Anchor ice effects on river hydraulics

This paper describes a preliminary investigation that identified factors important in the prediction of river water quality, especially regarding dissolved oxygen (DO) concentration. Intermittent discharges from combined sewer overflows (CSOs) within the sewerage, and overflows at water reclamation works (WRW) cause dynamic conditions with respect to both river hydraulics and water quality. The impact of such discharges has been investigated under both wet and dry weather flow conditions. Data collected from the River Maun, UK, has shown that an immediate, transient oxygen demand exists downstream of an outfall during storm conditions. The presence of a delayed oxygen demand has also been identified. With regard to modelling, initial investigations used a simplified channel and the Streeter-Phelps (1925) dissolved oxygen sag curve equation. Later, a model taking into account hydrodynamic, transport and dispersion processes was used. This suggested that processes other than water phase degradation of organic matter significantly affect the dissolved oxygen concentration downstream of the location of an intermittent discharge. It is proposed that the dynamic rate of reaeration and the sediment oxygen demand should be the focus of further investigation.

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Modelling Weirs in Two-Dimensional Shallow Water Models

Water ◽

10.3390/w13162152 ◽

2021 ◽

Vol 13 (16) ◽

pp. 2152

Author(s):

Gonzalo García-Alén ◽

Olalla García-Fonte ◽

Luis Cea ◽

Luís Pena ◽

Jerónimo Puertas

Keyword(s):

Experimental Data ◽

Shallow Water ◽

Shallow Water Equations ◽

Water Model ◽

Two Dimensional ◽

Shallow Water Model ◽

Experimental Dataset ◽

River Hydraulics ◽

Shallow Water Models ◽

Water Models

2D models based on the shallow water equations are widely used in river hydraulics. However, these models can present deficiencies in those cases in which their intrinsic hypotheses are not fulfilled. One of these cases is in the presence of weirs. In this work we present an experimental dataset including 194 experiments in nine different weirs. The experimental data are compared to the numerical results obtained with a 2D shallow water model in order to quantify the discrepancies that exist due to the non-fulfillment of the hydrostatic pressure hypotheses. The experimental dataset presented can be used for the validation of other modelling approaches.

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River Hydraulics

10.1007/978-3-030-81768-8 ◽

2022 ◽

Keyword(s):

River Hydraulics

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Discussion on Anchor Ice

Transactions of the American Society of Civil Engineers ◽

10.1061/taceat.0000599 ◽

1887 ◽

Vol 16 (1) ◽

pp. 177-178

Author(s):

Charles B. Brush ◽

Benjamin S. Church ◽

Theodore Cooper

Keyword(s):

Anchor Ice

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Turbulence and Flow–Sediment Interactions in Open-Channel Flows

Water ◽

10.3390/w12113169 ◽

2020 ◽

Vol 12 (11) ◽

pp. 3169

Author(s):

Roberto Gaudio

Keyword(s):

Open Channel ◽

Field Experiments ◽

State Of The Art ◽

Channel Flows ◽

Special Issue ◽

Panoramic View ◽

Open Channel Flows ◽

River Hydraulics ◽

The World ◽

Computing Skills

The main focus of this Special Issue of Water is the state-of-the-art and recent research on turbulence and flow–sediment interactions in open-channel flows. Our knowledge of river hydraulics is becoming deeper and deeper, thanks to both laboratory/field experiments related to the characteristics of turbulence and their link to the erosion, transport, deposition, and local scouring phenomena. Collaboration among engineers, physicists, and other experts is increasing and furnishing new inter/multidisciplinary perspectives to the research in river hydraulics and fluid mechanics. At the same time, the development of both sophisticated laboratory instrumentation and computing skills is giving rise to excellent experimental–numerical comparative studies. Thus, this Special Issue, with ten papers by researchers from many institutions around the world, aims at offering a modern panoramic view on all the above aspects to the vast audience of river researchers.

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Towards a reasoned 1D river model calibration

Journal of Hydroinformatics ◽

10.2166/hydro.2005.0009 ◽

2005 ◽

Vol 7 (2) ◽

pp. 91-104 ◽

Cited By ~ 9

Author(s):

Jean-Philippe Vidal ◽

Sabine Moisan ◽

Jean-Baptiste Faure ◽

Denis Dartus

Keyword(s):

Model Calibration ◽

Expert Knowledge ◽

Fixed Bed ◽

Rainfall Runoff ◽

Simulation Code ◽

Hydraulic Simulation ◽

Flow Equations ◽

Knowledge Based ◽

River Hydraulics ◽

Knowledge Levels

Model calibration remains a critical step in numerical modelling. After many attempts to automate this task in water-related domains, questions about the actual need for calibrating physics-based models are still open. This paper proposes a framework for good model calibration practice for end-users of 1D hydraulic simulation codes. This framework includes a formalisation of objects used in 1D river hydraulics along with a generic conceptual description of the model calibration process. It was implemented within a knowledge-based system integrating a simulation code and expert knowledge about model calibration. A prototype calibration support system was then built up with a specific simulation code solving subcritical unsteady flow equations for fixed-bed rivers. The framework for model calibration is composed of three independent levels related, respectively, to the generic task, to the application domain and to the simulation code itself. The first two knowledge levels can thus easily be reused to build calibration support systems for other application domains, like 2D hydrodynamics or physics-based rainfall–runoff modelling.

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