Next Article in Journal
Simulated Flow Velocity Structure in Meandering Channels: Stratification and Inertia Effects Caused by Suspended Sediment
Next Article in Special Issue
Water-Worked Bedload: Hydrodynamics and Mass Transport
Previous Article in Journal
Changes in Vegetation and Geomorphological Condition 10 Years after Riparian Restoration
Previous Article in Special Issue
The Logarithmic Law of the Wall in Flows over Mobile Lattice-Arranged Granular Beds
Open AccessArticle

Roughness Effect of Submerged Groyne Fields with Varying Length, Groyne Distance, and Groyne Types

1
Aller-Ohre-Verband, 38518 Gifhorn, Germany
2
Leichtweiß-Institut für Wasserbau, Technische Universitaet Braunschweig, 38106 Braunschweig, Germany
*
Author to whom correspondence should be addressed.
Water 2019, 11(6), 1253; https://doi.org/10.3390/w11061253
Received: 16 April 2019 / Revised: 29 May 2019 / Accepted: 11 June 2019 / Published: 14 June 2019
(This article belongs to the Special Issue Water-Worked Bedload: Hydrodynamic and Mass Transport)
Design guidelines were developed for a number of in-stream structures; however, the knowledge about their morphological and hydraulic function is still incomplete. A variant is submerged groynes, which aim to be applicable for bank protection especially in areas with restricted flood water levels due to their shallow height. Laboratory experiments were conducted to investigate the backwater effect and the flow resistance of submerged groyne fields with varying and constant field length and groyne distance. The effect of the shape of a groyne model was investigated using two types of groynes. The validity of different flow types, from “isolated roughness” to “quasi smooth”, was analyzed in relation to the roughness density of the groyne fields. The results show a higher backwater effect for simplified groynes made of multiplex plates, compared to groynes made of gravel. The relative increase of the upstream water level was lower at high initial water levels, for short length of the groyne field, and for larger distance between the single groynes. The highest roughness of the groyne fields was found at roughness densities, which indicated wake interference flow. Considering a mobile bed, the flow resistance was reduced significantly. View Full-Text
Keywords: in-stream structures; groyne field; groyne type; backwater effect; flow resistance; friction factor; flow type in-stream structures; groyne field; groyne type; backwater effect; flow resistance; friction factor; flow type
Show Figures

Figure 1

MDPI and ACS Style

Möws, R.; Koll, K. Roughness Effect of Submerged Groyne Fields with Varying Length, Groyne Distance, and Groyne Types. Water 2019, 11, 1253.

Show more citation formats Show less citations formats
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Back to TopTop