Search results for "Channel geometry"

showing 5 items of 5 documents

Experimental observations of upstream overdeepening

2005

The issue of morphodynamic influence in meandering streams is investigated through a series of laboratory experiments on curved and straight flumes. Both qualitative and quantitative observations confirm the suitability of the recent theoretical developments (Zolezzi & Seminara 2001) that indicate the occurrence of two distinct regimes of morphodynamic influence, depending on the value of the width ratio of the channel β. The threshold value βR separating the upstream from the downstream influence regimes coincides with the resonant value discovered by Blondeaux & Seminara (1985). Indeed it is observed that upstream influence may occur only in relatively wide channels, while narrower stream…

BedformMechanics of MaterialsMechanical EngineeringOverdeepeningThe issue of morphodynamic influence in meandering streams is investigated through a series of laboratory experiments on curved and straight flumes. Both qualitative and quantitative observations confirm the suitability of the recent theoretical developments (Zolezzi & Seminara 2001) that indicate the occurrence of two distinct regimes of morphodynamic influence depending on the value of the width ratio of the channel β. The threshold value βR separating the upstream from the downstream influence regimes coincides with the resonant value discovered by Blondeaux & Seminara (1985). Indeed it is observed that upstream influence may occur only in relatively wide channels while narrower streams are dominated by downstream influence. A series of experiments has been carried out in order to check the above theoretical predictions and show for the first time evidence of the occurrence of upstream overdeepening. Two different sets of experiments have been designed where a discontinuity in channel geometry was present such that the channel morphodynamics was influenced in the upstream direction under super-resonant conditions (β >βR) and in the downstream direction under sub-resonant conditions (β <βR). Experimental results give qualitative and quantitative support to the theoretical predictions and allow us to clarify the limits of the linear analysis.MechanicsLinear analysisCondensed Matter PhysicsWidth ratioGeology
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Morphological Similarity of Channels: From Linear Erosional Features (Rill, Gully) to Alpine Rivers

2017

The geometric characteristics of incised features such as channels, rills, ephemeral gully, gully, represent the erosional transport regime and the fluvial dynamic equilibrium, and thus it is critical for the understanding of the long-term evolution of natural, agricultural, and anthropogenic landscapes. This paper examines the morphological similarity of channelized erosion in two different environments such as Alpine landscapes and cultivated hillslopes. The first dataset comprises six rivers in the Italian Alps, three in the Carnia region and three in the Dolomites, where erosion is mainly the effect of discharges with high sediment loads or landslides and debris flows. The agricultural …

Channelized erosion on hillslopeRiverchannelized erosion on hillslopes2300Erosion measurementChannel geometrySoil erosionEnvironmental ChemistrySoil ScienceDevelopment3304 Educationriverssoil erosion channel geometry channelized erosion on hillslopes rivers erosion measurement channelized erosion on hillslopes
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Influence of the channel design on the heat and mass exchange of induction channel furnace

2011

PurposeThe purpose of this paper is to present in‐depth numerical modelling of heat and mass exchange in industrial induction channel furnace (ICF).Design/methodology/approachThe turbulent heat and mass exchange in the melt is calculated using a three‐dimensional (3D) electromagnetic model and a 3D transient large eddy simulation method. The simulation model has been verified by flow velocity and temperature measurements, which were carried out using an industrial sized channel inductor operating with Wood's metal as a low temperature model melt.FindingsThe ICF is well‐established for melting, holding and casting in the metallurgical industry. But there are still open questions regarding th…

EngineeringElectromagnetic modelsLarge Eddy simulation methodsChannel geometryHeat and mass transferDewey Decimal Classification::600 | Technik::620 | Ingenieurwissenschaften und MaschinenbauMechanical engineeringInductorTemperature measurementModellingMetallurgical industryChannel designExperimentWood's metalMass transferLow temperaturesIndustryMass transferWood's metalElectrical and Electronic Engineeringddc:510Low frequency oscillationsMass exchangeTemperature measurementbusiness.industryApplied MathematicsThree dimensionalFurnaceMechanicsDesign/methodology/approachDewey Decimal Classification::500 | Naturwissenschaften::510 | MathematikComputer Science ApplicationsComputational Theory and MathematicsFlow velocityThree-dimensional (3D)Casting (metalworking)Numerical modellingMetallurgySimulation modelddc:620businessSimulationCommunication channelLarge eddy simulationNumerical analysis
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Morphological Similarity of Channels: From Linear Erosional Features (Rill, Gully) to Alpine Rivers

2017

Hydrologygeographygeography.geographical_feature_category010504 meteorology & atmospheric sciencesMorphological similarity0208 environmental biotechnologySoil Science02 engineering and technologyDevelopmentChannel geometry01 natural sciences020801 environmental engineeringRillEnvironmental ChemistryGeomorphologyGeology0105 earth and related environmental sciencesGeneral Environmental ScienceLand Degradation &amp; Development
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Ideal bulk pressure of active Brownian particles

2016

The extent to which active matter might be described by effective equilibrium concepts like temperature and pressure is currently being discussed intensely. Here, we study the simplest model, an ideal gas of noninteracting active Brownian particles. While the mechanical pressure exerted onto confining walls has been linked to correlations between particles' positions and their orientations, we show that these correlations are entirely controlled by boundary effects. We also consider a definition of local pressure, which describes interparticle forces in terms of momentum exchange between different regions of the system. We present three pieces of analytical evidence which indicate that such…

PhysicsIdeal (set theory)Statistical Mechanics (cond-mat.stat-mech)FOS: Physical sciences02 engineering and technologyCondensed Matter - Soft Condensed Matter021001 nanoscience & nanotechnologyChannel geometry01 natural sciencesVirial theoremIdeal gasActive matterMomentumClassical mechanics0103 physical sciencesSoft Condensed Matter (cond-mat.soft)Local pressure010306 general physics0210 nano-technologyBrownian motionCondensed Matter - Statistical Mechanics
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