Erosion and deposition of sediment in rivers causes numerous problems. In order to describe this process, both the hydraulic properties of the river and the mechanics of sediment transport must be considered. This paper presents the development and application of a microcomputer program based on existing hydraulic and sediment transport theory. The model predicts erosion and deposition, estimates the total sediment load and size distribution, and determines the resulting change in channel geometry and slope.
This paper describes and compares the performance, application, and suitability of a microcomputer as host for the large-scale hydrologic model called SSARR. The SSARR Model is currently employed for operational forecasting in the Columbia River basin by the Corps of Engineers and National Weather Service. The principle host computer is an Amdahl 470V6 with IBM-MVS software. The micro-computer based version of SSARR was built from the same FORTRAN-77 source statements used on the Amdahl. A typical forecast simulation is presented as a case study for comparing execution by both the mainframe and micro computer.
Peaking plants pose a special problem for control. The new facilities are generally a very small part of a large system. Determination of the parameters necessary to run the plant to best advantage can be difficult for system operators. Normally, the operational philosophy of a peaking plant is to balance the inflows and outflows on a periodic basis, keeping the headwater level within a prescribed range. Microcomputers can aid in the control of unit start times, run times, and loading to maximize the desired output from the available water resource. This paper describes the use of a microcomputer for generation control at the North Hartland Dam Project, which is a daily peaking plant currently nearing completion in Vermont.
A three‐year study sponsored by the Empire State Electric Energy Research Corporation was conducted to determine the diversion efficiency and survival of adult and larval fish at a full‐scale angled screen demonstration facility located on the Hudson River estuary. A total of 59,309 fish were collected during the three‐year study, 99.4% from the diversion flow. Initial survival was 90.2%. Extended survival following a 96‐hr observation period was 35.3%. The angled‐screen system efficiency was 31.6%, increasing to 84.3% when corrected for collection and handling mortality. Ichthyoplankton diversion efficiency of 16.3% was inversely related to angled screen approach velocity and directly related to the size of the organism. Angled‐screen system efficiency for ichthyoplankton was 1.7%. The angled‐screen was judged to be successful for mitigating fish impingement. Ichthyoplankton study results indicate low diversion and high mortality, suggesting that angled screens are not effective for mitigating entrainment.
The paper reports on research that concerns the possible development of numerical models being able to simulate practical cases of Oil Spill Migration (OSPIM) in soils. Such models can provide important information concerning remedial measures required against the hazardous contamination caused by the oil spills. The study reported in this article consists of the following series of phases: Outlining of the general approach, laboratory experiments and justification of the general approach.
The Environmental Fluid Mechanics Laboratory (EFML) employs two computer systems for the purpose of data acquisition, analysis and control. The first, an HP-2100 system, is used primarily for data acquisition and the second, an HP-1000 system, is used for data reduction and interpretation and for experiment control. The paper describes the EFML computer system and its functions in terms of specific experiments in the turbulence modeling facility and in the natural lake model.
A regression model was developed for estimating the unit hydrograph for ungaged watersheds. The model uses physical characteristics of the drainage basin to predict the parameters needed to construct the unit hydrograph. Stepwise regression analysis was used to reduce the number of physical and hydrological data to four significant variables. The four variables are the area, height, length, and watershed slope. The two parameter gamma distribution function from the HYMO hydrologic model was selected for use in the study. The two parameters are the time to peak (t//p) and a recession constant (K). Equations for estimating t//p and K were developed in the study. Equations for t//p and K were incorporated into the microcomputer hydrologic program called the A&M Watershed Model.
The U. S. Army Engineer Waterways Experiment Station (WES) has used physical models to study sedimentation problems since 1931. With the recent advent of new technology, it was realized that these models, once adjusted, could be run using a computer to control the operation. Analyses suggested purchasing a business-oriented microcomputer and add an instrumentation interface to make it a process controller. To further enhance the automated model operation, microcomputers identical to those operating the models combined with digitizers and plotters have been purchased for the project engineers to use in data analysis and model design. This concept has been installed at the Inland Waterways Research Facility at the WES.
The locations of streamlines and equipotentials for two-dimensional flow in the vertical plane normal to a vertical retaining wall can be determined by various methods. Recent extension of the domain of definition of the dilogarithm to the entire complex plane by O. D. L. Strack has permitted the authors to develop an analytic solution describing the flow. This solution compares well with solutions determined graphically.
