J. Hydrol. Hydromech., Vol. 65, No. 1, 2017, p. 1 - 17, doi: 10.1515/johh-2016-0051
Scientific Paper, English
Christian D. Guzman, Seifu A. Tilahun, Dessalegn C. Dagnew, Assefa D. Zegeye, Tigist Y. Tebebu, Birru Yitaferu, Tammo S. Steenhuis: Modeling sediment concentration and discharge variations in a small
Ethiopian watershed with contributions from an unpaved road
Full Text in PDF 86 DOWNLOADS
- Drainage of paved and unpaved roads has been implicated as a major contributor of overland flow and erosion
in mountainous landscapes. Despite this, few watershed models include or have tested for the effect roads have on discharge
and sediment loads. Though having a model is an important step, its proper application and attention to distinct
landscape features is even more important. This study focuses on developing a module for drainage from a road and tests
it on a nested watershed (Shanko Bahir) within a larger previously studied site (Debre Mawi) that receives overland flow
contributions from a highly compacted layer of soil on an unpaved road surface. Shanko Bahir experiences a sub-humid
monsoonal climate and was assessed for the rainy seasons of 2010, 2011, and 2012. The model chosen is the Parameter
Efficient Distributed (PED) model, previously used where saturation-excess overland flow heavily influences discharge
and sediment concentration variation, though infiltration-excess occasionally occurs. Since overland flow on unpaved
surfaces emulates Hortonian flow, an adjustment to the PED model (the developed module) advances possible incorporation
of both flow regimes. The modification resulted in similar modeling performance as previous studies in the Blue
Nile Basin on a daily basis (NSE = 0.67 for discharge and 0.71 for sediment concentrations). Furthermore, the road while
occupying a small proportion of the sub-watershed (11%) contributed importantly to the early discharge and sediment
transport events demonstrating the effect of roads especially on sediment concentrations. Considerations for the dynamic
erodibility of the road improved sediment concentration simulation further (NSE = 0.75). The results show that this PED
modeling framework can be adjusted to include unpaved compacted surfaces to give reasonable results, but more work is
needed to account for contributions from gullies, which can cause high influxes of sediment.
KEY WORDS: Saturation excess runoff; infiltration excess (Hortonian) runoff; soil erosion; Ethiopian highlands; PED model.
Address:
- Christian D. Guzman, Department of Biological and Environmental Engineering, Cornell University, Ithaca, 206 Riley Robb Hall, NY 14853-5701, USA.
- Seifu A. Tilahun, Faculty of Civil and Water Resources Engineering, Institute of Technology, Bahir Dar University, Bahir Dar, Ethiopia.
- Dessalegn C. Dagnew, Faculty of Civil and Water Resources Engineering, Institute of Technology, Bahir Dar University, Bahir Dar, Ethiopia.
- Assefa D. Zegeye, Department of Biological and Environmental Engineering, Cornell University, Ithaca, 206 Riley Robb Hall, NY 14853-5701, USA.
- Tigist Y. Tebebu, Department of Biological and Environmental Engineering, Cornell University, Ithaca, 206 Riley Robb Hall, NY 14853-5701, USA.
- Birru Yitaferu, Amhara Regional Agriculture Research Institute, Bahir Dar, Ethiopia.
- Tammo S. Steenhuis, Department of Biological and Environmental Engineering, Cornell University, Ithaca, 206 Riley Robb Hall, NY 14853-5701, USA. Faculty of Civil and Water Resources Engineering, Institute of Technology, Bahir Dar University, Bahir Dar, Ethiopia. (Corresponding author. Tel.:+1-607-255-2489 Fax.: Email: tss1@cornell.edu)
J. Hydrol. Hydromech., Vol. 65, No. 1, 2017, p. 18 - 25, doi: 10.1515/johh-2016-0047
Scientific Paper, English
Vu Thi Thom, Dao Nguyen Khoi, Do Quang Linh: Using gridded rainfall products in simulating streamflow in a tropical
catchment – A case study of the Srepok River Catchment, Vietnam
Full Text in PDF 79 DOWNLOADS
- The precise rainfall estimate with appropriate spatial and temporal resolutions is a key input to distributed hydrological
models. However, networks of rain gauges are often sparsely distributed in developing countries. To overcome
such limitations, this study used some of the existing gridded rainfall products to simulate streamflow. Four gridded
rainfall products, including APHRODITE, CFSR, PERSIANN, and TRMM, were used as input to the SWAT distributed
hydrological model in order to simulate streamflow over the Srepok River Catchment in Vietnam. Besides that,
the available rain gauges data were also used for comparison. Amongst the four different datasets, the TRMM and
APHRODITE data show their best match to rain gauges data in simulating the daily and monthly streamflow with satisfactory
precision in the 2000–2006 period. The result indicates that the TRMM and APHRODITE data have potential applications
in driving hydrological model and water resources management in data-scarce and ungauged areas in Vietnam.
