• Title/Summary/Keyword: suspended load

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Upwind Finite Element Model for Suspended Sediment Transport

  • Noh, Joon-Woo
    • Journal of Wetlands Research
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    • v.5 no.1
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    • pp.67-78
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    • 2003
  • The unsteady 2D convection and diffusion equation is solved numerically for the real-time simulation of suspended load propagation. The streamlined upwind scheme efficiently reduces numerical oscillations due to the high Peclet number in the convection dominant flow. By using the mixed boundary condition to express the external source terms or externally induced suspended load as a function of time in the algorithm, the model is capable of handling not only continuous load cases but also non-continuous suspended load influx. The suspended load transport modelwas verified using a case study for which an analytical exact solution is available and was applied to the real-time simulation of a suspended load influx case on the Mississippi River. The model algorithm can provide a framework upon which water quality as well as contaminant transport models can be built.

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A Study on Sediment Load in the Milyang River (유사량 산정에 관한 연구 (밀양강을 중심으로))

  • 안세영;민벙형
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.22 no.4
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    • pp.96-107
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    • 1980
  • This study is carried out to estimate the rate of sediment transportation both to measure the amount of suspended and bedload sediment that moves on or near the river bed and passes through the cross section of a river in unit time, with suspended and bed load samplers used for the Milyang river and to determine the most satisfactory and convenient formula of some formulas for sediment discharge by comparing the measured rate with the calculated rate. The results of this study are summarized as follows; 1) The interrelationship (1) between the total discharge and the total sediment discharge (2) between discharge and suspended sediment load and (3) between discharge and bed load in the Milyang river are (1) i) 4$\leq$Q$\leq$100 C.M.S. Qr=0. 00272 Q0.70 (kg/sec) ii) 150$\leq$Q$\leq$800 C.M.S. Qr=0. 4807 Q0.46 (kg/sec) (2) Qs~=0. 07576 Q1.02 (kg/sec) (3) QB=0. 00957 Q0.44 (kg/sec) 2) The rate of suspended sediment load to total sediment discharge is found to be about; 99%. The suspended load is shown to be almost wash load which consists of silt and clay. 3) The relation between the total discharge and the suspended sediment load that are measured at three medium and small rivers in Korea is Qs=0. 13831 Q0.97 (kg/sec) 4) Brown's formula is determined to be the most convenient formula for application and comparison with observed data obtained for the Milyang river.

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Analysis of Suspended Load using A Two-Dimensional Advection-Diffusion Equation in Coastal Zone (2차원 이송-확산 방정식을 이용한 해안에서의 부유사 해석)

  • Kang, Gyu-Young;Kim, Su-Jin;Cho, Yong-Sik
    • 한국방재학회:학술대회논문집
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    • 2007.02a
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    • pp.177-180
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    • 2007
  • Numerical simulations on the suspended load in the Do jang fish port are carried out. Suspended load is analysed by using the two-dimensional advection-diffusion equation. To describe behaviors of a pollutant in costal zone, a split-operator method is applied to the numerical model. The advection part is first solved by SOWMAC and then the diffusion part is solved by a three-level locally implicit scheme.

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Prediction of total sediment load: A case study of Wadi Arbaat in eastern Sudan

  • Aldrees, Ali;Bakheit, Abubakr Taha;Assilzadeh, Hamid
    • Smart Structures and Systems
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    • v.26 no.6
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    • pp.781-796
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    • 2020
  • Prediction of total sediment load is essential in an extensive range of problems such as the design of the dead volume of dams, design of stable channels, sediment transport in the rivers, calculation of bridge piers degradation, prediction of sand and gravel mining effects on river-bed equilibrium, determination of the environmental impacts and dredging necessities. This paper is aimed to investigate and predict the total sediment load of the Wadi Arbaat in Eastern Sudan. The study was estimated the sediment load by separate total sediment load into bedload and Suspended Load (SL), independently. Although the sediment records are not sufficient to construct the discharge-sediment yield relationship and Sediment Rating Curve (SRC), the total sediment loads were predicted based on the discharge and Suspended Sediment Concentration (SSC). The turbidity data NTU in water quality has been used for prediction of the SSC in the estimation of suspended Sediment Yield (SY) transport of Wadi Arbaat. The sediment curves can be used for the estimation of the suspended SYs from the watershed area. The amount of information available for Khor Arbaat case study on sediment is poor data. However, the total sediment load is essential for the optimal control of the sediment transport on Khor Arbaat sediment and the protection of the dams on the upper gate area. The results show that the proposed model is found to be considered adequate to predict the total sediment load.

Device Development for Measurement of Bed Load and Suspended Particle Movement in Coastal Water and its Application to Field (연안의 부유물 이동 측정 장치 개발과 현장 적용)

  • Lee, Chung Il
    • Journal of Environmental Science International
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    • v.23 no.2
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    • pp.323-330
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    • 2014
  • Transport of bed load and suspended particle in coastal waters is main factor causing change in shoreline, and effective measurement method and appropriate equipment is required. To measure bed load and suspended particle transport an equipment was designed and manufactured, and it was applied in the field. The equipment consists of four main elements, body supporter, bed load and suspended particle sampler, sampler support and lock. Eight samplers were installed along the circumference of each supporter, and each sample is a 45-degree intervals. The field experiment was done once along Gyeongpo beach in August 2013. This note described the design and function of the equipment and results of field experiments.

