Thermodynamic Factors in Evapotranspiration
Many of the methods discussed in this paper are refinements of procedures presented in the report 'Consumptive Use of Water and Irrigation Water Requirements'...
Calibration of an Evapotranspiration Model Using Eddy Correlation Methods
An evapotranspiration (ET) prediction model was developed by calibrating the H. L. Penman equation for an alfalfa reference crop in the southwestern Oklahoma region. Evaporative flux for...
Factors Influencing Conveyance Efficiency
Losses from a water distribution system are inadequately defined by reference to only the gross conveyance efficiency (Ec) of the system. The various unavoidable and avoidable losses that...
Reservoirs Help On-Farm Operation and Automation
Reservoirs can be used to convert a less desirable set of flow rates and durations into a more desirable and flexible set of rates and durations. This will permit irrigation management...
Comparison of Surge and Continuous Flow Irrigation in California
With the closure of the Kesterson National Wildlife Refuge to drainwater disposal and the pending limits on tailwater flows to the San Joaquin River, decreasing deep percolation is of...
Tailwater Management with Surge Irrigation
Field data of surge irrigation has shown that, in the post-advance stage, there exists an optimum post-advance cycle time. Cycle time greater than or less than the optimum post-advance...
Infiltration as a Dependent Variable in Modeling Furrow Irrigation
Most surface irrigation models assume that infiltration is independent of surface flow hydraulics. However, wetted perimeter has been shown to significantly affect infiltration in furrows....
Steady State Fluid Transport Model for Plants
Knowledge of water potentials throughout the xylem and phloem elements as well as in individual cells is fundamental for understanding effects of water and temperature stress on transport...
Estimation of Mean Water Depth for Border Irrigation
The mean water depth for border irrigation is derived, using dam-break simple wave solution and boundary layer theory, as a function of inflow discharge, bottom slope, bottom roughness,...
Evaluation of Basin-Furrow Irrigation Systems
The division of the total flow into basin-furrows is analyzed using both energy and momentum principles. A zero-inertia model is applied to simulate the advance phase using different infiltration...
Estimating Number and Duration of On-Times for Surge Irrigation
Research shows surge flow can achieve efficient and uniform irrigation on some soils. However, most available information focuses on computerized analysis and modeling for research purposes....
Investigation of Main Supply Canal and Lateral Fluctuations
The Imperial Irrigation District and the U. S. Water Conservation Laboratory of Phoenix, Arizona are conducting a joint project to study the causes and effects of water level fluctuations...
Rating Curves for Adjustable Tricklers
This paper presents the approach and results of evaluating adjustable drip/trickle emitters to obtain rating curves. The emitter discharge depends on both system pressure and emitter opening...
Surge Flow?Automation of Surface Irrigation?At Last
The studies which led to the development of Surge Flow at Utah State University, began as an effort to automate surface irrigation systems. The first prototype models, were electric control...
Theoretical Flow Model for Drop Structures
A theoretical model based on the momentum equation is reviewed for a trapezoidal weir drop structure operating in a trapezoidal channel. Preliminary qualitative results indicate agreement...
Flutter Derivatives from 14 Generic Deck Sections
The results of a series of wind-tunnel bridge-deck section-model experiments are discussed. Fourteen section models, seven with H-shaped cross-sections and seven with rectangular cross-sections,...
Wind Tunnel Investigation of a Twin Deck Suspension Bridge
Wind tunnel measurements of the response of a twin deck suspension bridge to dynamic wind loads are presented. The investigation was concerned with the determination of the deck response...
Safety of Long Span Highway Bridges Based on Dynamic Response
This paper consists of an analytical study regarding the dynamic response of highway bridges subjected to heavy vehicle loads, with emphasis on long span low fundamental frequency bridges....
Furrow Modeling with Variable Hydraulic Characteristics
A zero inertia furrow irrigation model was developed to run on an IBM-compatible micro-computer. The depth gradient term of the momentum equation is approximated by averaging over the...
Are Soil Moisture Accounting Models Needed for the Real Time Forecasting of River Flows?
The difficulties inherent in using conceptual rainfall-runoff models in conjunction with filtering techniques, for the real time forecasting of river flows, are reviewed. The issue of...
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