Browsing by Author "Anderson, Alvin G."

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Addendum To Final Memorandum Of July 1963: Calibration Of Spillway With Low Crest Blocks
(St. Anthony Falls Hydraulic Laboratory, 1966-01) Anderson, Alvin G.
This addendum reports the results of calibration tests on the partially completed Angat spillway. The study was based upon a memorandum by W. A. Waldorf, Harza Engineering Company, dated September 20, 1965.
Cavity Formation and Associated Drag in a Supercavitating Flow Over Wedges in a Boundary Layer
(St. Anthony Falls Hydraulic Laboratory, 1964-04) Stefan, Heinz G.; Anderson, Alvin G.
Supercavitating flow over wedges (half-wedges) attached to a solid boundary can be simulated by air injection in the wake of the wedges. Information on cavity formation behind single wedges in a boundary layer, specifically, cavity length, air demand, and pressure distribution inside and outside the cavity as a function of wedge characteristics (height and angle), stream velocity, and blockage effect was obtained by experiment. Drag on such single artificially supercavitating wedges was measured. Experiments were carried out in a conduit of rectangular cross section with the wedges attached to the bottom. The ultimate purpose of the investigation was to examine whether a cavity generated on a flat plate has a skin friction reducing effect and how such a cavity can be generated most efficiently by a wedge without introducing important supplementary drag.
The Distribution of Air in Self-Aerated Flow in a Smooth Open Channel
(St. Anthony Falls Hydraulic Laboratory, 1955-07) Anderson, Alvin G.
The high-velocity self-aerated flow in an open channel is characterized by the appearance of "white water" caused by the entrainment of atmospheric air. The phenomenon appears to be made up of two parts. In the lower portion of the flow the entrained air is in the form of bubbles distributed through the flow. Above this region, water particles projected outward from the flow by the intense normal velocity fluctuations give rise to the highly agitated appearance of the flow.
Effect of Inlet Design on Capacity of Culverts on Steep Slopes
(St. Anthony Falls Hydraulic Laboratory, 1954-04) Straub, Lorenz G.; Anderson, Alvin G.; Bowers, Charles E.
The geometry of the inlet has a significant bearing on the relationship headwater elevation and discharge for culverts with a free outlet. The relative importance of inlet design depends upon the location of the control section. The primary purpose of the research reported here was to examine the effect of inlet design upon the head-discharge curve of a model culvert. Two types of flush inlets, selected to represent extreme conditions for flush inlets, were tested--a square-edged inlet and a well rounded inlet. For each inlet the head-discharge curve was measured and the two curves compared. The comparison indicated that for certain conditions an appreciable head-advantage was gained by using a rounded inlet. Observation and analysis of the flow characteristics indicated that this gain phenomenon occurred in the region where for the same head a square-edged inlet caused separation and inhibited full flow, while the rounded inlet promoted full flow in the culvert with a corresponding increase in discharge. In connection with measurements to establish friction factors and entrance losses in the model culvert for use in the analysis of the experimental, a few behavior curves were determined. An analysis of behavior curves is included in Appendix IV. The results obtained were compared with experimental curves and other published curves.
The Flow and Stability Characteristics of Alluvial River Channels
(St. Anthony Falls Hydraulic Laboratory, 1975-09) Anderson, Alvin G.; Parker, Gary; Wood, Addison
Alluvial rivers, insofar as they transport the material of which their channels are composed, possess the freedom to alter their geometry through the phenomena of erosion and deposition. River channels can be loosely divided into bed and bank regions, and geometry alteration phenomena can likewise be divided into bed processes and bank processes. An analysis of bank processes is dependent on a general knowledge of bed processes. Bed processes associated with wide, equilibrium rivers, in which bank processes are negligible, are examined in Chapter I of this report. An attempt is made to find the most general possible forms for sediment transport and bed resistance relationships. The forms are general enough so that existing equations can be expressed within their framework. Bank processes, and in particular bank erosion, are the subject of the remainder of the report.
Fluid Flow Diversion
(St. Anthony Falls Laboratory, 1947-08) Anderson, Alvin G.
