scholarly journals Emulation of the Saint Venant Equations Enables Rapid and Accurate Predictions of Infiltration and Overland Flow Velocity on Spatially Heterogeneous Surfaces

2019 ◽  
Vol 55 (8) ◽  
pp. 7108-7129 ◽  
Author(s):  
Octavia Crompton ◽  
Anneliese Sytsma ◽  
Sally Thompson
Keyword(s):  
Flow Velocity ◽  
Overland Flow ◽  
Heterogeneous Surfaces ◽  
Saint Venant Equations

scholarly journals Seasonal vegetation and management influence overland flow velocity and roughness in upland grasslands

2020 ◽  
Vol 34 (18) ◽  
pp. 3777-3791
Author(s):  
Stephanie Bond ◽  
Mike J. Kirkby ◽  
Jean Johnston ◽  
Alistair Crowle ◽  
Joseph Holden
Keyword(s):  
Flow Velocity ◽  
Overland Flow

Experimental study of sediment transport processes and size selectivity of eroded sediment on steep Pisha sandstone slopes

2020 ◽  
Author(s):  
Pan Zhang ◽  
Pingqing Xiao ◽  
Chunxia Yang
Keyword(s):  
Sediment Transport ◽  
Flow Velocity ◽  
Overland Flow ◽  
Yellow River ◽  
Transport Processes ◽  
The Yellow River ◽  
Size Selectivity ◽  
Coarse Sediment ◽  
Sediment Particles ◽  
Slope Flow

<p>The Pisha sandstone area on the Ordos Plateau of China is the primary source of coarse sediment of the Yellow River. Sediment size distribution and selectivity greatly affect sediment transport and deposition. Hence, sediment transport processes and size selectivity by overland flow on Pisha sandstone slopes were investigated in this study. Experiments were run with Pisha sandstone soil (bulk density of 1.35 g/cm<sup>3</sup>) under rainfall intensities of 87 and 133 mm/h with a 25° slope gradient, and the duration of simulated rainfall is 1 h. Sediment and runoff were sampled at 2-min intervals to examine the size distribution change of the eroded sediment. The particle composition, enrichment rate, fractal dimension, and time distribution characteristics of median grain size (d<sub>50</sub>) of eroded sediment were comprehensively analyzed. Statistical analyses showed that the erosion process of Pisha sandstone slope mainly transported coarse sediment. More than 40% of eroded sediment particles were coarse sediment, which will become the main sediment in the lower reaches of the Yellow River bed. The particle size of eroded sediment tended to gradually decrease with the continuous rainfall but remained larger than the background value of Pisha sandstone soil after refinement. The fractal dimension was positively correlated with the slope flow velocity, while the d<sub>50</sub> was negatively correlated with the slope flow velocity. Overall, these findings show a strong relationship between the sediment transport and flow velocity, which indicates that the selectivity and transportation of sediment particles on the Pisha sand slopes is mainly influenced by the hydrodynamic parameters of overland flow. This study provides a methodology and data references for studying the particle selectivity characteristics of eroded sediment and provides a scientific basis for revealing the mechanism of erosion and sediment yield in the Pisha sandstone area of China.</p>

scholarly journals Modeling Surface Runoff

1995 ◽  
Vol 26 (3) ◽  
pp. 205-222 ◽  
Author(s):  
Harri Koivusalo ◽  
Tuomo Karvonen
Keyword(s):  
Transfer Function ◽  
Surface Runoff ◽  
Overland Flow ◽  
Physical Models ◽  
Transfer Function Model ◽  
Function Model ◽  
Fixed Parameter ◽  
Saint Venant Equations ◽  
Event Based ◽  
Runoff Events

The objective of this study was to compare approaches to modeling surface runoff due to summer and autumn storms on a cultivated field. The data consisted of measurements performed every 15 minutes during rainfall-surface runoff events in 1993. A transfer function model was formulated using measured rainfall or rainfall excess as an input and surface runoff as an output. The physical models were based on the kinematic wave approximation of the Saint Venant equations. Surface runoff was assumed to flow first as an overland flow on a level field and second in rills. The results showed that the transfer function model using rainfall excess as an input, and the implicitly solved rill flow model performed the best with respect to the fitness coefficients, which denoted the efficiency of the model. The testing of the models using fixed parameter combinations indicated that an event based parameter estimation was not applicable in verifying the models to changing conditions.

