Please use this identifier to cite or link to this item: https://hdl.handle.net/11147/4931
Title: Experimental and numerical investigation of bed-load transport under unsteady flows
Authors: Bombar, Gökçen
Elçi, Şebnem
Tayfur, Gökmen
Güney, M. Şükrü
Bor, Aslı
Keywords: Bed load
Diffusion wave
Kinematic wave theory
Numerical model
Sediment transport
Issue Date: Nov-2011
Publisher: American Society of Civil Engineers (ASCE)
Source: Bombar, G., Elçi, Ş., Tayfur, G., Güney, M. Ş., and Bor, A. (2011). Experimental and numerical investigation of bed-load transport under unsteady flows. Journal of Hydraulic Engineering, 137(10) , 1276-1282. doi:10.1061/(ASCE)HY.1943-7900.0000412
Abstract: The dynamic behavior of bed-load sediment transport under unsteady flow conditions is experimentally and numerically investigated. A series of experiments are conducted in a rectangular flume (18 m in length, 0.80 m in width) with various triangular and trapezoidal shaped hydrographs. The flume bed of 8 cm in height consists of scraped uniform small gravel of D 50=4.8 mm. Analysis of the experimental results showed that bed-load transport rates followed the temporal variation of the triangular and trapezoidal hydrographs with a time lag on the average of 11 and 30 s, respectively. The experimental data were also qualitatively investigated employing the unsteady-flow parameter and total flow work index. The analysis results revealed that total yield increased exponentially with the total flow work. An original expression which is based on the net acceleration concept was proposed for the unsteadiness parameter. Analysis of the results then revealed that the total yield increased exponentially with the increase in the value of the proposed unsteadiness parameter. Further analysis of the experimental results revealed that total flow work has an inverse exponential variation relation with the lag time. A one-dimensional numerical model that employs the governing equations for the conservation of mass for water and sediment and the momentum was also developed to simulate the experimental results. The momentum equation was approximated by the diffusion wave approach, and the kinematic wave theory approach was employed to relate the bed sediment flux to the sediment concentration. The model successfully simulated measured sedimentographs. It predicted sediment yield, on the average, with errors of 7% and 15% of peak loads for the triangular and trapezoidal hydrograph experiments, respectively.
URI: http://doi.org/10.1061/(ASCE)HY.1943-7900.0000412
http://hdl.handle.net/11147/4931
ISSN: 0733-9429
0733-9429
Appears in Collections:Civil Engineering / İnşaat Mühendisliği
Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection
WoS İndeksli Yayınlar Koleksiyonu / WoS Indexed Publications Collection

Files in This Item:
File Description SizeFormat 
4931.pdfMakale603.1 kBAdobe PDFThumbnail
View/Open
Show full item record

CORE Recommender

Google ScholarTM

Check

Altmetric


Items in GCRIS Repository are protected by copyright, with all rights reserved, unless otherwise indicated.