Статті в журналах: "Einstein's sediment transport parameters"

1

Okoli, C. S., S. I. A. Ojo, and A. M. Oguntuase. "Modelling of Sediment Transport Capacities of Ogbese and Owena Rivers in S.W. Nigeria." Advanced Materials Research 62-64 (February 2009): 786–96. http://dx.doi.org/10.4028/www.scientific.net/amr.62-64.786.

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The movement of sediment such as sand, silt or gravel by flowing water is of interest to a wide range of engineering disciplines. This study is aimed at developing models, which can be used to predict the magnitude and levels of sediment concentration in Ogbese and Owena Rivers in Ondo State S.W. Nigeria for engineering design purposes. Data were collected from field investigations conducted at the respective sampling stations on the two rivers. The live bed concept used was derived from Liu – Hwang (1954) resistance equations and that of Einstein-Brown (1981) sediment transport concept. The problem was reduced to that of a power law relationship. These data ere fitted into the power relationship to obtain the predicted model of the form: F1Q = k2k1, where the parameters F1Q is the dimensionless sediment discharge,  is the dimensionless bed shear stress, k1 and k2 are sediments transport coefficients. Calibrating the models yielded the values of k1 and k2 for Ogbese river as 0.592 and 0.865 and for Owena river as 0.335 and 1.197 respectively. When tested the predicted models for Ogbese and Owena rivers performed well in comparison with the established models such as Ackers and White (1973), Engleund and Hansen (1967), Yang (1973) a\and Karim (1998). It is concluded that the models developed would be useful for engineering design purposes for Ogbese and Owena rivers.

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2

Guseinov, I. I., and B. A. Mamedov. "Use of complete gamma function in accurate evaluation of Einstein integrals." Hydrology Research 39, no. 3 (June 1, 2008): 223–27. http://dx.doi.org/10.2166/nh.2008.042.

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By the use of the binomial expansion theorem, the series expansion relations in terms of the complete gamma function are obtained for Einstein integrals arising in the hydraulic and modern sediment transport mechanics. The approach presented for Einstein integrals is accurate enough over the whole range of parameters. The computational time for calculation of the series with respect to the literature is fast. Furthermore, the comparison of the method with numerical calculations demonstrates the applicability and accuracy of the method.

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3

Kleijwegt, Rob A., Robin G. Veldkamp, and Chandra Nalluri. "Sediment in Sewers: Initiation of Transport." Water Science and Technology 22, no. 10-11 (October 1, 1990): 239–46. http://dx.doi.org/10.2166/wst.1990.0310.

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The initiation of sediment transport in sewers was investigated in field and laboratory studies. From the field studies it was concluded that some deposits in sewers are permanent due to the insufficient capability of the flow to erode the deposits. From the laboratory studies it was concluded that the upper limit of the critical shear stresses for cohesive sewer sediments may not exceed 5-7 N/m2. Non-cohesive sediments are eroded at lower shear stresses than predicted by Shields' criterion. The shear stresses were calculated using the general equations of continuity and motion and Einstein's separation technique for channels of compound roughness. Experiments showed the validity of this method.

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4

Akbari, G. "Optimising flow–sediment transport parameters for rivers." Proceedings of the Institution of Civil Engineers - Water Management 160, no. 3 (September 2007): 153–58. http://dx.doi.org/10.1680/wama.2007.160.3.153.

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5

Syvitski, James P., Mark D. Morehead, David B. Bahr, and Thierry Mulder. "Estimating fluvial sediment transport: The rating parameters." Water Resources Research 36, no. 9 (September 2000): 2747–60. http://dx.doi.org/10.1029/2000wr900133.

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6

Yalin, S., and R. C. H. Russell. "SIMILARITY IN SEDIMENT TRANSPORT DUE TO WAVES." Coastal Engineering Proceedings 1, no. 8 (January 29, 2011): 12. http://dx.doi.org/10.9753/icce.v8.12.

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The paper concerns the movement by waves of cohesionless sediment lying on a horizontal bed. In particular it concerns the number of dimensionless parameters that are necessary to define the 2-phase motion at the bed; the specification of which would enable perfect similarity to be obtained. It is shown that in general four dimensionless parameters are necessary but that when the motion of the water at the bed can be adequately defined by an orbit length (a) and a period (T), the two-phase motion can be described by the numerical value of three dimensionless parameters. This condition is satisfied when the wave-height is low, because then the orbital motion at the bed is sinusoidal and the drift velocity is negligible. Model and prototype experiments were conducted in a wave channel, using low waves, in which the scale for depth of water and for wavelengths was -37?. The dependent parameters, three of -which are sufficient to verify similarity of all aspects of the phenomenon were chosen to be ripple height, ripple length and transport of sediment. The identity of the dimensionless numbers signifying the ripple height, ripple length and transport in model and prototype, shown in Figs, 8, 9 and 11, is proof that similarity had been obtained.

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7

Lepikhin, Anatoly P., and Anna A. Wozniak. "ON THE PROBLEM OF SEDIMENT TRANSPORT ASSESSMENT." Географический вестник = Geographical bulletin, no. 4(55) (2020): 125–36. http://dx.doi.org/10.17072/2079-7877-2020-4-125-136.

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The paper discusses the problem of high errors in the design ratios proposed for assessing sediment transport in natural watercourses. The question is why numerous empirical design ratios obtained and successfully used for some watercourses can give an error of 1000% when applied to other rivers. Calculation formulas worked out on hydraulic trays and channels are found to be inappropriate for specific rivers and natural channels. The problem is caused by the complexity of the natural watercourses geometry and the heterogeneity of the bottom sediment composition. Two approaches that are currently used in assessing the transporting capacity of river flows are studied in the paper. They were laid down in river hydraulics as early as the second half of the 18th century in the works by A. Chesi and P. Dubois. The conditions and possibilities of using both methods are considered and theoretically proven in the paper. The approach developed by P. Dubois is distinguished by a detailed study of the influence of individual factors based on numerous experimental models, the construction of fairly rigorous physical models on this basis, the complication of design ratios, the inclusion of new additional parameters. A. Chesi offered the construction of a maximally simplified initial physical model, with the calibration parameters established for specific conditions on the basis of field observations or qualitative estimates, and therefore being less accurate but more stable. It is shown that despite the scientific attractiveness of the approach to constructing and using more complex calculation models containing new additional parameters, the inclusion of additional parameters entails the inclusion of additional errors associated with the estimation of these parameters. The effectiveness of both approaches is proved; the application of one or the other approach is determined by the conditions and nature of the tasks to be solved, as well as the volume and accuracy of the initial data.