KEY WORDS: APHRODITE; CFSR; PERSIANN; TRMM; Rainfall; Streamflow; SWAT model.
Address:
- Vu Thi Thom, Centre of Water Management and Climate Change, Vietnam National University – Ho Chi Minh City, Ho Chi Minh City, Vietnam.
- Dao Nguyen Khoi, Environmental Engineering and Management Research Group, Ton Duc Thang University, 19 Nguyen Huu Tho Street, Distric 7, Ho Chi
Minh City, Vietnam. Faculty of Environment and Labour Safety, Ton Duc Thang University, 19 Nguyen Huu Tho Street, District 7, Ho Chi Minh City,
Vietnam. Faculty of Environment, University of Science, Vietnam National University – Ho Chi Minh City, Ho Chi Minh City, Vietnam. (Corresponding author. Tel.: Fax.: Email: daonguyenkhoi@tdt.edu.vn; dnkhoi86@gmail.com)
- Do Quang Linh, Centre of Water Management and Climate Change, Vietnam National University – Ho Chi Minh City, Ho Chi Minh City, Vietnam.
J. Hydrol. Hydromech., Vol. 65, No. 1, 2017, p. 26 - 34, doi: 10.1515/johh-2016-0048
Scientific Paper, English
Aysegul Ozgenc Aksoy, Gokcen Bombar, Tanil Arkis, Mehmet Sukru Guney: Study of the time-dependent clear water scour around circular bridge piers
Full Text in PDF 44 DOWNLOADS
- The local scour around bridge piers influences their stabilities and plays a key role in the bridge failures. The
estimation of the maximum possible scour depth around bridge piers is an important step in the design of the bridge pier
foundations. In this study, the temporal evolution of local scour depths as well as the equilibrium scour depths were analyzed.
The experiments were carried out in a rectangular flume by using uniform sediment with median diameter of 3.5 mm
and geometric standard deviation of 1.4. The diameters of the tested circular bridge piers were 40 mm, 80 mm, 150 mm
and 200 mm. The flow and scour depths were determined by ultrasonic sensors. The experiments were realized in clear
water conditions with various constant flow rates.
The experimental findings were compared with those calculated from some empirical equations existing in the literature.
A new empirical relation involving the flow intensity, the relative water depth and the dimensionless time is also introduced.
The advantage of this proposed relation is that the only parameter requiring the calculation is the critical velocity,
other parameters being known geometric and hydraulic parameters. The performance of this relation was tested by
using experimental data available in the literature, and a satisfactory compatibility was revealed between the experimental
and numerical results.
KEY WORDS: Bridge pier; Clear-water scour; Local scour; Steady flow; Temporal evolution.
Address:
- Aysegul Ozgenc Aksoy, Civil Engineering Department, Dokuz Eylul University, Tinaztepe Campus, Izmir, Turkey. (Corresponding author. Tel.:00902323017054 Fax.: Email: aysegul.ozgenc@deu.edu.tr)
- Gokcen Bombar, Civil Engineering Department, Ege University, Bornova, Izmir, Turkey.
- Tanil Arkis, Civil Engineering Department, Dokuz Eylul University, Tinaztepe Campus, Izmir, Turkey.
- Mehmet Sukru Guney, Civil Engineering Department, Dokuz Eylul University, Tinaztepe Campus, Izmir, Turkey.