scholarly journals Hydraulic models for the simulation of flow routing in drainage canals

2013 ◽  
Vol 15 (3) ◽  
pp. 315-323 ◽  
Keyword(s):  
Wave Equations ◽  
Overland Flow ◽  
Agricultural Land ◽  
Kinematic Model ◽  
Flow Routing ◽  
Lateral Inflow ◽  
Drainage Canals ◽  
Saint Venant Equations ◽  
Junction Points ◽  
Complete Form

<p>In order to design a network of drainage canals, it is essential to consider the excess water from the agricultural land (overland flow) and to evaluate the characteristics of flow routing, such as the flow depths and discharges in the system of tertiary and main drainage canals of various order. In this paper models based on the Saint-Venant equations are presented, simulating the flow routing in a system of drainage canals. In these models, the lateral inflow towards tertiary drainage canals is the overland flow from adjacent fields. The Saint-Venant equations in their complete form (dynamic model) or in simplified forms, such as the diffusion wave equations (diffusion model) and the kinematic wave equations (kinematic model) are numerically solved by using the MacCormack explicit computational scheme which is a two-step predictor-corrector scheme, conditionally stable and convergent. In modeling flow through the system of drainage canals, emphasis was given to the simulation of flow at the junction points of two or more canals by applying the characteristic equations (negative and positive equations) in addition to the mass and energy conservation principles. Applications of the models for the simulation of flow within the system of drainage canals, subject to lateral inflow owing to overland flow, were also conducted in order to study the effect of various parameters of the drainage canals, on the hydrographs&rsquo; formation and also on the accuracy of the diffusion and kinematic equations in predicting flow in a drainage network.</p>

scholarly journals 1D/1D+2D integrated model for urban inundation calculation and application for Nhieu Loc – Thi Nghe basin (HCM city)

2014 ◽  
Vol 17 (1) ◽  
pp. 47-59
Author(s):  
Hong Thi My Tran ◽  
Giang Song Le
Keyword(s):  
Mathematical Model ◽  
Shallow Water ◽  
Finite Volume Method ◽  
Shallow Water Equations ◽  
Overland Flow ◽  
Integrated Model ◽  
One Dimensional ◽  
Saint Venant Equations ◽  
2D Flow ◽  
Volume Method

This paper presents a mathematical model for detailed calculate the flooding flow in NhieuLoc – ThiNghe basin. The flow in sewers is considered as one-dimensional while overland flow is modeled using the 1D+2D integrated model. 1D flow was calculated from the Saint – Venant equations and 2D flow was calculated from the shallow water equations. The finite volume method was used. The linkage of models was received a necessary consideration. The application for NhieuLoc – ThiNghe basin case showed that the model could respond to the practical requirements.

scholarly journals Overland flow velocity and roughness properties in peatlands

2008 ◽  
Vol 44 (6) ◽  
Author(s):  
Joseph Holden ◽  
Mike J. Kirkby ◽  
Stuart N. Lane ◽  
David G. Milledge ◽  
Chris J. Brookes ◽  
...  
Keyword(s):  
Flow Velocity ◽  
Overland Flow

scholarly journals Using thermal tracers to estimate flow velocities of shallow flows: laboratory and field experiments

2015 ◽  
Vol 63 (3) ◽  
pp. 255-262 ◽  
Author(s):  
Rui L.P. de Lima ◽  
João R.C.B. Abrantes ◽  
João L.M.P. de Lima ◽  
M. Isabel P. de Lima
Keyword(s):  
Flow Velocity ◽  
Field Experiments ◽  
Overland Flow ◽  
Velocity Estimation ◽  
Shallow Flow ◽  
Shallow Flows ◽  
Dye Tracer ◽  
Flow Surface ◽  
Infrared Technology ◽  
Hydrology And Water Resources

Abstract Accurate measurement of shallow flows is important for hydraulics, hydrology and water resources management. The objective of this paper is to discuss a technique for shallow flow and overland flow velocity estimation that uses infrared thermography. Laboratory flumes and different bare, vegetated and paved field surfaces were used to test the technique. Results show that shallow flow surface velocities estimated using thermal tracers and infrared technology are similar to estimates obtained using the Acoustic Doppler Velocimeter; similar results were also obtained for overland flow velocity estimates using thermography, here comparing with the dye tracer technique. The thermographic approach revealed some potential as a flow visualization technique, and leaves space for future studies and research.

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