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8

Ahmad Abdul Ghani, Nadiatul Adilah, Junaidah Ariffin, and Duratul Ain Tholibon. "Robustness Analysis of Model Parameters for Sediment Transport Equation Development." ASM Science Journal 12 (July 22, 2019): 1–17. http://dx.doi.org/10.32802/asmscj.2019.268.

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Robustness analysis of model parameters for sediment transport equation development is carried out using 256 hydraulics and sediment data from twelve Malaysian rivers. The model parameters used in the analyses include parameters in equations by Ackers-White, Brownlie, Engelund-Hansen, Graf, Molinas-Wu, Karim-Kennedy, Yang, Ariffin and Sinnakaudan. Seven parameters in five parameter classes were initially tested. Robustness of the model parameters was measured on the statistical relations through Evolutionary Polynomial Regression (EPR) technique and further examined using the discrepancy ratio of the predicted versus the measured values. Results from analyses suggest (ratio of shear velocity to flow velocity) and (ratio of hydraulic radius to mean sediment diameter) to be the most significant and influential parameters for the development of sediment transport equation.

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9

le Roux, J. P., R. D. O’Brien, F. Rios, and M. Cisternas. "Analysis of sediment transport paths using grain-size parameters." Computers & Geosciences 28, no. 5 (June 2002): 717–21. http://dx.doi.org/10.1016/s0098-3004(01)00074-7.

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10

West, J. R., K. O. K. Oduyemi, A. J. Bale, and A. W. Morris. "The field measurement of sediment transport parameters in estuaries." Estuarine, Coastal and Shelf Science 30, no. 2 (February 1990): 167–83. http://dx.doi.org/10.1016/0272-7714(90)90062-v.

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11

Hung, Nguyen Manh. "Lateral turbulent mixing forces in the long shore current calculation by Longuet-Higgins method and their influence on long shore sediment transport." Vietnam Journal of Mechanics 25, no. 4 (December 31, 2003): 214–24. http://dx.doi.org/10.15625/0866-7136/25/4/6593.

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Longuet - Higgins method for long shore current and Bijker method for sediment transport calculations are worldwide used mathematical model in the coastal engineering. When using them, we should image how work the methods and what is sensitivity and influence of each parameters on final results as sediment transport. In this paper, the influences of parameters N, P of lateral turbulent mixing forces on the long shore current and then on the sediment transport are estimated. The Bijker example is used and the computation results are compared with Bijker results for neglecting the lateral turbulent mixing. A field application with appropriate parameters N and P for Le Thuy beach is obtained for verification of long shore current and sediment transport.

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12

Ali, M., G. Sterk, M. Seeger, M. Boersema, and P. Peters. "Effect of hydraulic parameters on sediment transport capacity in overland flow over erodible beds." Hydrology and Earth System Sciences 16, no. 2 (February 27, 2012): 591–601. http://dx.doi.org/10.5194/hess-16-591-2012.

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Abstract. Sediment transport is an important component of the soil erosion process, which depends on several hydraulic parameters like unit discharge, mean flow velocity, and slope gradient. In most of the previous studies, the impact of these hydraulic parameters on transport capacity was studied for non-erodible bed conditions. Hence, this study aimed to examine the influence of unit discharge, mean flow velocity and slope gradient on sediment transport capacity for erodible beds and also to investigate the relationship between transport capacity and composite force predictors, i.e. shear stress, stream power, unit stream power and effective stream power. In order to accomplish the objectives, experiments were carried out in a 3.0 m long and 0.5 m wide flume using four well sorted sands (0.230, 0.536, 0.719, 1.022 mm). Unit discharges ranging from 0.07 to 2.07 × 10−3 m2 s−1 were simulated inside the flume at four slopes (5.2, 8.7, 13.2 and 17.6%) to analyze their impact on sediment transport rate. The sediment transport rate measured at the bottom end of the flume by taking water and sediment samples was considered equal to sediment transport capacity, because the selected flume length of 3.0 m was found sufficient to reach the transport capacity. The experimental result reveals that the slope gradient has a stronger impact on transport capacity than unit discharge and mean flow velocity due to the fact that the tangential component of gravity force increases with slope gradient. Our results show that unit stream power is an optimal composite force predictor for estimating transport capacity. Stream power and effective stream power can also be successfully related to the transport capacity, however the relations are strongly dependent on grain size. Shear stress showed poor performance, because part of shear stress is dissipated by bed irregularities, bed form evolution and sediment detachment. An empirical transport capacity equation was derived, which illustrates that transport capacity can be predicted from median grain size, total discharge and slope gradient.

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13

Ali, M., G. Sterk, M. Seeger, M. P. Boersema, and P. Peters. "Effect of hydraulic parameters on sediment transport capacity in overland flow over erodible beds." Hydrology and Earth System Sciences Discussions 8, no. 4 (July 14, 2011): 6939–65. http://dx.doi.org/10.5194/hessd-8-6939-2011.

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Abstract. Sediment transport is an important component of the soil erosion process, which depends on several hydraulic parameters like unit discharge, mean flow velocity, and slope gradient. In most of the previous studies, the impact of these hydraulic parameters on transport capacity was studied for non-erodible bed conditions. Hence, this study aimed to examine the influence of unit discharge, mean flow velocity and slope gradient on sediment transport capacity for erodible beds and also to investigate the relationship between transport capacity and composite force predictors i.e. shear stress, stream power, unit stream power and effective stream power. In order to accomplish the objectives, experiments were carried out using four well sorted sands (0.230, 0.536, 0.719, 1.022 mm). Unit discharges ranging from 0.07 to 2.07 × 10−3 m2 s−1 were simulated inside the flume at four slopes (5.2, 8.7, 13.2 and 17.6 %) to analyze their impact on sediment transport rate. The sediment transport rate measured at the bottom end of the flume by taking water and sediment samples was considered equal to sediment transport capacity, because the selected flume length of 3.0 m was found sufficient to reach the transport capacity. The experimental result reveals that the slope gradient has a stronger impact on transport capacity than unit discharge and mean flow velocity due to the fact that the tangential component of gravity force increases with slope gradient. Our results show that unit stream power is an optimal composite force predictor for estimating transport capacity. Stream power and effective stream power can also be successfully related to the transport capacity, however the relations are strongly dependent on grain size. Shear stress showed poor performance, because part of shear stress is dissipated by bed irregularities, bed form evolution and sediment detachment. An empirical transport capacity equation was derived, which illustrates that transport capacity can be predicted from median grain size, total discharge and slope gradient.

