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1950-1979

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https://hdl.handle.net/10217/100535

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Browsing 1950-1979 by Author "Albertson, Maurice L., committee member"

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    Conjunctive use of surface water and groundwater with different salinities in the Indus Basin of Pakistan
    (Colorado State University. Libraries, 1974-06) Wu, Fang-Hong, author; Longenbaugh, Robert A., advisor; Kemper, W. Doral, committee member; Albertson, Maurice L., committee member; Labadie, John, committee member; Richardson, Everett V., committee member
    A mathematical model for optimal conjunctive use of sur face water and groundwater is developed to determine canal and tubewell installed capacities in three different groundwater salinity zones. The objective is to minimize the total capital investment, and the operational and maintenance costs, for the system to satisfy a given irrigation water requirement. The Lower Jhelum canal command, one of many similar hydrologic areas in the Indus Basin, is selected as the area for testing the mathematical model. The system is decomposed into a two-level approach for easier problem solving by separating the design variables and the operational variables. In the design level, the flexible tolerance algorithm is used to search iteratively for the optimal design alternative. Each time a design alternative is chosen, the design variables are considered as fixed parameters and a sequential decision process is used to determine the optimal operational decisions within a time interval. During each subperiod, direct river diversion will be the most feasible solution whenever the available river flow can satisfy the wat er requirement without causing water logging in the three areas and lateral salt water movement to the relatively fresh water area. Otherwise linear programming is adopted to allocate the available river flow and usable groundwater subject to constraints of water availability, canal capacity, water logging, salt water coning, lateral salt water movement and the water requirement. The study shows that through conjunctive use of groundwater and surface water, an irrigation system can be designed as an “on demand" system providing sufficient water to meet a cropping intensity of at least 150 percent without waterlogging and salt water contamination. An optimal conjunctive use policy would transfer available surface water to the more saline groundwater areas, and the existing canal capacity would have to be expanded. Generally groundwater in each of the three different areas would be pumped for their own use except the amount which must be exported for salt balance and control of the water table. The mathematical model is applicable to other canal commanded areas in the Indus Basin, Pakistan and other areas with similar groundwater salinity problems.
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    Terminal fall velocity of particles of irregular shapes as affected by surface area
    (Colorado State University. Libraries, 1964) Alger, George R., author; Simons, D. B., advisor; Albertson, Maurice L., committee member; Karaki, Susumu, committee member; Fead, John W. N., committee member; Johnson, Roberta F., committee member
    The objective of this research is to study the effect of surface area on terminal fall velocity of particles and objects of irregular shapes. An auxiliary study was also made in a qualitative manner on the effect of various concentrations of neutrally buoyant fine material on the fall velocity of spheres. The results of this auxiliary study are given in Appendix (B). It is expected that these investigations will lead to further research in areas related to these topics. Various shapes of gravel-sized particles were studied. The terminal fall velocities were obtained by repeatedly dropping the same particles in fluids with different viscosities. A photographic technique was used to determine these terminal velocities. A new shape parameter was developed and the variation of drag coefficient with Reynolds number using this new parameter is given. This Cd versus Re relation leads to the possibility of a model law for the irregular shapes with the new shape parameter as the third variable. A limited verification is given for several selected machined shapes and for ordinary concrete test cylinders. The model verification was accomplished by dropping larger scale particles in water and measuring terminal fall velocity using a specially constructed large scale speedometer. Plastic (Vestyron) particles were used to form a neutrally buoyant suspension in salt water. A small plastic sphere was dropped through various concentrations of this suspension and the fall velocity was determined with a stop watch. The results indicate the nee d to study the electrochemical properties of the suspended fine material as they appear to affect the fall velocity of the larger particle. The writer believes from the results obtained that the consideration of the Zeta potential of the fine material would ultimately lead to a better description of the apparent viscosity effects when used in conjunction with existing theories.