Journal of Irrigation and Drainage Engineering: Recent submissions
Now showing items 2761-2780 of 3826
-
Theoretical Justification of SCS Method for Runoff Estimation
(American Society of Civil Engineers, 1998)The Soil Conservation Service (SCS) method is widely used to estimate runoff from small- to medium-sized watersheds. The most critical assumption of the SCS method is that the ratio of the actual retention to the potential ... -
Generalized Culvert Design Diagram
(American Society of Civil Engineers, 1998)The features of culvert flow in a basic arrangement are highlighted. Four fundamental flow types may be identified, namely critical flow, uniform flow, gated flow, and pressurized flow. A generalized design diagram is ... -
Gradually Varied Flow Solutions in Newton-Raphson Form
(American Society of Civil Engineers, 1998)Numerical solutions in Newton-Raphson form are presented for the standard step method of calculating the free surface profile in a gradually varied flow. The solutions are based on three different resistance equations: ... -
Discussion and Closure: Response of Unconfined Aquifer to Sudden Change in Boundary Head
(American Society of Civil Engineers, 1998) -
Error Analysis of Flowmeter Measurements
(American Society of Civil Engineers, 1998)It is commonly recommended that a straight section of pipe, 8–10 pipe diameters long, be installed immediately upstream from a flowmeter to reduce errors in flow rate measurements due to excessive turbulence. However, this ... -
Discussion and Closure: Use of Rubber Dams for Flood Mitigation in Hong Kong
(American Society of Civil Engineers, 1998) -
Nonhydrostatic Model for Surface Irrigation
(American Society of Civil Engineers, 1998)A nonhydrostatic model for overland flow is developed for the purpose of providing the framework for predicting the fate and transport of chemicals under surface irrigation. The technique is based on the turbulent Navier-Stokes ... -
Measuring Droplet Impact Energy with Piezoelectric Film
(American Society of Civil Engineers, 1998)A system for measuring water droplet impact energy is described, which consists of piezoelectric film connected to a high-speed data acquisition board in a personal computer. The system converts the impact forces of ... -
Spatial Modeling of Soil Properties for Subsurface Drainage Projects
(American Society of Civil Engineers, 1998)Selecting areas for a subsurface drainage system and the proper design of such a system require sufficient and reliable soil data, which are inherently variable in both space and time. This study shows how geostatistical ... -
PILOTE: Linear Quadratic Optimal Controller for Irrigation Canals
(American Society of Civil Engineers, 1998)Linear quadratic optimal control theory is applied to the automatic control of two different eight-pool irrigation canals. The model used to design the controller is derived from the Saint-Venant equations discretized ... -
Editorial
(American Society of Civil Engineers, 1998) -
Refining the Definition of Field Capacity in the Literature
(American Society of Civil Engineers, 1998)The normalized water content calculated with the simple algebraic equation Θ -
Estimation of Surface Volume in Hydrological Models for Border Irrigation
(American Society of Civil Engineers, 1998)A procedure was developed to obtain better estimations of the surface volumes than in hydrological models and more rapid results than running zero inertia models. Using a zero inertia model, a database was created of the ... -
Side-Weir Flow in Curved Channels
(American Society of Civil Engineers, 1998)Side-weirs located on straight channels have attracted considerable interest and research effort. The same, however, is not true for side-weirs on curved channels. The existing studies deal mainly with sediment transport ... -
Two-Phase-Reactive Solute-Transport Simulation in Unsaturated Zone
(American Society of Civil Engineers, 1998)A numerical model is developed for the simulation of vertical unsteady-state, two-phase reactive solute-transport through the unsaturated zone. Advective transport is simulated using the method of characteristics, whereas ... -
Effective Erosion Parameters for Slopes with Spatially Varying Properties
(American Society of Civil Engineers, 1998)Overland flow erosion has a significant role in determining the drainage properties of a land surface. Most physically based models of soil erosion over hillslopes use a constant value of critical shear stress τ -
Modeling the Heat Sense Flowmeter
(American Society of Civil Engineers, 1998)Real-time measurement of velocities in porous media is desirable for engineers engaged in ground-water remediation, monitoring projects, drainage studies, etc. This paper investigates the theory supporting the heat sense ... -
Overflow Characteristics of Circular Weirs: Effects of Inflow Conditions
(American Society of Civil Engineers, 1998)The most common types of weirs are the broad-crested weir, the sharp-crested weir, the circular-crested weir, and nowadays, the ogee crest weir. Advantages of the cylindrical weir shape include the stable overflow pattern, ... -
Flow Characteristics of Chimney Weir under Submergence
(American Society of Civil Engineers, 1998)A theoretical submerged flow equation for chimney weir is developed. Based on experiments conducted with five different chimney weirs, it is found that the theoretical submerged flow equation, along with a parabolic equation ... -
Global Identification of Surface Irrigation Parameters
(American Society of Civil Engineers, 1998)A numerical method is developed for the identification of bed resistance and infiltration parameters in surface irrigation based on global procedures. The method is characterized by global convergence—a unique solution ...