Energy dissipation in tidal waterways is estimated analytically by a harmonic method. Calibration of harmonic parameters is done through numerical simulation. Relations between tidal energy dissipation and macroscopic features of the physical system are obtained. The results are in agreement with the theory of homogeneous turbulence.
Extensive climatic data have been collected by the National Weather Service and other agencies, and are available in printed form or on magnetic tapes. The published data are expensive to work with, and the magnetic tapes require mainframe computers to be effectively utilized. Recent developments in microcomputers and in stochastic models of daily climatic phenomena combine to make delivery and use of daily climatic data much easier than in the past. This paper describes a system for delivering climatic information to users by means of an interactive microcomputer program. Data from the state of South Dakota are used as an example.
General characteristics of the MULTIPLAN spreadsheet and the TK! SOLVER equation solver are discussed. Subjects covered include capabilities, rules and techniques for developing models, and model applications. Use of the packages as educational tools is highlighted. One application of each package in water resources analyses is developed in some detail.
Draft tube aeration is one method for improving the dissolved oxygen content of hydroelectric discharges. A simple analytical procedure is presented for estimating the loss in turbine efficiency association with draft tube aeration. The calculation procedure is general and should have basic applicability to most draft tube aeration systems. Calculated efficiency losses are compared with measured efficiency loss values from operational systems.
The MINITAB statistical software project has been popularly used on mainframe computers since 1972. In June 1984, a subset of the program was made available for the IBM-PC microcomputer; it was designed for use with a numerical co-processor. A suite of BASIC and MINITAB macro programs have been written to conveniently investigate the correlation of sediment transport with the streampower of alluvial river flow. The field sediment data examined included recent measurements of bed and suspended load transport for 21 California streams. These are compared with recent laboratory data for the equilibrium transport of silt sized sediments. The graphic representation of the analyses uses the MICROSOFT Chart Program.
Cedar Bluff Reservoir is located on the Smoky Hill River near Arnold, Kansas, with a drainage area of 5,530 mi**2. The reservoir was originally built for flood control, irrigation and sedimentation. However, acute shortages of water for irrigation in recent years have raised questions concerning future policies for the reservoir management. This paper evaluates the long-term performance of the Cedar Bluff Reservoir under various water-use options by stochastic simulation. In particular, the risks of water shortages and the frequency distributions of the pool level are determined.
A mathematical model was developed to simulate the pipe filling process and the pipe forces based on incompressible water column theory. The method easily accomodates appropriate boundary conditions. The resulting equations are solved numerically. Comparison with an approximate method in the case of typical condensate demineralizer drain system indicates that the mathematical model results in a more realistic design of the pipe restraints.
Both a mainframe and personal computers are used by the Water Use Division of the South Florida Water Management District in the consumptive water use permitting process. Numerical and analytical drawdown models are used to project the effects of ground water withdrawals. Project data files being used to computer-generate staff summary reports, then to be included into other data bases. Water withdrawal and monitioring data submitted by permit holders is entered into computer data files for use in the analysis of water resource conditions.
An iterative procedure involving an implicit finite difference numerical scheme was implemented on an IBM personal computer for solving steady, uniform and nonuniform boundary layer flow problems in stormwater detention basins. A flat plate configuration was accepted for the basin bottom, approximating uniform sediment deposition. The numerical scheme is efficient and converges rapidly to accurate results.
The experimental study was intended to investigate characteristics of the cross flow turbine based to the three models designed on the same runner diameter with different runner length of each. The Flow rates were measured by magnetic flow meter, the forces were detected by using spring balance and turbine speeds were detected by tachometer. The performance characteristics are shown by the relation of Power and efficiency versus jet entry arc, as well as the relation of Power and efficiency versus ratio between diameter and width of runner. The study indicated that the efficiency of the models were slightly difference, the highest efficiency indicated by the turbine with the ratio between length of runner and the diameter of the runner was 2; It was corresponding to the 75 degree entry arc.
Area 3A in the Tenoroc State Reserve near Lakeland, Florida is an inactive and abandoned phosphatic waste clay area. The disposal area has been inactive for several years and the clays have been consolidated under self-weight since deposition began. Specific measures had to be designed and installed to control turbid discharges from the site during the earthmoving and land clearing phases of reclamation. To prevent turbid discharges beyond the project area into state waters, a system utilizing chemical flocculants was proposed and designed. Prior to construction, laboratory testing with high molecular weight polymers was conducted to evaluate their effectiveness with the site soils.