Improvement of Einstein's Suspended Load Equation (Einstein 부유사량 산정식의 개선)

  • Yu, Dong-Hun;Sin, Seung-Ho;Im, Hak-Su
    • Journal of Korea Water Resources Association
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    • v.33 no.6
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    • pp.815-825
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    • 2000
  • In the present work Einstein's(l942) suspended load equation IS refined in vanous aspects. After checking the flow characteristics a new method is presented for the estimation of zero velocity point at the condition of smooth turbulent flow, and non-dimensional number of suspended load is introduced for the clear representation of suspended load equation. And a recent equation of bed load is employed in order to calculate accurately the sediment concentration at a reference point. Several approximation equations are also developed to compute directly or explicitly two integrals introduced in the equations. The refined equation has been tested against the measurement data collected by Brownlie(l981) in comparison with Einstein's original equation.uation.

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Comparison of Characteristics of Suspended Matters in Streams by Dry/Rainy season and Watershed Characteristics (비강우/강우기와 유역특성에 따른 하천의 부유물질 성상별 유출 특성 비교)

  • Park, Jihyoung;Sohn, Sumin
    • Journal of Korean Society on Water Environment
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    • v.29 no.6
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    • pp.739-745
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    • 2013
  • This paper investigated the runoff characteristics of different properties of suspended solids in streams according to the watershed characteristics and dry/rainy season. Suspended solids were divided into VSS and NVSS depending on volatilization. The main results of this study were as follows. TSS were more correlated with NVSS than VSS. Suspended solids were positively related with the proportion of urban > paddy > upland, negatively related with forest cover. VSS were positively correlated with POP and POC. VSS, measured in dry season, would partly result from autochthonous production and could be an indirect indicator of organic suspended solids.

Non-linear time-dependent post-elastic analysis of suspended cable considering creep effect

  • Kmet, S.;Tomko, M.;Brda, J.
    • Structural Engineering and Mechanics
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    • v.22 no.2
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    • pp.197-222
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    • 2006
  • In this paper, the non-linear time-dependent closed-form, discrete and combined solutions for the post-elastic response of a geometrically and physically non-linear suspended cable to a uniformly distributed load considering the creep effects, are presented. The time-dependent closed-form method for the particularly straightforward determination of a vertical uniformly distributed load applied over the entire span of a cable and the accompanying deflection at time t corresponding to the elastic limit and/or to the elastic region, post-elastic and failure range of a suspended cable is described. The actual stress-strain properties of steel cables as well as creep of cables and their rheological characteristics are considered. In this solution, applying the Irvine's theory, the direct use of experimental data, such as the actual stress-strain and strain-time properties of high-strength steel cables, is implemented. The results obtained by the closed-form solution, i.e., a load corresponding to the elastic limit, post-elastic and failure range at time t, enable the direct use in the discrete non-linear time-dependent post-elastic analysis of a suspended cable. This initial value of load is necessary for the non-linear time-dependent elastic and post-elastic discrete analysis, concerning incremental and iterative solution strategies with tangent modulus concept. At each time step, the suspended cable is analyzed under the applied load and imposed deformations originated due to creep. This combined time-dependent approach, based on the closed-form solution and on the FEM, allows a prediction of the required load that occurs in the post-elastic region. The application of the described methods and derived equations is illustrated by numerical examples.

Physiological Characteristics of Olive Flounder (Paralichthys olivaceus) and Korean Rockfish (Sebastes schlegelii) According to the Concentration of Suspended Load (부유사 농도에 따른 넙치와 조피볼락의 생리학적 특성)

  • Ha-Jeong Son;Kwang-Min Choi;Gyoungsik Kang;Won-Sik Woo;Kyung-Ho Kim;Min Yong Sohn;Min-Soo Joo;Chan-Il Park
    • Korean Journal of Ichthyology
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    • v.34 no.4
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    • pp.253-261
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    • 2022
  • After exposing Olive flounder and Korean rockfish to the concentration ranges of control (0 mg/L), 100 mg/L, 250 mg/L, 500 mg/L, and 1,000 mg/L, to investigate the physiological properties of suspended load on fish AST/GOT, ALT/GPT, ALP and cortisol were analyzed. As a result of the analysis, the AST/GOT, ALT/GPT, ALP and cortisol values were higher in the suspended load concentration section than in the control group. After artificial infection with S. parauberis for Olive flounder and V. harveyi for Korean rockfish exposed to suspended load, the survival rate was higher in the control group than in the suspended load concentration section. These results are related to the previously study results of suspended load that adversely affect fish, suggesting that suspended load affects the health of fish.

Effect of the Forest Road on Suspended Sediment Yield in the Small Forest Watershed (산지(山地) 소유역(小流域)에 개설(開設)된 임도(林道)가 부유사(浮遊砂) 유출(流出)에 미치는 영향(影響))

  • Oh, Jae-Man;Inoue, Shoji;Ezaki, Tsugio;Chun, Kun-Woo
    • Journal of Korean Society of Forest Science
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    • v.88 no.4
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    • pp.477-484
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    • 1999
  • This study was conducted to investigate the effect of forest road on the suspended sediment yield into a stream in the small forest watershed. The samples of suspended sediment yield were collected at surveying points A and B in mountains watersheds unaffected by forest road, and at surveying point C affected by forest road. When hourly change of suspended sediment concentration was investigated, it showed the highest increase along the forest road, and the peak of suspended sediment concentration due to the watershed characteristics of each surveying point occurred before or at the same time with, the peak of discharge. This may be due to the time lag in which stagnated unstable suspended sediment moved strongly upon rainfall. Although suspended sediment load varied depending upon rainfall factors and surveying period, suspended sediment load per unit watershed flowed out 4.1 times more at the point C than at the point A and B. The suspended sediment load on 18~19 September, 1998, strongly affected by rainfall factors, was 4.179g/sec/㏊ at the point C, and 0.343g/sec/㏊ and 0.147g/sec/㏊ at the point A and B, respectively. This load was 12 times higher at the point C than at the point A and 28 times higher than at the point B.

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