A knowledge of the motion of a fluid as it undergoes a change in direction, and of the energy and pressure variations which accompany the directional diversion has many applications in engineering practice. The designing of duct and piping systems requires a knowledge of the pressure losses incurred in the flow of a fluid around a bend. In large installations, it may be necessary to investigate means of reducing the pressure losses in elbows from the standpoint of power requirements. In installations such as wind tunnels and water tunnels constructed for aerodynamic and hydrodynamic research, the requirements for uniform velocity distribution and parallel flow downstream from the bend are greater than pressure considerations, and a knowledge of the effects of guide vanes on flow around a corner is important. The efficiency of pumps, turbines, propellers, and fans is influenced by the relationships between curvature of the streamlines and the resulting pressures and velocities.
Hydraulic Model Studies for the Guri Hydroelectric Project Report On the Second Stage Diversion and Flow Characteristics of the Spillway
(St. Anthony Falls Laboratory, 1966-02) Anderson, Alvin G.; Charbonneau, Arthur L.
The Guri Hydroelectric Project, located on the Caroni River in Venezuela, is designed to provide power for the industrial development and river regulation for other downstream plants. The dam is a concrete gravity structure with an earth and rock-filled tie-in to the right bank. In the initial project, the crest will be at El. 220 m above sea level. In the future it is proposed to raise the crest in stages to EI. 245 m and finally to El. 266 m above sea level. The spillway located on the left abutment will consist of three converging concrete chutes with a total width at the crest of 182 m (including the piers) and with lengths varying from 175 to 225m. Intakes and penstocks are incorporated within the gravity structure and lead to the proposed turbines in the powerhouse located downstream of the concrete structure.
Hydraulic Studies of the Spillway for the Mangla Dam
(St. Anthony Falls Laboratory, 1968-02) Anderson, Alvin G.; Dahlin, Warren Q.
The Mangla spillway is an excellent example of the interdependency of hydraulic design, structural design, and economics, each of which has a bearing upon the project. This final report of the experimental program describes a long series of experiments to test different design concepts that were evolved to meet the demands of the field conditions. The initial studies dealt with the ski-jump principle, which for reasons of cost was attractive. However, because of the excessive scour of the relatively non-resistant foundation material in the neighborhood of the main embankment, this was abandoned and the research was dissipated in a stilling basin. The very high uplift forces associated with this particular application of the single stilling basin scheme led eventually to the two basin scheme, in which the pool floor of the upper stilling basin is located approximately at tailwater level to eliminate high uplift forces.
Hydraulics of Long Vertical Conduits and Associated Cavitation
(St. Anthony Falls Hydraulic Laboratory, 1971-06) Anderson, Alvin G.; Vaidyaraman, P.; Chu, C.
Experimental studies have been undertaken to examine the flow in long vertical conduits with particular reference to the design of storm water drop shafts. A distinguishing characteristic of such flow is the potential cavitation regime. Its existence depends upon the design of the structure. The cavitation regime will develop when the conduit is sufficiently long and the head sufficiently large. It can also be generated at a lower head if a control valve is installed in the supply line so that the net head can be negative. The cavitation region consists of a rather finely divided mixture of water and water vapor at a constant cavitation pressure of about -32.0 ft of water throughout the region and for all discharges. The cavitation region terminates with a shock front whose location is also a function of the discharge. The concentration of vapor, while relatively constant throughout the cavitation region, decreases with increasing discharge. If a small amount of air is introduced into the system, the cavitation region is eliminated, the pressure gradient is more uniform, and the flow consists of a uniform mixture of air and water. This report was submitted in fulfillment of Project Number 11034 FLU, Contract EPA 14-12-861, under the sponsorship of the Water Quality Office, Environmental Protection Agency.
Importance of Inlet Design on Culvert Capacity
(St. Anthony Falls Hydraulic Laboratory, 1953-01) Straub, Lorenz G.; Anderson, Alvin G.; Bowers, Charles E.