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14

Harsanto, P., B. P. Kamiel, and Nursetiawan. "Identify the physical characteristics of bedload transport using accelerometer." IOP Conference Series: Earth and Environmental Science 930, no. 1 (December 1, 2021): 012035. http://dx.doi.org/10.1088/1755-1315/930/1/012035.

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Abstract Real-time sediment transport discharge monitoring in rivers is a challenge. One of the difficulties is the existence of the transport sediment on the bottom of the river bed, the water flow making it invisible to the naked eye, and the flow of velocity itself creates a barrier to measure and install devices in the river. Vibration-based sediment transport measuring instruments have been developed in developed countries. Only a few people in Indonesia have created a technique for quantifying transport sediment. The experiment was carried out in a flume with sediment of a specified diameter flowing through it. An accelerometer was installed at the bottom to measure the vibration induced by the sediment movement at the channel’s bottom. Impact energy is created when sediment grains collide with the channel’s bottom. The amount and size of the sediment determine how much energy is released. The accelerometer measures the amplitude of the vibration signal that is produced by the energy. The statistical parameters can be used with alternating quantities of data. The findings of the experiments reveal that the larger the parameters value linearly with the sediment grain size.

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15

Shibayama, Tomoya, Akihiko Higuchi, and Kiyoshi Horikawa. "SEDIMENT TRANSPORT DUE TO BREAKING WAVES." Coastal Engineering Proceedings 1, no. 20 (January 29, 1986): 111. http://dx.doi.org/10.9753/icce.v20.111.

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In the surf zone, the agitation of the bed materials by breaking waves is strong and the suspended sand concentration in the vicinity of the wave plunging point is extremely high. Sand movement in this region was observed and sand concentration was measured in a wave flume. The sand movement in the region was divided into the following two categories: 1) sand suspension due to the large vortex which is created by wave plunging, and 2) sand deposition under turbulent flow. The condition for exciting this suspension process was considered and the result was well explained by the two parameters which are the deep water wave steepness and the bottom slope. Then a numerical model of the sediment suspension process was formulated and the process was well simulated by the model.

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16

Zhang, Bin, Xing Nian Liu, and Feng Guang Yang. "Two Stochastic Fraction Bedload Transport Rate Models for Nonuniform Sediment." Applied Mechanics and Materials 295-298 (February 2013): 1894–97. http://dx.doi.org/10.4028/www.scientific.net/amm.295-298.1894.

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Based on a method stochastic processes, two new bedload transport models for the ith size fraction nonuniform sediment are theoretically developed by using a stochastic model of sediment exchange and the probabilistic distribution of fractional bedload transport rates. The relations, proposed recently by Yang, for the probability of fractional incipient motion and for the average velocity of particle motion are introduced to bedload formulas. Plenty of experimental data for the bedload transport rate of uniform sediment are used to determine parameters. Finally, the two models are verified with natural data expressing the transport of nonuniform sediment under full motion in laboratory flume. The result shows that the experimental observations agree well with the predicted fractional bedload transport rates. Comparison of the theory with field data shows that the proposed formula still applies to uniform sediment transportation condition as long as the relevant parameters for uniform sediment are taken into account.

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17

Luo, Feng, Li Li Ge, and De Yu Kong. "Determination of Correlation Parameters of Near-Bed Sediment Flux." Applied Mechanics and Materials 405-408 (September 2013): 1398–401. http://dx.doi.org/10.4028/www.scientific.net/amm.405-408.1398.

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It is difficult to solve the near-bed sediment flux of suspended sediment transport equation under the non-equilibrium condition by theory analysis and numerical calculation. There are many variances, empirical coefficients and expressions undetermined. Bed shear stress is active methods to determine near-bed sediment flux. By comparing and analyzing of the research achievements, this paper provided the parameters spans, formulas of the variances and their correlations for determining the sediment flux, in the hope of promoting the sediment research.

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18

Krishnappan, Bommanna. "Review of a Semi-Empirical Modelling Approach for Cohesive Sediment Transport in River Systems." Water 14, no. 2 (January 16, 2022): 256. http://dx.doi.org/10.3390/w14020256.

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In this paper, a review of a semi-empirical modelling approach for cohesive sediment transport in river systems is presented. The mathematical modelling of cohesive sediment transport is a challenge because of the number of governing parameters controlling the various transport processes involved in cohesive sediment, and hence a semi-empirical approach is a viable option. A semi-empirical model of cohesive sediment called the RIVFLOC model developed by Krishnappan is reviewed and the model parameters that need to be determined using a rotating circular flume are highlighted. The parameters that were determined using a rotating circular flume during the application of the RIVFLOC model to different river systems include the critical shear stress for erosion of the cohesive sediment, critical shear stress for deposition according to the definition of Partheniades, critical shear stress for deposition according to the definition of Krone, the cohesion parameter governing the flocculation of cohesive sediment and a set of empirical parameters that define the density of the floc in terms of the size of the flocs. An examination of the variability of these parameters shows the need for testing site-specific sediments using a rotating circular flume to achieve a reliable prediction of the RIVFLOC model. Application of the model to various river systems has highlighted the need for including the entrapment process in a cohesive sediment transport model.

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19

Jaffe, Bruce, Kazuhisa Goto, Daisuke Sugawara, Guy Gelfenbaum, and SeanPaul La Selle. "Uncertainty in Tsunami Sediment Transport Modeling." Journal of Disaster Research 11, no. 4 (August 1, 2016): 647–61. http://dx.doi.org/10.20965/jdr.2016.p0647.