J. Hydrol. Hydromech., Vol. 65, No. 1, 2017, p. 35 - 48, doi: 10.1515/johh-2016-0044
Scientific Paper, English
Prashanth Reddy Hanmaiahgari, Vesselina Roussinova, Ram Balachandar: Turbulence characteristics of flow in an open channel with temporally varying mobile bedforms
Full Text in PDF 48 DOWNLOADS
- Turbulence of flow over mobile bedforms in natural open channels is not yet clearly understood. An attempt is made in this paper to determine the effect of naturally formed mobile bedforms on velocities, turbulent intensities and turbulent stresses. Instantaneous velocities are measured using a two-dimensional particle image velocimetry (PIV) to evaluate the turbulence structure of free surface flow over a fixed (immobile) bed, a weakly mobile bed and a temporally varying mobile bed with different stages of bedform development. This paper documents the vertical distribution of ve-locity, turbulence intensities, Reynolds shear stress and higher-order moments including skewness and turbulent diffu-sion factors. Analysis of the velocity distributions shows a substantial decrease of velocity near the bed with increasing bedform mobility due to increased friction. A modified logarithmic law with a reduced von Kármán constant and in-creased velocity shift is proposed for the case of the mobile bedforms. A significant increase in the Reynolds shear stress is observed in the mobile bedforms experiments accompanied by changes over the entire flow depth compared to an im-mobile bed. The skewness factor distribution was found to be different in the case of the flow over the mobile bedforms. All higher-order turbulence descriptors are found to be significantly affected by the formation of temporally varying and non-equilibrium mobile bedforms. Quadrant analysis indicates that sweep and outward events are found to be dominant in strongly mobile bedforms and govern the bedform mobility.
KEY WORDS: Turbulence; Open channel; Bedforms; Higher-order moments; PIV; Quadrant analysis.
Address:
- Prashanth Reddy Hanmaiahgari, Department of Civil Engineering, IIT Kharagpur, Kharagpur, 721302, India. (Corresponding author. Tel.: Fax.: Email: hpr@civil.iitkgp.ernet.in)
- Vesselina Roussinova, Department of Mechanical Engineering, University of Windsor, Windsor, ON, N9B 3P4, Canada.
- Ram Balachandar, Department of Civil and Environmental Engineering, University of Windsor, Windsor, ON, N9B 3P4, Canada.
J. Hydrol. Hydromech., Vol. 65, No. 1, 2017, p. 49 - 59, doi: 10.1515/johh-2016-0039
Scientific Paper, English
Nino Krvavica, Ivica Kožar, Vanja Travaš, Nevenka Ožanić: Numerical modelling of two-layer shallow water flow in microtidal
salt-wedge estuaries: Finite volume solver and field validation
Full Text in PDF 56 DOWNLOADS
- A finite volume model for two-layer shallow water flow in microtidal salt-wedge estuaries is presented in this work. The
governing equations are a coupled system of shallow water equations with source terms accounting for irregular channel geometry
and shear stress at the bed and interface between the layers. To solve this system we applied the Q-scheme of Roe with suitable
treatment of source terms, coupling terms, and wet-dry fronts. The proposed numerical model is explicit in time, shock-capturing
and it satisfies the extended conservation property for water at rest. The model was validated by comparing the steady-state solutions
against a known arrested salt-wedge model and by comparing both steady-state and time-dependant solutions against field
observations in Rječina Estuary in Croatia. When the interfacial friction factor λi was chosen correctly, the agreement between
numerical results and field observations was satisfactory.
KEY WORDS: Finite volume method; Q-schemes; Salt-wedge estuaries; Two-layer flows; Shallow water equations; Rječina Estuary.
Address:
- Nino Krvavica, Department of Hydrology and Hydraulic Engineering, Faculty of Civil Engineering, University of Rijeka, Radmile Matejčić 3, 51000
Rijeka, Croatia.
- Ivica Kožar, Department of Computer Modeling, Faculty of Civil Engineering, University of Rijeka, Radmile Matejčić 3, 51000 Rijeka, Croatia. (Corresponding author. Tel.:+385 51 265 993 Fax.: +385 51 265 998 Email: ivica.kozar@uniri.hr)
- Vanja Travaš, Department of Hydrology and Hydraulic Engineering, Faculty of Civil Engineering, University of Rijeka, Radmile Matejčić 3, 51000
Rijeka, Croatia.
