽

Zhandi Dong ◽

Haihua Hu

Keyword(s):

Particle Size ◽

Deposition Rate ◽

Three Gorges Reservoir ◽

Settling Velocity ◽

Sediment Deposition ◽

Three Gorges ◽

Single Particles ◽

The Three Gorges Reservoir ◽

The Three Gorges ◽

Sediment Settling

By comparing the original particle gradation of sediment from the Three Gorges Reservoir with the single particle gradation, the differences in these two particle gradations showed that there is sediment flocculation in the Three Gorges Reservoir, which can accelerate the sediment deposition rate in the reservoir. In order to determine the influence of flocculation on the sediment settling velocity, sediment was collected at the Three Gorges Reservoir, and the indoor quiescent settling experiment was performed to study the mechanism of sediment flocculation. The experimental results showed that sediments aggregated from single particles into floccules in the settling processes. The single particles smaller than 0.022 mm will participate in the formation of floccules, which accounts for 83% of the total amount of sediment in the Three Gorges Reservoir. Moreover, the degree of sediment flocculation and the increase in sediment settling velocity were directly proportional to the sediment concentration. Taking the average particle size and the median particle size as the representative particle size, respectively, the maximum flocculation factors were calculated to be 3.4 and 5.0. Due to the sediment flocculation, the volume of sediment deposition will increase by 66% when the mass settling flux factor of total sediment had a maximum value of 1.66, suggesting that flocculation has a significant influence on the sediment deposition rate in the Three Gorges Reservoir.

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TURBIDITY - SEDIMENTATION IN CLOSED-END CHANNELS

Coastal Engineering Proceedings ◽

10.9753/icce.v20.98 ◽

1986 ◽

Vol 1 (20) ◽

pp. 98

Author(s):

Chung-Po Lin ◽

Jonathon W. Lott ◽

Ashish J. Mehta

Keyword(s):

Exponential Type ◽

Settling Velocity ◽

Gravity Currents ◽

Turbidity Current ◽

Main Channel ◽

Turbidity Currents ◽

Test Results ◽

Fine Grained ◽

Gate Opening ◽

Sediment Settling

In order to investigate the mechanism by which turbidity currents cause sedimentation in closed-end channels such as pier slips or residential canals, a laboratory investigation using fine-grained sediments was carried out. Two similar flume systems were used, each consisting of a main channel carrying sediment-laden flow and an orthogonally placed closed-end channel with a gate at the entrance. Characteristics of the turbidity current and sediment deposition in the closed-end channel were investigated following gate opening. Behavioral similarities between turbidity current and non-settling gravity currents were observed. Several properties, e.g. suspension concentration, showed exponential-type decay with distance. The ratio of sediment settling velocity to the densimetric velocity was found to be a useful parameter for comparing different test results. A relationship for estimating the sediment influx through the entrance is presented.

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