Vertical sorting in intense transport of bimodal contact load: measured distributions in collisional layer and effects on bed friction and flow condition

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68407700%3A21110%2F25%3A00385643" target="_blank" >RIV/68407700:21110/25:00385643 - isvavai.cz</a>

Výsledek na webu

<a href="http://dx.doi.org/10.64697/978-90-835589-7-4_41WC-P1990-cd" target="_blank" >http://dx.doi.org/10.64697/978-90-835589-7-4_41WC-P1990-cd</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.64697/978-90-835589-7-4_41WC-P1990-cd" target="_blank" >10.64697/978-90-835589-7-4_41WC-P1990-cd</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Vertical sorting in intense transport of bimodal contact load: measured distributions in collisional layer and effects on bed friction and flow condition

Popis výsledku v původním jazyce

In the intense transport of bimodal contact load under high bed shear conditions, particles of the two fractions, which differ in size, tend to separate. The finer particles form an interfacial layer at the top of the mobile bed, while the coarser particles predominantly occupy the collisional layer above the interface. We report on tilting-flume experiments focusing on measurements of the local velocity and concentration distributions of particles for each fraction within the collisional layer. The results reveal that, due to vertical sorting, the presence of finer fraction particles rapidly diminishes with increasing elevation above the interfacial layer, whereas the local concentration of the coarser fraction is higher within the collisional layer and reaches a maximum near the center of the layer. The local velocity of the sediment is lower than the local velocity of water at the same elevations, indicating the expected local slip between the phases within the collisional layer. Furthermore, we utilize the measured integral quantities along with a previously collected dataset to compare similar flows with unimodal and bimodal transport. The comparison indicates that bimodal transport offers advantages in terms of reduced channel resistance and enhanced transport capacity.

Název v anglickém jazyce

Vertical sorting in intense transport of bimodal contact load: measured distributions in collisional layer and effects on bed friction and flow condition

Popis výsledku anglicky

In the intense transport of bimodal contact load under high bed shear conditions, particles of the two fractions, which differ in size, tend to separate. The finer particles form an interfacial layer at the top of the mobile bed, while the coarser particles predominantly occupy the collisional layer above the interface. We report on tilting-flume experiments focusing on measurements of the local velocity and concentration distributions of particles for each fraction within the collisional layer. The results reveal that, due to vertical sorting, the presence of finer fraction particles rapidly diminishes with increasing elevation above the interfacial layer, whereas the local concentration of the coarser fraction is higher within the collisional layer and reaches a maximum near the center of the layer. The local velocity of the sediment is lower than the local velocity of water at the same elevations, indicating the expected local slip between the phases within the collisional layer. Furthermore, we utilize the measured integral quantities along with a previously collected dataset to compare similar flows with unimodal and bimodal transport. The comparison indicates that bimodal transport offers advantages in terms of reduced channel resistance and enhanced transport capacity.

Druh

D - Stať ve sborníku

CEP obor

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OECD FORD obor

20101 - Civil engineering

Projekt

<a href="/cs/project/GA23-07772S" target="_blank" >GA23-07772S: Struktura a pohyb dnových splavenin nad erodovaným rovným dnem v korytě: vliv různozrnnosti</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2025

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název statě ve sborníku

Proceedings of the 41st IAHR World Congress

ISBN

978-90-835589-7-4

ISSN

2521-7119

e-ISSN

2521-7119

Počet stran výsledku

7

Strana od-do

671-677

Název nakladatele

IAHR - International Association for Hydro-Environment Engineering and Research

Místo vydání

Madrid

Místo konání akce

Singapore

Datum konání akce

22. 6. 2025

Typ akce podle státní příslušnosti

WRD - Celosvětová akce

Kód UT WoS článku

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