- Nevenka Ožanić, Department of Hydrology and Hydraulic Engineering, Faculty of Civil Engineering, University of Rijeka, Radmile Matejčić 3, 51000
Rijeka, Croatia.
J. Hydrol. Hydromech., Vol. 65, No. 1, 2017, p. 60 - 67, doi: 10.1515/johh-2016-0052
Scientific Paper, English
Sudarshan Patowary, Arup Kumar Sarma: A modified hydrodynamic model for routing unsteady flow in a river having
piedmont zone
Full Text in PDF 35 DOWNLOADS
- Existence of piedmont zone in a river bed is a critical parameter from among numerous variations of topographical,
geological and geographical conditions that can significantly influence the river flow scenario. Downstream
flow situation assessed by routing of upstream hydrograph may yield higher flow depth if existence of such high infiltration
zone is ignored and therefore it is a matter of concern for water resources planning and flood management. This
work proposes a novel modified hydrodynamic model that has the potential to accurately determine the flow scenario in
presence of piedmont zone. The model has been developed using unsteady free surface flow equations, coupled with
Green-Ampt infiltration equation as governing equation. For solution of the governing equations Beam and Warming
implicit finite difference scheme has been used. The proposed model was first validated from the field data of Trout
Creek River showing excellent agreement. The validated model was then applied to a hypothetical river reach commensurate
with the size of major tributaries of Brahmaputra Basin of India. Results indicated a 10% and 14% difference in
the maximum value of discharge and depth hydrograph in presence and absence of piedmont zone respectively. Overall
this model was successfully used to accurately predict the effect of piedmont zone on the unsteady flow in a river.
KEY WORDS: Groundwater flow; Numerical modeling; Piedmont zone; Green-Ampt. Equation; Surface water equation.
Address:
- Sudarshan Patowary, Dept. of Civil Engineering, Indian Institute of Technology, Guwahati, India. (Corresponding author. Tel.:09706830528 Fax.: Email: s.patowary@iitg.ernet.in)
- Arup Kumar Sarma, Dept. of Civil Engineering, Indian Institute of Technology, Guwahati, India. E-mail: aks@iitg.ernet.in
J. Hydrol. Hydromech., Vol. 65, No. 1, 2017, p. 68 - 79, doi: 10.1515/johh-2016-0046
Scientific Paper, English
Zenghui Wang, Junqiang Xia, Shanshan Deng, Junhua Zhang, Tao Li: One-dimensional morphodynamic model coupling open-channel flow and
turbidity current in reservoir
Full Text in PDF 45 DOWNLOADS
- Traditional depth-averaged morphodynamic models for turbidity currents usually focus on the propagation of
currents after plunging. However, owing to the unsteady characteristic of the plunge point locations and the tough conditions
of field measurement within the plunge zone in a reservoir, it is difficult in practice to directly provide upstream
boundary conditions for these models. A one-dimensional (1D) morphodynamic model coupling open-channel flow and
turbidity current in a reservoir was proposed to simulate the whole processes of turbidity current evolution, from formation
and propagation to recession. The 1D governing equations adopted are applicable to open-channel flows and turbidity
currents over a mobile bed with irregular cross-section geometry. The coupled solution is obtained by a two-step
calculation mode which alternates the calculations of open-channel flow and turbidity current, and a plunge criterion is
used to determine the location of the upstream boundary for the turbidity current, and to specify the corresponding
boundary conditions. This calculation mode leads to consecutive predictions of the hydrodynamic and morphological
factors, from the open-channel reach to the turbidity current reach. Turbidity current events in two laboratory experiments
with different set-ups were used to test the capabilities of the proposed model, with the effect of free-surface gradient
also being investigated. A field-scale application of the coupled model was conducted to simulate two turbidity current
events occurring in the Sanmenxia Reservoir, and the method for calculating the limiting height of aspiration was
adopted to estimate the outflow discharge after the turbidity currents arrived in front of the dam. The predicted plunge
locations and arrival times at different cross-sections were in agreement with the measurements. Moreover, the calculated
interface evolution processes and the sediment delivery ratios also agreed generally with the observed results. Therefore,
the 1D morphodynamic model proposed herein can help to select the design capacity of the outlets, and optimize
the procedure for sediment release in reservoirs.