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Erosion and deposition from tsunamis record information about tsunami hydrodynamics and size that can be interpreted to improve tsunami hazard assessment. We explore sources and methods for quantifying uncertainty in tsunami sediment transport modeling. Uncertainty varies with tsunami, study site, available input data, sediment grain size, and model. Although uncertainty has the potential to be large, published case studies indicate that both forward and inverse tsunami sediment transport models perform well enough to be useful for deciphering tsunami characteristics, including size, from deposits. New techniques for quantifying uncertainty, such as Ensemble Kalman Filtering inversion, and more rigorous reporting of uncertainties will advance the science of tsunami sediment transport modeling. Uncertainty may be decreased with additional laboratory studies that increase our understanding of the semi-empirical parameters and physics of tsunami sediment transport, standardized benchmark tests to assess model performance, and development of hybrid modeling approaches to exploit the strengths of forward and inverse models.

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20

Demirci, Mustafa, and M. Sami Akoz. "Investigation of bar parameters occurred by cross-shore sediment transport." International Journal of Naval Architecture and Ocean Engineering 5, no. 2 (June 30, 2013): 277–86. http://dx.doi.org/10.3744/jnaoe.2013.5.2.277.

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21

Demirci, Mustafa, and M. Sami Aköz. "Investigation of bar parameters occurred by cross-shore sediment transport." International Journal of Naval Architecture and Ocean Engineering 5, no. 2 (June 2013): 277–86. http://dx.doi.org/10.2478/ijnaoe-2013-0132.

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22

Rose, Christopher P., and Peter D. Thorne. "Measurements of suspended sediment transport parameters in a tidal estuary." Continental Shelf Research 21, no. 15 (October 2001): 1551–75. http://dx.doi.org/10.1016/s0278-4343(00)00087-x.

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23

Elghannay, Husam A., and Danesh K. Tafti. "Sensitivity of numerical parameters on DEM predictions of sediment transport." Particulate Science and Technology 36, no. 4 (December 27, 2017): 438–46. http://dx.doi.org/10.1080/02726351.2017.1352638.

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24

Nalluri, C., A. Ab Ghani, and A. K. S. El-Zaemey. "Sediment Transport over Deposited Beds in Sewers." Water Science and Technology 29, no. 1-2 (January 1, 1994): 125–33. http://dx.doi.org/10.2166/wst.1994.0658.

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This paper is based on an extensive experimental investigation of bedload transport of noncohesive sediments at “limit deposition” in channels of circular and rectangular cross-section. The effect of permanent deposits on the invert of pipe channels on sediment carrying capacity and hydraulic resistance to flow is investigated. The sediment transport data from rectangular and pipe channels led to the development of empirical equations with high correlation coefficients. These equations showed the possibilities of their validity for either channel shape with the incorporation of appropriate shape parameters.

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25

Moutzouris, C. I. "LONGSHORE SEDIMENT TRANSPORT RATE vs. CROSS - SHORE DISTRIBUTION OF SEDIMENT GRAIN SIZES." Coastal Engineering Proceedings 1, no. 21 (January 29, 1988): 145. http://dx.doi.org/10.9753/icce.v21.145.

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Existing models for longshore sediment transport rate computations assume the sediment grain size and grain sizerelated parameters to be uniform in both the cross-shore and longshore directions. Field results from tideless beaches, which are briefly described in the paper, show that the latter change in both directions due to changing wave energylevels. The sensitivity analysis described in the paper shows that both longshore current and transport rate computations are sensitive to the cross-shore changes in grain size.Finally, a modified linearity coefficient for the wave power equation is proposed based upon the cross-shore distributions of grain size as found in nature.

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26

Krishnappan, Bommanna G. "Recent advances in basic and applied research in cohesive sediment transport in aquatic systems." Canadian Journal of Civil Engineering 34, no. 6 (June 1, 2007): 731–43. http://dx.doi.org/10.1139/l06-043.

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An overview of cohesive sediment transport processes is given in this paper, and a mass-balance equation that is commonly used to treat cohesive sediment transport is reviewed. The equation highlights transport parameters and processes that are important for modelling the transport of cohesive sediment. The flocculation mechanism that distinguishes cohesive sediment from its noncohesive counterpart is elaborated using a laboratory study that was carried out in a rotating circular flume using sediments from Hay River, Northwest Territories, Canada. A mathematical model of flocculation suitable for predicting flocculation of sediment in rotating circular flumes is reviewed. Other cohesive sediment transport processes such as erosion and deposition processes at the sediment-water interface, entrapment of fines in gravel beds, consolidation, fluid mud, and fluidization due to wave action are reviewed. Additional challenges and knowledge gaps that exist in the area of cohesive sediment transport are identified. Key words: cohesive sediment, flocculation, mathematical modelling of flocculation, rotating circular flume, erosion, deposition, fine sediment entrapment, fluid mud, consolidation, fluidization, waves.

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27

Henorman, Hanna Mariana, Duratul Ain Tholibon, Masyitah Md Nujid, Hamizah Mokhtar, Jamilah Rahim, and Azlinda Saadon. "The Functional Relationship of Sediment Transport under Various Simulated Rainfall Conditions." Fluids 7, no. 3 (March 15, 2022): 107. http://dx.doi.org/10.3390/fluids7030107.

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Sediment removed in the detachment process is transported by overland flow. Previous experimental and field works studied that sediment transport is influenced by hydraulic properties of flow, physical properties of soil, and surface characteristics. Several equations in predicting sediment transport have been developed from previous research. The objective of this paper was to establish the selected parameters that contribute to the sediment transport capacity in overland flow conditions under different rainfall pattern conditions and to evaluate their significance. The establishment of independent variables was performed using the dimensional analysis approach that is Buckingham’s π theorem. The final results obtained are a series of independent parameters; the Reynolds number (Re), dimensionless rainfall parameter iLν, hydraulic characteristics QLν that related to the dependent parameters; and dimensionless sediment transport qsρv. The relationship indicates that 63.6% to 72.44% of the variance in the independent parameters is in relation to the dependent parameter. From the iteration method, the estimation of constant and regression coefficient values is presented in the form of the general formula for linear and nonlinear model equations. The linear and nonlinear model equations have the highest model accuracy of 93.1% and 81.5%, respectively. However, the nonlinear model equation has the higher discrepancy ratio of 54.9%.

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28

Mailapalli, Damodhara R., Narendra S. Raghuwanshi, and Rajendra Singh. "Sediment Transport Model for a Surface Irrigation System." Applied and Environmental Soil Science 2013 (2013): 1–10. http://dx.doi.org/10.1155/2013/957956.

