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Thesis (Ph. D.)--Virginia Polytechnic Institute and State University, 1988. / Vita. Abstract. Includes bibliographical references (leaves 225-227). Also available via the Internet.

Thesis (Professional Degree)--University of Missouri, School of Mines and Metallurgy, 1905. / Typescript. Illustrated by author. Raphael C. Alexander determined to be Raphael Curier Alexander from "Thirty-Third Annual Catalogue of the School of Mines and Metallurgy". The entire thesis text is included in file. Title from title screen of thesis/dissertation PDF file (viewed November 14, 2008)

Thesis (M.A.)--University of Wyoming, 2009. / Title from PDF title page (viewed on July 23, 2010). Includes bibliographical references (p. 124-131).

M.Ing. / This thesis considers in detail the applicability to hydro power systems of the theories of steady and unsteady flow in pipelines. In doing so.it highlights some of the shortcomings of these theories. An attempt is made by way of experimentation on a high pressure pipeline, to model some of the conditions which could occur in a full size future hydro power system. These experiments provide some quantitative data about the performance of some typical hydro power components such as pipes, orifices and valves, under steady and unsteady conditions. A computer program is included which was used to provide theoretical data to compare with the experimental results. The program was found to be limited in its capacity to provide accurate simulation of the experimental pipeline, but this was thought to be due to the pipeline not correctly modelling a hydro power system. Conclusions presented in this thesis will be of assistance to designers of future hydro power systems and to researchers continuing this work.

This thesis offers a review and an analysis of all except the less important advances of the previously developed methods and equations for optimizing the operation of an electric system of m thermal and n hydro plants. In this analysis both short-range (twenty-four hours, seven days) and long-range (one year) periods are involved. The primary objective of this thesis is to derive, using the Calculus of Variations, general differential equations for short-range optimization of combined hydro-thermal systems. The basic criterion for choosing to solve the short-range instead of the long-term problem lies in the theory of forecasting in general, the theory of forecasting of stream flows in particular, and is based on the aforementioned analysis. Tests for establishing the fact that the above general equations actually produce the desired minimum cost of operation are given in the form of three other necessary conditions and three sufficient conditions. These conditions are known in this branch of mathematics as the analogue of Legendre's condition, the Weierstrass’ analogue of the Jacobi's condition and the Weierstrass' E-function condition for a minimum. A well-known example is worked out using these conditions. In addition to the above, this thesis also proves that all previously developed methods and equations for short-term optimization are essentially equivalent, and that these formulas are merely simplified forms of the general equations developed in this treatise. / Applied Science, Faculty of / Electrical and Computer Engineering, Department of / Graduate

Hydroelectric power has traditionally been the object of much publicity in the Soviet Union, yet few facts are available regarding the significance of hydro to the electricity industry on a national, and especially on a regional, basis. This thesis seeks to clarify the situation in determining the significance of Soviet hydro potential as well as existing hydro capacity on both national and regional levels. In so doing a system of regions based on power networks has been used and for these regions total installed generating capacities have been calculated so as to provide a basis for quantitative ranking. This study is not concerned simply with the generation of electricity, but with estimating absolute size and type of regional installed capacity and generation, together with the heretofore neglected aspect of consumption. A different approach to evaluating the importance of consumers of electricity is advocated, one in which load factor plays an important role and required KW capacity to meet a particular demand constitutes the prime criterion. The result has been to emphasize the spatial variations in complementary aspects of the Soviet electricity industry. It was found that the concepts most frequently used in assessing Soviet hydro potential have certain limitations, the most important being a neglect of relative distribution. By considering the distribution of remaining prospective dam sites in terms of "economically accessibility," it has been possible to reduce the figure for Soviet hydro potential by almost one-half. While it has been shown that there has been a movement eastward and therefore greater correlation between hydro capacity and hydro potential at present, including hydro capacity currently being installed, almost a third of the "economically accessible" hydro potential is now utilized. For many years there has been concern over meeting system peak load demand economically and in this context hydro capacity in many regions has assumed the function of meeting peak load demand, especially during the winter months. The Central Siberian region has not as yet realized the full benefit of the large scale projects, both hydro and thermal, thus far undertaken and at present is not characterized by low cost electricity. A decreasing average cost can be expected during the next few years. While traditionally viewed as a source region of electricity it has been determined that a possible export of 15-20 percent of total regional generation would have only a limited impact if exported to European Russia. It can be expected that this region will prove to be attractive in the location of electricity intensive industry. It is the concensus here also that large scale hydro construction will continue, but at a slower pace. The demand for electricity in Central Siberia is not yet characterized by any particular industry or sector. In the future aluminum production will constitute an important share of total demand for electricity in this region. The one feature common to the four regions of European Russia is a dependence to a greater or lesser degree on external sources of energy for the generation of electricity. While emphasis has been placed on the utilization of local energy resources, insofar as hydro is concerned, little can be expected as over 80 percent of potential has now been utilized. To date the Urals and Center-Volga have experienced the most serious power shortages, due primarily to the high degree of industrialization and heavy concentration of urban population respectively. The South in contrast does not appear to be in the same situation, the result both of its broader energy resource base and a more diversified demand. The Northwest region while scheduled to be interconnected with the Unified European Power Network, lacks any distinguishing feature in its electricity industry and will remain of peripheral importance. Within what have been referred to as the Peripheral Regions there exists considerable "economically accessible" hydro potential. However, much of this is likely to remain undeveloped for many years to come, especially in the Far East. In the Caucasus and Central Asia, while hydro has traditionally provided the bulk of electricity, in recent years gas-fired thermal stations have made striking inroads. In the Caucasus limited gas reserves will of necessity force the region to look to external sources if this trend is to continue. This is not a problem in Central Asia where there exists extensive gas reserves. Of the remaining regions, Northeast Kazakhstan and Murmansk, only the former is scheduled to assume significance on the national level. / Arts, Faculty of / Geography, Department of / Graduate

