Morphodynamics of ecological scours as deep pool habitats

Journal of Ecohydraulics, Journal Year: 2025, Volume and Issue: unknown, P. 1 - 22

Published: Jan. 24, 2025

Language: Английский

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Assessing the backwater rise of floating barriers with racks for various blockages in open channels

Journal of Engineering and Applied Science, Journal Year: 2025, Volume and Issue: 72(1)

Published: Feb. 7, 2025

Abstract One major risk in the stream is thought to be debris. The general effects of debris spreading have a detrimental effect on water infrastructure and activities. A rack (curtain) with float units top component floating barrier that used Egypt trap It installed upstream structures collect protect such from clogging. Units steel racks do not extend or rest level channel bed. majority earlier researches examined hydraulics trash racks; however, there lack knowledge involving hydraulic performance barriers blocking. hundred experiments were conducted study open channels, regarding discharges, flow depths, blockage ratios which was defined as blocked area relative projected rack. findings show backwater rise (Δ h ) increased through increasing Froude numbers ratio. Whilst, depth caused decrease Δ at constant ratio new equation developed tested parameters predict for range 0.013 ≤ F o 0.077, 0.25 B r 1, 0.063 c 0.40. values limits conditions considered minor terms practical applicability, 100 mm prototype. Consequently, this type optimal choice trapping before reaching body structure, serving primary line defense.

Language: Английский

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Stability of an Idealized Floating Carpet of Plastic Spheres in an Open Channel Flow

Journal of Hydraulic Engineering, Journal Year: 2025, Volume and Issue: 151(4)

Published: March 24, 2025

Language: Английский

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Investigation of hydrodynamic characteristics with three types of vegetation accumulation at trash racks

Journal of Hydrodynamics, Journal Year: 2025, Volume and Issue: unknown

Published: March 20, 2025

Language: Английский

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Open check dams and large wood: head losses and release conditions

Natural hazards and earth system sciences, Journal Year: 2020, Volume and Issue: 20(12), P. 3293 - 3314

Published: Dec. 4, 2020

Abstract. Open check dams are strategic structures to control sediment and large-wood transport during extreme flood events in steep streams piedmont rivers. Large wood (LW) tends accumulate at such structures, obstruct their openings increase energy head losses, thus increasing flow levels. The extent variability which the stage–discharge relationship of a dam is modified by LW presence has so far not been clear. In addition, sufficiently high flows may trigger sudden release trapped with eventual dramatic consequences downstream. This paper provides experimental quantification LW-related loss simple ways compute related water depth various shapes: trapezoidal, slit, slot sabo (i.e. made piles), consideration capacity through open bodies atop spillways. it was observed that often released over structure when overflowing depth, i.e. total minus spillway elevation, about 3–5 times mean log diameter. Two regimes accumulations were observed. Dams low permeability generate velocity upstream, then accumulates as floating carpets, single layer. Conversely, maintain velocities immediately upstream dense complex 3D patterns. because drag forces stronger than buoyancy, allowing logs be sucked below surface. cases, releases occur for higher losses higher. A new dimensionless number, namely buoyancy-to-drag-force ratio, can used whether (or not) stay floating-carpet domain where buoyancy prevails force.

Language: Английский

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Laboratory study on the characteristics of large wood and debris flow processes at slit-check dams

Landslides, Journal Year: 2020, Volume and Issue: 17(7), P. 1703 - 1711

Published: May 9, 2020

Language: Английский

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Regulation effect of slit-check dam against woody debris flow: Laboratory test

Frontiers in Earth Science, Journal Year: 2023, Volume and Issue: 10

Published: Jan. 5, 2023

Woody debris flows (i.e., carrying wood) are common in mountainous and forested areas. They can cause more severe hazards due to the effects of LW (woody larger than 1 m length 10 cm width) compared without LW. Mitigation structures for have considered little regulating effect on influence regulation sediment. Thus, model tests were conducted discuss slit-check dams woody flow. Research results demonstrated that effectively regulate overflows. Once overflow occurs, sediment trapping efficiency wood retention rate dramatically decrease. The shared a linear relationship with relative opening width, height-to-width ratio opening, density . However, this was also influenced by A logarithmic between obtained. is mainly determined channel width dam. Three draining patterns at dam three clogging types openings observed. Some design criteria structure parameters proposed. These research promote better understanding provide basis optimal dams.

Language: Английский

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Effects of large wood (LW) blockage on bedload connectivity in the presence of a hydraulic structure

Ecological Engineering, Journal Year: 2021, Volume and Issue: 161, P. 106156 - 106156

Published: Jan. 25, 2021

Language: Английский

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Physical modelling of large wood (LW) processes relevant for river management: Perspectives from New Zealand and Switzerland

Earth Surface Processes and Landforms, Journal Year: 2021, Volume and Issue: 47(1), P. 32 - 57

Published: June 30, 2021

Abstract In the last 30 years, work on large wood (LW) has expanded and matured considerably, river scientists, managers practitioners now have a better appreciation of role LW in maintaining ecosystems, forming or stabilizing riverine landforms, interacting with morphodynamics. We gained understanding hazards posed by recruitment transport channel associated infrastructure. While dynamics traditionally been studied natural environment, innovations laboratory techniques enabled important advances process dynamics, using physical scale models, new sensors, scanners sophisticated model boundary conditions. Current trends research focus (1) mobilization logs, (2) trapping deposition sediment presence (3) contribution to hydraulic flow resistance. Ultimately, combined is needed assess impacts upon infrastructure erodible boundaries, such as bridge piers retention racks. this review, we present critical analysis emerging experimental obtained through modelling studies. put recent context global management challenges. particular, set our environmental engineering issues that confront catchment resource Switzerland New Zealand. show how improved models incorporating transport, accumulation scouring processes are contribute more reliable hazard risk assessment LW‐prone systems.

Language: Английский

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Influence of velocity field on driftwood accumulation at a bridge with a single pier

Environmental Fluid Mechanics, Journal Year: 2021, Volume and Issue: 21(3), P. 693 - 711

Published: May 3, 2021

Language: Английский

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