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Controlling irrigation-induced soil erosion is one of the important issues of irrigation management and surface water impairment. Irrigation models are useful in managing the irrigation and the associated ill effects on agricultural environment. In this paper, a physically based surface irrigation model was developed to predict sediment transport in irrigated furrows by integrating an irrigation hydraulic model with a quasi-steady state sediment transport model to predict sediment load in furrow irrigation. The irrigation hydraulic model simulates flow in a furrow irrigation system using the analytically solved zero-inertial overland flow equations and 1D-Green-Ampt, 2D-Fok, and Kostiakov-Lewis infiltration equations. Performance of the sediment transport model was evaluated for bare and cropped furrow fields. The results indicated that the sediment transport model can predict the initial sediment rate adequately, but the simulated sediment rate was less accurate for the later part of the irrigation event. Sensitivity analysis of the parameters of the sediment module showed that the soil erodibility coefficient was the most influential parameter for determining sediment load in furrow irrigation. The developed modeling tool can be used as a water management tool for mitigating sediment loss from the surface irrigated fields.

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29

Krupiński, Adam. "Analysis of sediment particle velocity in wave motion based on wave flume experiments." Studia Geotechnica et Mechanica 34, no. 2 (October 1, 2012): 41–50. http://dx.doi.org/10.2478/sgm021204.

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Abstract The experiment described was one of the elements of research into sediment transport conducted by the Division of Geotechnics of West-Pomeranian University of Technology. The experimental analyses were performed within the framework of the project “Building a knowledge transfer network on the directions and perspectives of developing wave laboratory and in situ research using innovative research equipment” launched by the Institute of Hydroengineering of the Polish Academy of Sciences in Gdańsk. The objective of the experiment was to determine relations between sediment transport and wave motion parameters and then use the obtained results to modify formulas defining sediment transport in rivers, like Ackers-White formula, by introducing basic parameters of wave motion as the force generating bed material transport. The article presents selected results of the experiment concerning sediment velocity field analysis conducted for different parameters of wave motion. The velocity vectors of particles suspended in water were measured with a Particle Image Velocimetry (PIV) apparatus registering suspended particles in a measurement flume by producing a series of laser pulses and analysing their displacement with a high-sensitivity camera connected to a computer. The article presents velocity fields of suspended bed material particles measured in the longitudinal section of the wave flume and their comparison with water velocity profiles calculated for the definite wave parameters. The results presented will be used in further research for relating parameters essential for the description of monochromatic wave motion to basic sediment transport parameters and „transforming” mean velocity and dynamic velocity in steady motion to mean wave front velocity and dynamic velocity in wave motion for a single wave.

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30

Hu, Peng, Liming Tan, Jiafeng Xie, and Zhiguo He. "TEST OF EMPIRICAL SEDIMENT TRANSPORT RELATIONS AGAINST EXPERIMENTAL SWASH DATA UNDER THE NON-CAPACITY MODELING FRAMEWORK." Coastal Engineering Proceedings, no. 36 (December 30, 2018): 81. http://dx.doi.org/10.9753/icce.v36.sediment.81.

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Swash sediment transport and beach deformation has received great attention in the past two decades. Quantification of swash-induced sediment transport rate is of vital importance for accurate prediction of beach deformation in the swash zone. Two empirical parameters are involved in this quantification, empirical relations for sediment transport capacity and the bed shear stress that may be used in the former. Since the swash zone is highly unsteady, of short cross-shore distance, sediment transport in this zone may be of high possibility to be lag of the flow variation. Thus we have firstly developed a non-capacity sediment transport model for the swash zone. This model appreciates the fact that the actual sediment transport rate may not be necessarily equal to the sediment transport capacity of the flow. In contrast to traditional capacity models that calculate sediment transport rate using directly empirical relations (Hu et al. 2015), the non-capacity model uses the advection-diffusion equation to calculate depth-averaged sediment concentration firstly, and afterwards compute sediment transport rate as flow depth*velocity*concentration. We have also noted that some empirical relations for sediment transport capacity may predict physically unrealistic high values of sediment concentration in the swash zone. This is attributed to the vanishing water depth in the swash zone, whereas existing empirical relations are developed for relatively large water depths (Hu et al. 2015; Li et al. 2017).

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31

Kuo, Ching-Ton, Ching-Her Hwang, and I.-Chou Tseng. "EXPERIMENTAL STUDY ON ON-OFFSHORE SEDIMENT TRANSPORT OF ACCRETIVE BEACH." Coastal Engineering Proceedings 1, no. 20 (January 29, 1986): 96. http://dx.doi.org/10.9753/icce.v20.96.

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In treating coastal proceses, sediment transport is usually divided into along-shore and on-offshore components. It is believed that the on-offshore component has a prominant connection with short-term profile changes, observed during storm wave climates. Obviously its shift of sand plays a very vital role in shoreline migration. In other words, the beach profile has great bearing on coastal phenomena related to on-offshore sediment transport. As we know, there have been many studies on this kind of sediment transport rate, and considerable amount of knowledge on this problem has been accumulated so far. Yet it seems that we are still far from a reliable formulus to estimate the beach profile changes. The reason why is due to the complexity of mechanics of sediment transport. Therefore, the aim of this study is to examine experimentally the mechanism between onoffshore sediment transport and the deformation processes of twodimensional beach profile. Then , a predictive model of the temporal and spatial distribution of net on-offshore sediment transport based on two-dimensional beach profiles and an equation of continuity of sediment transport is proposed. Various parameters of net on-offshore sediment transport in this model are discussed also.

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32

Willis, David H., and B. G. Krishnappan. "Numerical modelling of cohesive sediment transport in rivers." Canadian Journal of Civil Engineering 31, no. 5 (October 1, 2004): 749–58. http://dx.doi.org/10.1139/l04-043.