This thesis examines the influence of different degrees of serial correlation in the streamflow records on optimal operation of a hydroelectric reservoir. This thesis also investigates the practical aspects of choosing different decision variables, considering effects on ease of implementation, total benefit, and actual use for real-time operations. Stochastic dynamic programming was used to optimize the long-term operation of a hydroelectric project with a single reservoir. Reservoir inflows were analyzed using monthly flow record for 58 years with the assumption that monthly inflows are either perfectly correlated, uncorrelated, or partially correlated. Reservoir level change and powerhouse discharge were considered as alternative decision variables for each of the three cases of inflow serial correlation. The optimization results were then examined and compared to determine the significance of the choice of decision variables and to explore the effects of inflow serial correlation on practical operating decisions which might be based on the results of the optimization. It was found that (1) Case 2 in which inflows were assumed perfectly correlated and Case 3 with partially correlated inflows produce, respectively, highest and lowest total expected return, (2) the difference in total expected return between cases depends largely upon the physical characteristics of the system, (3) the reservoir level change decision case produces more conservative results than the discharge decision case, (4) the results from the reservoir level change decision are easier to use for realtime operation than those from the discharge decision case, (5) different results will be produced with different choice of decision variables. / Applied Science, Faculty of / Civil Engineering, Department of / Graduate

The inspection of deep and long, water-filled tunnels at pumped storage hydroelectric stations has posed a challenge to the electric utility industry. Virginia Power and its partner, Allegheny Power System, faced this challenge at its Bath County Pumped Storage Station in western Virginia. <p>Bath County is the largest station of its kind in the world with a combined generating capacity of 2100 megawatts. The station consists of six pump/turbines and three large tunnels, each 28.5 feet in diameter and approximately two miles long, which link the upper and lower reservoirs. <p>After reviewing the alternatives of using divers, manned submersibles and dewatering of the tunnels, the owners decided to use a submersible remotely operated vehicle (ROV) for the inspection task. A study was performed which determined that the owners could save approximately $677,000 by performing the work in-house versus hiring a specialty contractor. <p>An ROV system was developed and equipped specifically for tunnel inspection work. Three video cameras, a stereo photo camera, dye release system, dual head sonar, and a 7000 foot umbilical provided the inspection capabilities. <p>The overall condition of the tunnels was very good, particularly in the upper and lower horizontal sections. The vertical flow shaft of the tunnel had two predominant longitudinal cracks with the east wall crack showing evidence of water egress. <p>The ROV system proved to be a very safe, economical, and reliable means of conducting inspections of this type. The vehicle successfully completed the 6100 foot excursion at a maximum depth of 1350 feet, representing the longest tunnel excursion performed to date. It is probable that inspections of this type will become the norm at hydroelectric stations as well as other facilities with similar tunnel systems requiring inspection. <p>This report will describe the background of the project, discuss the evaluation of inspection alternatives. and provide a complete description of the HYDROVER system and its development. A brief discussion of the results of the inspection of the first of the three tunnels will be presented. Although portions of the remaining two tunnels have now been inspected, these results are not within the scope of this paper. <p>Following the discussion of the system development and inspection results, conclusions will be presented regarding the viability and future role of this advanced underwater technology. / Master of Engineering