Results 151 to 160 of about 110,951 (186)

Closed border irrigation evaluations

Agricultural Water Management, 1984
Abstract One hundred and thirty-four irrigations were evaluated, on 16 on-farm closed borders in southern New Mexico, over a 3-year period. Storage efficiencies, deep percolation efficiencies and loss ratios were the major performance parameters evaluated in the study.
openaire   +1 more source

Hydrograph Shape and Border Irrigation Efficiency

Journal of Irrigation and Drainage Engineering, 1995
Sloping borders with free outflow were studied to determine the effect of inflow hydrograph shape on maximum application efficiency. A zero-inertia model describing the movement of water along the border run with infiltration was used to predict the maximum application efficiency for five inflow hydrograph shapes.
A. A. Alazba, D. D. Fangmeier
openaire   +1 more source

Border-Irrigation Hydraulics with Zero Inertia

Journal of the Irrigation and Drainage Division, 1977
A mathematical model of the stream flow in border irrigation is presented in the context of negligible accelerations everywhere in the stream. During the advance phase, numerical solution of the governing equations is achieved on an oblique grid in the x-t plane.
Theodor Strelkoff, Nikolaos D. Katopodes
openaire   +1 more source

Performance Functions of Border Irrigation Systems

Journal of Irrigation and Drainage Engineering, 1988
A set of design functions that relate system performance to design variables in graded border irrigation was developed and verified. A dimensional analysis approach is used to combine the independent variables into a reduced number of independent dimensionless parameters.
Omnia El‐Hakim, W. Clyma, E. V. Richardson   +2 more
openaire   +1 more source

Simple Model of Border Irrigation

Journal of Irrigation and Drainage Engineering, 1986
This paper describes a numerical model for irrigation of sloping and level borders. The model solves the differential form of the combined equations for the conservation of mass and momentum with the acceleration terms removed. A finite difference scheme is used with the depth gradient term expressed explicitly and averaged over the entire wetted ...
openaire   +1 more source

Design procedure for border irrigation

Irrigation Science, 1997
An open-end graded border design procedure is presented. The proposed method based on the principle of mass conservation requires Kostiakov and Manning formulations for infiltration and roughness, respectively. The key assumption of the present design procedure is that the minimum infiltrated depth occurs at the lower border end and is equal to the ...
openaire   +1 more source

Complete Hydrodynamic Border-Strip Irrigation Model

Journal of Irrigation and Drainage Engineering, 1996
In this study, a hydrodynamic model is presented for simulating all the phases of border-strip irrigation. The explicit, second-order accurate MacCormack scheme is used for solving the governing equations of surface irrigation. In this method, the advance and recession fronts need not be considered explicitly and any infiltration equation can be ...
Vivekanand Singh, S. Murty Bhallamudi
openaire   +1 more source

Water front advance in irrigation borders

Journal of Agricultural Engineering Research, 1971
The time-distance relationship in water front advance is an important factor to be determined in designing an efficient border irrigation system. Water front advance in a border strip is a case of spatially varied unsteady flow with decreasing discharge.
A.M. Michael, A.C. Pandya
openaire   +1 more source

Dimensionless Solutions of Border-Irrigation Advance

Journal of the Irrigation and Drainage Division, 1977
The equations of border-irrigation flow are written in dimensionless form and solved numerically at three different levels of mathematical approximation. For the advance phase three independent parameters exist: the Froude number based on normal depth, the dimensionless exponent of the Kostiakov infiltration equation, and a dimensionless parameter ...
Nikolaos D. Katopodes, Theodor Strelkoff
openaire   +1 more source

Land Forming for Border Irrigation

Transactions of the ASAE, 1978
ABSTRACT AN earthwork-optimization technique, applicable to land grading for border irrigation, is presented. The method is developed for use with the digital computer using iterative application of least-squares principles to obtain an optimum field surface, based on minimizing the required volume of cut.
openaire   +1 more source