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Techniques available to practicing civil engineers for numerically modelling cohesive mud in rivers and estuaries are reviewed. Coupled models, treating water and sediment as a single process, remain research tools but are usually not three-dimensional. The decoupled approach, which separates water and sediment computations at each model time step, allows the three-dimensional representation of at least the bed and the use of well-proven, commercial, numerical, hydrodynamic models. Most hydrodynamic models compute sediment transport in suspension but may require modification of the dispersion coefficients to account for the presence of sediment. The sediment model deals with the sediment exchange between the water column and the bed using existing equations for erosion and deposition. Both equations relate the sediment exchange rates to the shear stress in the bottom boundary layer. In real rivers and estuaries, a depositional bed layer is associated with a period of low flow and shear, at slack tide for example, whereas in numerical models a layer is defined by the model time step. The sediment model keeps track of the uppermost layers at each model grid point, including consolidation and strengthening. Although numerical hydrodynamic models are based strongly on physics, sediment models are only numerical frameworks for interpolating and extrapolating full-scale field or laboratory measurements of "hydraulic sediment parameters," such as threshold shear stresses. Calibration and verification of models against measurement are therefore of prime importance.Key words: cohesive sediment, mathematical modelling, settling velocity, erosion, resuspension, deposition, fluid mud, bed layers.

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33

Nishi, Takahiro, Charles Lemckert, and Fumihiko YAMADA. "Eulerian-Lagrangian Measurements for Estimating the Sediment Transport Parameters in Estuary." PROCEEDINGS OF COASTAL ENGINEERING, JSCE 54 (2007): 1421–25. http://dx.doi.org/10.2208/proce1989.54.1421.

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34

Wu, Fu-Chun, and Hsieh Wen Shen. "First-order estimation of stochastic parameters of a sediment transport model." Journal of Hydraulic Research 37, no. 2 (March 1999): 213–27. http://dx.doi.org/10.1080/00221689909498307.

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35

Sharma, Anurag, Mahesh Patel, and Bimlesh Kumar. "Turbulent parameters and corresponding sediment transport in curved cross-section channel." ISH Journal of Hydraulic Engineering 21, no. 3 (April 7, 2015): 333–42. http://dx.doi.org/10.1080/09715010.2015.1029545.

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36

Verbanck, Michel A. "Assessment of sediment behaviour in a cunette-shaped sewer section." Water Science and Technology 33, no. 9 (April 1, 1996): 49–59. http://dx.doi.org/10.2166/wst.1996.0174.

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The accumulation of deposits in sewers causes widespread concerns of either operational or environmental nature. It is believed that a number of sediment-related nuisances can substantially be controlled in adapting the characteristics of sewer pipes as a function of local constraints and circumstances. In particular, key design parameters such as cross-section shape or hydraulic roughness of inner walls are currently selected basing more on empiricism and intuition than on full knowledge of the sediment transport driving processes. A valid track for optimization of these parameters is to run mathematical simulations of the sediment transport behaviour under varying design scenarios. This option, however, supposes that a robust mathematical procedure to compute sediment transport capacity in sewers is available, embracing all primary physical factors of influence. Starting from a theoretical description of shear turbulence suggested by Bagnold (1966), a suspension formula is developed dedicated to the specific sewer flow properties. Applying this formula to the case of a main sewer presenting a composite cross-section allows to illustrate how geometrical discontinuities influence sediment transport characteristics in real conduits.

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37

Zou, Xianjian, Chuanying Wang, Huan Song, Zengqiang Han, Zhimin Ma, and Weinbin Hu. "Applications of ultrasound imaging system for measuring water-sand parameters during sediment transport process in hydraulic model experiments." Journal of Hydroinformatics 20, no. 2 (December 4, 2017): 410–23. http://dx.doi.org/10.2166/hydro.2017.025.

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Abstract Moving particles and the topographic bed under muddy water or in sediment-laden flow are often clouded by suspended sediments, making it hard to detect or analyze for visualization. This paper concerns applications of ultrasound imaging measurement method for the visual measurement of related water-sand parameters during sediment transport process in hydraulic model experiments. We use a B-mode ultrasound imaging system to measure the related parameters of suspended sediment concentration (SSC), underwater topographic riverbed, flow velocity and sediment incipient motion, conducted at a water channel. A comprehensive measuring system for the visualization of multiple water-sand parameters is established. Results show that the measurement and analysis of SSC and its space distribution, topography bedform, flow velocity and flow field, and sediment incipient velocity can be realized. Ultrasound imaging measurements of SSC and their space distribution can be shown in real time, and also dynamic monitoring and analysis of sediment incipient motion and topography bedform during the sediment transport process. This method realizes the experimental visualization of the topographic bed and sediment-laden flow. Application of an ultrasound imaging measurement system has promoted the development of sediment movement law research and related hydraulic model experiment measurement technique.

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38

Chen, Yuechao, Makoto Nakatsugawa, and Hiroki Ohashi. "Research of Impacts of the 2018 Hokkaido Eastern Iburi Earthquake on Sediment Transport in the Atsuma River Basin Using the SWAT Model." Water 13, no. 3 (January 30, 2021): 356. http://dx.doi.org/10.3390/w13030356.

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Landslides, debris flows, and other secondary disasters caused by earthquakes threaten the safety and stability of river basins. Earthquakes occur frequently in Japan. Therefore, it is necessary to study the impact of earthquakes on sediment transport in river basins. In this study, considering the influence of reservoirs, the Soil and Water Assessment Tool-calibration and uncertainty program (SWAT-CUP) was employed to analyze the runoff parameter sensitivity and to optimize the parameters. We manually corrected the sediment transport parameters after earthquake, using the Soil and Water Assessment Tool (SWAT) model to assess the process of runoff and sediment transport in the Atsuma River basin before and after the 2018 Hokkaido Eastern Iburi Earthquake. The applicability of the SWAT model to runoff simulation in the Atsuma River basin and the changes of sediment transport process after the earthquake were studied. The research results show that the SWAT model can accurately simulate the runoff process in the Atsuma River basin, the Nash–Sutcliffe efficiency coefficient (NSE) is 0.61 in the calibration period, and is 0.74 in the verification period. The sediment transport increased greatly after the earthquake and it is roughly estimated that the amount of sediment transport per unit rainfall increased from 3.5 tons/mm/year before the earthquake to 6.2 tons/mm/year after the earthquake.

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Regueiro-Picallo, Manuel, Jose Anta, Joaquín Suárez, Jerónimo Puertas, Alfredo Jácome, and Juan Naves. "Characterisation of sediments during transport of solids in circular sewer pipes." Water Science and Technology 2017, no. 1 (March 7, 2018): 8–15. http://dx.doi.org/10.2166/wst.2018.055.