KEY WORDS: Turbidity current; Open-channel flow; Coupled solution; Morphodynamic model; Plunge point; Reservoir.
Address:
- Zenghui Wang, State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, 430072 Wuhan, China.
- Junqiang Xia, State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, 430072 Wuhan, China. (Corresponding author. Tel.: Fax.: Email: xiajq@whu.edu.cn)
- Shanshan Deng, State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, 430072 Wuhan, China.
- Junhua Zhang, Yellow River Institute of Hydraulic Research, YRCC, 450003 Zhengzhou, China.
- Tao Li, Yellow River Institute of Hydraulic Research, YRCC, 450003 Zhengzhou, China.
J. Hydrol. Hydromech., Vol. 65, No. 1, 2017, p. 80 - 87, doi: 10.1515/johh-2016-0054
Scientific Paper, English
Zofia Zięba: Influence of soil particle shape on saturated hydraulic conductivity
Full Text in PDF 40 DOWNLOADS
- The aim of this paper is to define the correlation between the geometry of grains and saturated hydraulic conductivity
of soils. The particle shape characteristics were described by the ζ0C index (Parylak, 2000), which expresses the
variability of several shape properties, such as sphericity, angularity and roughness.
The analysis was performed on samples of four soils, which were characterised by the same grain size distribution and
extremely different particle structure. The shape characteristics varied from ideally spherical, smooth grains (glass microbeads
GM) to highly irregular and rough particles (fly ash FA).
For each soil, laboratory tests of saturated hydraulic conductivity (constant head test CHT and falling head test FHT)
were performed. Additionally, an empirical analysis of effective pore diameter was conducted with use of the analytical
models developed by Pavchich (Wolski, 1987) and Indraratna and Vafai (1997). The models were modified by introducing
the ζ0C index.
Experiments have shown that saturated hydraulic conductivity depends on grains shape and surface roughness. This
parameter decreases with the increase in the irregularity of soil particles. Moreover, it was proven that the ζ0C reflects the
relationship between effective pore diameter and grain shape characteristics.
KEY WORDS: Particle shape; Saturated hydraulic conductivity; Effective pore diameter.
Address:
- Zofia Zięba, Institute of Building Engineering, Wrocław University of Environmental and Life Sciences, 24 Grunwaldzki Sq., 50-363 Wrocław, Poland. (Corresponding author. Tel.:+48 71 320 55 43 Fax.: +48 71 320 55 84 Email: zofia.zieba@up.wroc.pl)
J. Hydrol. Hydromech., Vol. 65, No. 1, 2017, p. 88 - 98, doi: 10.1515/johh-2016-0053
Scientific Paper, English
Klaas Oostindie, Louis W. Dekker, Jan G. Wesseling, Violette Geissen, Coen J. Ritsema: Impacts of grass removal on wetting and actual water repellency in a sandy soil
Full Text in PDF 35 DOWNLOADS
- Soil water content and actual water repellency were assessed for soil profiles at two sites in a bare and grass-covered plot of a sand pasture, to investigate the impact of the grass removal on both properties. The soil of the plots was sampled six times in vertical transects to a depth of 33 cm between 23 May and 7 October 2002. On each sampling date the soil water contents were measured and the persistence of actual water repellency was determined of field-moist samples. Considerably higher soil water contents were found in the bare versus the grass-covered plots. These alterations are caused by differences between evaporation and transpiration rates across the plots. Noteworthy are the often excessive differences in soil water content at depths of 10 to 30 cm between the bare and grass-covered plots. These differences are a consequence of water uptake by the roots in the grass-covered plots. The water storage in the upper 19 cm of the bare soil was at least two times greater than in the grass-covered soil during dry periods. A major part of the soil profile in the grass-covered plots exhibited extreme water repellency to a depth of 19 cm on all sampling dates, while the soil profile of the bare plots was completely wettable on eight of the twelve sampling dates. Significant differences in persistence of actual water repellency were found between the grass-covered and bare plots.
KEY WORDS: Actual soil water repellency; Critical soil water content; Irregular wetting; Preferential flow; Transition zone; Water drop penetration time (WDPT) test.
