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Hybrid Modelling Using Lattice Boltzmann and Finite Difference Methods of Dikes Effect on Sediment Transport and Morphological Processes with a Quasi-Tridimensional Approach

Machrouhi Khalil, Bendaraa Anass, Charafi My Mustapha, Hasnaoui Abdellatif

Ecological Engineering & Environmental Technology

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2024

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Vol. 25, iss. 11

146--162

EN

This paper presents the development of a quasi-three-dimensional model that utilizes an equilibrium technique to investigate the morphological change of a channel focused on transport of sediment. The authors developed a computational algorithm that integrates two numerical techniques, specifically the Lattice Boltzmann Method (LBM) and the finite-difference method (FDM), to perform a hybrid calculation. The aforementioned algorithm was employed to investigate the impact of dykes on the dynamics of channel flow, sediment transport, and bed evolution. To derive the three-dimensional velocity field, the Boltzmann lattice method is employed to compute the two horizontal components of the vertically integrated velocity. Subsequently, these two components are combined with a logarithmic vertical profile. The process of sediment particle transport can be divided into two components: the bed load transport rate and the suspended load transport rate. The latter determination is achieved through the computation of the equilibrium flow rate of suspended sediment, which is derived from the equilibrium concentrations and logarithmic velocities. by comparing its outputs to previous research on constant width channels and horizontal beds, especially in dykes, the model was validated. This model accurately predicts sediment transport as bed load and suspended load, which is important for understanding sediment dynamics around such structures. the model’s ability to anticipate sediment erosion and deposition across the channel, providing crucial insights into river detours and other sedimentary processes.

2

Morphological analysis of the Woji River in Port Harcourt, Nigeria : using temporal data and mathematical algorithm

Anya M. U. K., Ezekwe C. I., Oyegun C. U.

Landform Analysis

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2017

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Vol. 35

45--54

EN

The research analysed morphological variations of the Woji River between 1986 and 2016 using mathematical extrapolations and temporal data. A 50% reduction in the River mean channel width, full-bank discharge and the stream power was found. Channel siltation occurred due to high sediment fluxes from rapid urban processes versus reduced stream power of the river. Water hyacinth invasion, domestic waste dumps and narrow culvers constricted the river channels. Finally, an impaired river status was found and extinction projected by 2043. Recommended were correction and monitoring exercises to check activities along the river channel and to restore the head stream wetlands.

3

Issues of channel processes research for the waterways maintenance at unconfined river channels in Russia

Chalov Roman S.

Geography and Tourism

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2016

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Vol. 4, No. 2

23--25

EN

The article uses the example of the selected reaches of the main Russian rivers to discuss river transport capacity and difficulties in the maintenance of waterways in Russia that arise from the dynamics of fluvial processes. Attention is drawn to changeable river conditions resulting from both natural factors and the presence of hydrotechnical structures. An attempt is made to indicate “natural” river reaches and the ones transformed as a result of damming, which include the accumulation and erosion zones (above and below a dam). It is emphasized that the issues related to the use of waterways are affected by changeable hydroclimatic conditions and the occurrence of ice phenomena.

4

Changes of the morphology of the Ropa river — upstream and downstream of the Klimkówka water reservoir

Wiejaczka Ł., Kiszka K., Bochenek W.

Studia Geomorphologica Carpatho-Balcanica

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2014

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Vol. 48

61--76

EN

The paper outlines changes in the channel morphology of the Ropa riverbed over the last six years, taking into account the role of large floods and the Klimkówka water reservoir in shaping the morphology of the riverbed. The analysis was based on annual geodetic measurements of the Ropa riverbed conducted between 2009–2014. The research was carried out in four cross profiles of the riverbed located upstream (1 profile) and downstream (3 profiles) of the reservoir. In order to recognise the direction and scale of morphology changes of the riverbed, additional analyses of water levels in the Ropa River was performed in the analysed multiannual period. The conducted analysis led to the conclusion that floods with extremely large discharges are the key factor causing the deepening of the riverbed downstream from the reservoir. It can be up to about 70 cm deep during a single event. The reservoir is just one additional factor of many which shape the direction and scale of changes to the riverbed. A significant role in modifying the riverbed morphology upstream from the reservoir is played by river control works, which diminish the effects of sediment accumulation occurring on this section.

5

Ocena tendencji współczesnej ewolucji wybranego fragmentu koryta dolnego Bugu na podstawie materiałów kartograficznych i teledetekcyjnych

Ostrowski P, Kaszyński K.