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Abstract This research is focused in the monitoring of sediments in circular sewer pipes with different diameters at a flume facility fed with urban wastewater. For this purpose, sediment physical and chemical characteristics, and sediment mobility were recorded. The Structure from Motion photogrammetric technique was used for the measurement of sediment bed evolution. In addition, sediment properties were determined in order to study the cohesiveness of the bed deposits. In particular, the chemical oxygen demand and the oxygen uptake rate of the sediment samples were analysed after different accumulation periods on the pipe inverts, resulting in a relation between these parameters and the mobility processes of solids.

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40

Schroeter, H. O., and W. E. Watt. "Practical simulation of sediment transport in urban runoff." Canadian Journal of Civil Engineering 16, no. 5 (October 1, 1989): 704–11. http://dx.doi.org/10.1139/l89-105.

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A model for simulating sediment transport in urban areas has been developed based on the concept of "equivalent solids reservoirs." The processes of erosion, deposition, and routing have been represented by simple algorithms, which are applied to typical urban drainage elements (surfaces, gutters, pipes, and detention ponds). Input requirements are limited and include two sediment characteristics (particle size and relative density), scour and deposition parameters, and initial sediment loadings. Hydraulic properties of the drainage elements and the inflow hydrograph to each element are also required. This sediment transport submodel is an integral part of Q'URM, the Queen's University Urban Runoff Model. It has been developed and calibrated on the basis of data from a stormwater quality sampling program on the Calvin Park basin in Kingston, Ontario, and verified on the basis of data from an independent study of runoff quality in the Malvern basin in Burlington, Ontario. Key words: urban hydrology, sediment transport, simulation, measurement.

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41

Geng, Yixin, Yujian Li, Liang Mao, and Peng An. "Parameter Calibration of Sediment Transport Capacity Formula of the Third Entrance of Xinqiman Reservoir in Tarim River Based on CCHE2D Model." Mathematical Problems in Engineering 2022 (August 2, 2022): 1–9. http://dx.doi.org/10.1155/2022/4227059.

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In this study, sediment transport at the third entrance of the Xinqiman Reservoir in the Tarim River was simulated using the CCHE2D model. The flow conditions, the suspended sediment concentration of each grain size, and the boundary grain size of the wash load in the reach were determined. Regressions between the suspended sediment concentration, S, and flow condition, U3/gH, and flow-sediment factor, U3/Rω, were developed, which strongly adhered to the power law and Zhang Ruijin’s formula for the sediment transport capacity. The parameters in Zhang Ruijin’s formula for the target reach were determined. Under the defined flow and sediment conditions, sediment particles ≥0.091 mm and particles ≤0.061 can be regarded as the bed material and wash loads, respectively. Using multivariate linear regression, the sediment transport capacity coefficient (k0) and exponent (m) were determined to be 0.0197 and 0.928, respectively. These results can serve as an important theoretical reference for the calculation of sediment transport at the third entrance of the Xinqiman Reservoir in the Tarim River.

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42

Bandeira, Jefferson V., and Lécio H. Salim. "Technetium-99m: From nuclear medicine applications to fine sediment transport studies." Nukleonika 62, no. 4 (December 1, 2017): 295–302. http://dx.doi.org/10.1515/nuka-2017-0043.

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Abstract The present work is a contribution to rescue the history of development of the application of 99mTc, widely used in nuclear medicine, to its use as tracer for the study of the transport of fine sediment in suspension, in water environment. It addresses the usefulness of its application in obtaining important parameters in environmental studies, illustrating them with some applications already performed and the results obtained. This kind of study, when associated with information on hydrodynamic parameters, for example, river, tidal, wind and wave currents, are powerful tools for the understanding and quantification of fine sediment transport in suspension. Fine sediment is an important vector in the transportation of heavy metals, organic matter and nutrients in water environment, and the quantitative knowledge of its behaviour is mandatory for studies of environmental impacts. Fine sediment labelled with 99mTc, can also be used to study the effect of human interventions, such as dredging of reservoirs, access channels and harbours, and the dumping of dredged materials in water bodies. Besides that, it can be used to optimize dredging works, evaluating the technical and economic feasibility of dumping sites and their environmental impact. It is a valuable support in the calibration and validation of mathematical models for sediment dynamics.

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43

Thomas, Severine, Peter V. Ridd, and Peter J. Smith. "New Instrumentation for Sediment Dynamics Studies." Marine Technology Society Journal 36, no. 1 (March 1, 2002): 55–58. http://dx.doi.org/10.4031/002533202787914278.

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The study of sediment transport processes is hampered by a lack of instrumentation for measuring important parameters such as erosion and deposition rates. This technical note describes three novel pieces of equipment that have been designed to provide information about erosion, deposition, suspended sediment concentration and light.

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44

Baniya, Mahendra B., Takashi Asaeda, Shivaram K.C., and Senavirathna M. D. H. Jayashanka. "Hydraulic Parameters for Sediment Transport and Prediction of Suspended Sediment for Kali Gandaki River Basin, Himalaya, Nepal." Water 11, no. 6 (June 12, 2019): 1229. http://dx.doi.org/10.3390/w11061229.

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Sediment yield is a complex phenomenon of weathering, land sliding, and glacial and fluvial erosion. It is highly dependent on the catchment area, topography, slope of the catchment terrain, rainfall, temperature, and soil characteristics. This study was designed to evaluate the key hydraulic parameters of sediment transport for Kali Gandaki River at Setibeni, Syangja, located about 5 km upstream from a hydropower dam. Key parameters, including the bed shear stress (τb), specific stream power (ω), and flow velocity (v) associated with the maximum boulder size transport, were determined throughout the years, 2003 to 2011, by using a derived lower boundary equation. Clockwise hysteresis loops of the average hysteresis index of +1.59 were developed and an average of 40.904 ± 12.453 Megatons (Mt) suspended sediment have been transported annually from the higher Himalayas to the hydropower reservoir. Artificial neural networks (ANNs) were used to predict the daily suspended sediment rate and annual sediment load as 35.190 ± 7.018 Mt, which was satisfactory compared to the multiple linear regression, nonlinear multiple regression, general power model, and log transform models, including the sediment rating curve. Performance indicators were used to compare these models and satisfactory fittings were observed in ANNs. The root mean square error (RMSE) of 1982 kg s−1, percent bias (PBIAS) of +14.26, RMSE-observations standard deviation ratio (RSR) of 0.55, coefficient of determination (R2) of 0.71, and Nash–Sutcliffe efficiency (NSE) of +0.70 revealed that the ANNs’ model performed satisfactorily among all the proposed models.