Address:
- Klaas Oostindie, Wageningen University and Research, Alterra, Soil Physics and Land Use Team, P.O. Box 47, 6700 AA, Wageningen, the Netherlands. Wageningen University and Research, Soil Physics and Land Management Group, P.O. Box 47, 6700 AA, Wageningen, the Netherlands.
- Louis W. Dekker, Wageningen University and Research, Alterra, Soil Physics and Land Use Team, P.O. Box 47, 6700 AA, Wageningen, the Netherlands. Wageningen University and Research, Soil Physics and Land Management Group, P.O. Box 47, 6700 AA, Wageningen, the Netherlands. (Corresponding author. Tel.: Fax.: Email: louis.dekker@wur.nl)
- Jan G. Wesseling, Wageningen University and Research, Alterra, Soil Physics and Land Use Team, P.O. Box 47, 6700 AA, Wageningen, the Netherlands. Wageningen University and Research, Soil Physics and Land Management Group, P.O. Box 47, 6700 AA, Wageningen, the Netherlands.
- Violette Geissen, Wageningen University and Research, Soil Physics and Land Management Group, P.O. Box 47, 6700 AA, Wageningen, the Netherlands.
- Coen J. Ritsema, Wageningen University and Research, Soil Physics and Land Management Group, P.O. Box 47, 6700 AA, Wageningen, the Netherlands.
J. Hydrol. Hydromech., Vol. 65, No. 1, 2017, p. 99 - 104, doi: 10.1515/johh-2016-0055
Scientific Paper, English
Nasrollah Sepehrnia, Mohammad Ali Hajabbasi, Majid Afyuni, Ľubomír Lichner: Soil water repellency changes with depth and relationship to physical
properties within wettable and repellent soil profiles
Full Text in PDF 81 DOWNLOADS
- This study explored the effect of soil water repellency (SWR) on soil hydrophysical properties with depth.
Soils were sampled from two distinctly wettable and water repellent soil profiles at depth increments from 0–60 cm. The
soils were selected because they appeared to either wet readily (wettable) or remain dry (water repellent) under field
conditions. Basic soil properties (MWD, SOM, θ
v) were compared to hydrophysical properties (Ks, Sw, Se, Sww, Swh,
WDPT, RIc, RIm and WRCT) that characterise or are affected by water repellency. Our results showed both soil and
depth affected basic and hydrophysical properties of the soils (p <0.001). Soil organic matter (SOM) was the major property
responsible for water repellency at the selected depths (0–60). Water repellency changes affected moisture distribution
and resulted in the upper layer (0–40 cm) of the repellent soil to be considerably drier compared to the wettable soil.
The water repellent soil also had greater MWDdry and Ks over the entire 0–60 cm depth compared to the wettable soil.
Various measures of sorptivity, Sw, Se, Sww, Swh, were greater through the wettable than water repellent soil profile, which
was also reflected in field and dry WDPT measurements. However, the wettable soil had subcritical water repellency, so
the range of data was used to compare indices of water repellency. WRCT and RIm had less variation compared to WDPT
and RIc. Estimating water repellency using WRCT and RIm indicated that these indices can detect the degree of SWR and
are able to better classify SWR degree of the subcritical-repellent soil from the wettable soil.
KEY WORDS: Soil property; Soil organic matter; Aggregate; Bulk density; Mean weight diameter; Infiltration; Water repellency.
Address:
- Nasrollah Sepehrnia, Department of Soil Science, College of Agriculture, Isfahan University of Technology, Isfahan, 84156-83111, Iran. (Corresponding author. Tel.:+983133913471 Fax.: +983133913471 Email: n.sepehrnia@ag.iut.ac.ir)
- Mohammad Ali Hajabbasi, Department of Soil Science, College of Agriculture, Isfahan University of Technology, Isfahan, 84156-83111, Iran.
- Majid Afyuni, Department of Soil Science, College of Agriculture, Isfahan University of Technology, Isfahan, 84156-83111, Iran.
- Ľubomír Lichner, Institute of Hydrology, Slovak Academy of Sciences, Dúbravská cesta 9, 841 04 Bratislava, Slovakia.