Landform Analysis

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2014

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Vol. 26

11--20

PL

W artykule przedstawiono ocenę tendencji zmian morfologii strefy korytowej Bugu na odcinku między 12. a 22. km rzeki (Dolina Dolnego Bugu). Analizę wykonano w środowisku GIS na podstawie porównania materiałów kartograficznych i teledetekcyjnych z okresu od 1891 do 2013 r. Poprzez morfologię strefy korytowej rozumiano przebieg koryta (jego układ w planie) oraz układ wypełnionych wodą form – głównie zanikających koryt bocznych, rynien erozyjnych przepływów wezbraniowych oraz starorzeczy w proksymalnej części równi zalewowej.

EN

Paper contains an analysis of trends in morphology changes through the Bug section between 12 and 22 km of its course (within the valley of the lower Bug). Performed in GIS environment analysis was based on maps and remote sensing materials that cover the period of time from 1891 to 2013. The channel morphology is defined here as the channel course (its planform) with a system of filled with water depressions (side arms, erosional pathways of overbank flow and oxbow lakes) located in proximal floodplain.

6

Wpływ zjawisk lodowych na erozję brzegów koryta rzecznego na przykładzie rzeki Łyny

Kalinowski A., Glińska-Lewczuk K, Burandt P, Banaszek Ż

Inżynieria Ekologiczna

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2012

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Nr 31

57--71

PL

W artykule podjęto próbę analizy wpływu zjawisk lodowych na erozję brzegów koryta rzeki pojeziernej na przykładzie rzeki Łyny (północno-wschodnia Polska). Do analizy wytypowano przekrój Smolajny, położony w jej środkowym biegu. Badania przeprowadzono w latach hydrologicznych 2005-2012. W badanym okresie obserwowano występowanie, rozwój i intensywność zjawisk lodowych, takich jak: lód brzegowy, pokrywa lodowa, spływ wody na lodzie na tle zmian cech morfologicznych koryta rzecznego. W wyniku obserwacji stwierdzono skokowe zwiększenie się szerokości koryta w badanym profilu poprzecznym (dwukrotnie po 0,5 m). Związane było to z długim czasem zalegania grubej pokrywy lodowej. W latach 2005-2012 zaobserwowano fluktuacje wielkości cech morfometrycznych, zarówno dodatnie jak i ujemne. Czynnikiem kształtującym brzegi koryta są ponadto gwałtowne roztopy pokrywy śnieżnej przy jednoczesnym utrzymywaniu się pokrywy lodowej. Wpływa to na zwiększone podmywanie brzegów koryta. Wykazano, że w badanym okresie nastąpiło zwiększenie szerokości koryta w badanym przekroju o jeden metr, zwiększenie powierzchni przekroju poprzecznego oraz głębokości maksymalnej i średniej.

EN

The aim of the paper is attempt to analysis influence on bank erosion on example Łyna river (NE Poland). The analysis has been performed at the cross section of Smolajny during hydrological years 2005-2012. In that period we observed occurrence, evolution and intensity of ice phenomena, such as: border ice, ice cover, water runoff on ice cover. Simultaneously, hydrological and morphological measurements of bed channel have been done. Results showed that width of river bed had increase, bit by bit (twice by 0,5 m), in observed cross section. There was observed fluctuation attributes of morphology in years 2005-2012, both positive and negative. Sudden snowmelt has a great impact on bank erosion, with prolonged ice cover. That situation has influence on sapping of banks. It was stated that, in spite of fluctuations of channel morphological parameters, the overall increase in the channel width was at about 1m in 2005-2012. Similarly other parameters, as wetted area, maximal and average depths have increased in those years.

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Wpływ podłoża aluwiów na morfologię koryta Wisły w rejonie Góry Kalwarii

Falkowski T., Złotoszewska-Niedziałek H.

Przegląd Naukowy Inżynieria i Kształtowanie Środowiska

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2003

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Vol. 12, No. 2

75--81

EN

The investigations, carried out in the Vistula river valley near Góra Kalwaria (Vistula middle course) were focused on the estimation of connections between alluvial basement position and contemporary channel stability. The culmination of basement was discovered in the upper part of the studied reach. It is generally composed of fluvioglacial deposits, covered by coarse-grained residuum residual lag. The occurence of this culmination has an effect on the position of the main channel during high water states, as well as lateral erosion and stability of channel depositional forms.