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45

Howell, Daniel, and Martin J. Siegert. "Intercomparison of subglacial sediment-deformation models: application to the Late Weichselian western Barents margin." Annals of Glaciology 30 (2000): 187–96. http://dx.doi.org/10.3189/172756400781820660.

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AbstractNumerical experiments, where a simple ice-sheet model was coupled with sediment-deformation models, were performed to investigate the transport of glacigenic material to the western Barents Shelf during the Late Weichselian. The ice-sheet model, and its environmental inputs, has been matched previously with a series of geological datasets relating to the maximum extent of the ice sheet (Howell and others, http://www.ggg.qub.ac.uk [rp05/1999]). Additional geological data on the volumes of sediment delivered to the Bear Island fan (Barents continental margin) are available for comparison. The experiments indicate the sensitivity of sediment transport and deposition to variations in (a) the ice-stream model and (b) a variety of model parameters. Two ice-stream models were used: (1) a height-above-buoyancy model, in which basal velocity is controlled by basal driving stress and a buoyancy-induced reduction in the normal load beneath a marine-based ice sheet; and (2) a modified version of the method presented by Alley (1990) in which basal velocity is related to pore-water pressure, sediment thickness, and driving basal stress. The results of the two different models were then compared. An extensive set of sensitivity tests was carried out to determine sediment-transport response to changes in the model’s parameters. Results indicate that, using physically realistic parameters for deforming subglacial sediment, both models reproduce the volume of Late Weichselian sediment measured on the Bear Island fan. Results from both models are sensitive to (1) cohesion of the sediment and (2) the thickness of deforming sediment beneath the ice sheet. The two models exhibited different degrees of sensitivity to the sediment parameters, with the height-above-buoyancy model proving to be less sensitive to variations in the thickness of the deforming sediment layer than the model proposed by Alley (1990). The differences between the two models examined here highlight the need for a comprehensive comparison of all the methodologies for calculating basal-ice motion currently in use.

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46

Brill, Dominik, Anna Pint, Kruawun Jankaew, Peter Frenzel, Klaus Schwarzer, Andreas Vött, and Helmut Brückner. "Sediment Transport and Hydrodynamic Parameters of Tsunami Waves Recorded in Onshore Geoarchives." Journal of Coastal Research 297 (September 2, 2014): 922–41. http://dx.doi.org/10.2112/jcoastres-d-13-00206.1.

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47

Le Roux, J. P. "A spreadsheet template for determining sediment transport vectors from grain-size parameters." Computers & Geosciences 20, no. 3 (April 1994): 433–40. http://dx.doi.org/10.1016/0098-3004(94)90051-5.

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48

Sadok, A., and C. Marche. "Une contribution pratique à l'estimation du transport des sédiments dans un écoulement fluvial." Canadian Journal of Civil Engineering 21, no. 3 (June 1, 1994): 490–98. http://dx.doi.org/10.1139/l94-052.

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Several computational methods of sediment discharge in open channel flows are reported in the existing literature. However, sediment transport is a complex procedure that implies several parameters which in some cases are difficult to estimate. Even if direct confrontations of methods used are published, it is difficult to draw significant conclusions that would help determine a model or the models likely to produce the best results for a specific case. To facilitate that choice, the authors have attempted to establish a classification of the various methods commonly used by determining their relative performance, and to improve the performance by proposing a new model which distinguishes the type of sediment transport and the nature of the bed. Key words: sediment discharge, sediment transport, open channel flow, model, performance.[Journal translation]

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49

Lamichhane, Suraj, and Nirajan Devkota. "Future Sediment Transport Ability and its Consequences in the Urbanized River Basin." Advances in Engineering and Technology: An International Journal 2, no. 01 (December 31, 2022): 11–24. http://dx.doi.org/10.3126/aet.v2i01.50432.

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The urbanization process of the Kathmandu Valley has a significant impact on LULC change, river runoff, and sediment transport capability. The historical sediment flow pattern indicates that the sediment transport capacity of the basin has increased even when precipitation and river discharge decreased. So, the sediment regression model is developed in this study in relation to discharge, precipitation, and built-up area change. Model parameters are calibrated and validated through the measured sediment discharge of the basin and the performance of the model is evaluated through NSE, PBIAS, and R2. In the future, the sediment transport capacity of the channel is projected for average monthly, maximum, and minimum flow conditions by +4.33%, +6%, and -2.66% respectively per decade due to the rise in the urban area (+6% per decade). Increasing the rigid ground surface through urbanization reduces the sediment generation through the watershed and balances the sediment transport capability, excess erosion is produced in the river channel causing a change in the river morphology. The findings of this study will be useful for planning and management of the river basin and the river structures.

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50

Mrokowska, Magdalena M., Paweł M. Rowiński, Leszek Książek, Andrzej Strużyński, Maciej Wyrębek, and Artur Radecki-Pawlik. "Laboratory studies on bedload transport under unsteady flow conditions." Journal of Hydrology and Hydromechanics 66, no. 1 (March 1, 2018): 23–31. http://dx.doi.org/10.1515/johh-2017-0032.

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Abstract Two sets of triangular hydrographs were generated in a 12-m-long laboratory flume for two sets of initial bed conditions: intact and water-worked gravel bed. Flowrate ranging from 0.0013 m3 s-1 to 0.0456 m3 s-1, water level ranging from 0.02 m to 0.11 m, and cumulative mass of transported sediment ranging from 4.5 kg to 14.2 kg were measured. Then, bedload transport rate, water surface slope, bed shear stress, and stream power were evaluated. The results indicated the impact of initial bed conditions and flow unsteadiness on bedload transport rate and total sediment yield. Difference in ratio between the amount of supplied sediment and total sediment yield for tests with different initial conditions was observed. Bedload rate, bed shear stress, and stream power demonstrated clock-wise hysteretic relation with flowrate. The study revealed practical aspects of experimental design, performance, and data analysis. Water surface slope evaluation based on spatial water depth data was discussed. It was shown that for certain conditions stream power was more adequate for the analysis of sediment transport dynamics than the bed shear stress. The relations between bedload transport dynamics, and flow and sediment parameters obtained by dimensional and multiple regression analysis were presented.

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