The design of a culvert inlet has a significant bearing upon the relationship of the head to the discharge of a culvert. Its relative importance hinges upon the type of flow occurring in the culvert, which in turn is governed by the location of the control section. For part-full flow the control may be either at the inlet or the outlet depending on whether the slope is hydraulically steep or mild. In the case of short culverts, control may be at the inlet even for horizontal or mild slopes. For full flow, barrel friction provides the control. The head-discharge curves of culverts having square-edge inlets have been compared with those for culverts having rounded inlets to illustrate the conditions for which a head-advantage may be obtained by using a rounded inlet. These comparisons have been made for three categories of culvert flow: long culverts on steep slopes, long culverts on mild slopes, and short culverts. Dimensionless head-discharge curves have been plotted for culvert flow in each category. For culverts on steep slopes, experimental data have been compared with the computed values and, since the agreement was reasonably good, serve as a basis for the analysis of flow in culverts operating under conditions other than those for which the tests were made. The greatest head-advantage for a particular discharge of the rounded inlet over that of a square-edge inlet was found for those cases in which the control section was located at the inlet. These were long culverts on steep slopes or short culverts where the length was negligible. for long culverts on mild slopes, the head-advantage was far less pronounced.
Model Studies - Foothill Feeder Project Metropolitan Water District Of Southern California Part I. Regular Gate Structure
(St. Anthony Falls Laboratory, 1967-02) Anderson, Alvin G.; Anderson, David J; Kuha, Roy M.
The foothill Feeder Project of the Metropolitan Water District of Southern California incorporates a long tunnel that will be part of the system which will supply water to a large area in Southern California including metropolitan Los Angeles. In this system head control devices are needed to regulate the discharge through the tunnels and the appurtenant structures and for this purpose gated structures open to the atmosphere were chosen which also provided an access for machinery needed for the tunnel maintenance. The gate structures, circular in plan, with the necessary emergency overflow weirs were made large enough so that the machinery access into the tunnel for maintenance could be incorporated in the structure. The circular plan also provided certain structural advantages. The research described in this report was carried out to study in detail the hydraulic characteristics of these gated structures for a wide variety of possible flow conditions.
Model Studies - Foothill Feeder Project Metropolitan Water District Of Southern California Part II. Big Tujunga Gate And Spillway Structure
(St. Anthony Falls Hydraulic Laboratory, 1968-02) Anderson, Alvin G.; Anderson, David J.
The Foothill Feeder Project of the Metropolitan Water District of Southern California incorporates a long tunnel that will be part of the system which will supply water to a large area in Southern California. In this system head control devices are needed to regulate the discharge through the tunnels and the appurtenant structures, and for this purpose gated structures open to the atmosphere were chosen. The gate structures, circular in plan with the necessary emergency overflow weirs, were made large enough so that machinery access into the tunnel for maintenance could be incorporated in the structure. The circular plan also provided certain structural advantages. The research described in this report was carried out to study in detail the hydraulic characteristics for a wide variety of flow conditions for one of these structures, the Big Tujunga Gate and Spillway Structure.
Model Studies - Foothill Feeder Project Metropolitan Water District Of Southern California Part III. Morris Reservoir Turnout Structure
(St. Anthony Falls Hydraulic Laboratory, 1968-08) Anderson, Alvin G.; Anderson, David J.
The Foothill Feeder Project of the Metropolitan Water District of Southern - California incorporates a long tunnel through which water will be supplied to a large area in southern California. In this system head control devices are needed to regulate the discharge through the tunnels and the appurtenant structures. For this purpose gated control structures open to the atmosphere were chosen. The gate structures were circular in plan and fitted with gates for flow control. The research described in this report was carried out to study in detail the hydraulic characteristics for a wide variety of flow conditions for one of these structures, the Morris Reservoir Turnout Structure.
Model Studies - Lawrence Avenue Sewer System, City of Chicago
(St. Anthony Falls Hydraulic Laboratory, 1968-10) Anderson, Alvin G.; Dahlin, Warren Q.
The Lawrence Avenue Sewer System will incorporate a large deep tunnel for temporary storage of the surface runoff that will be fed to it by a series of drop shafts placed at intervals along the axis of the tunnel. Each drop shaft will be designed to handle a variable discharge, the peak value of which will be different for each. As the volume of runoff increases, the tailwater elevation may change from zero to a maximum which is governed by overflow facilities. The objectives of the research described in this report are (a) to investigate the nature of the flow in the drop shafts, suggest an optimum design, and describe the flow patterns in the final design; and (b) to examine the surges in the overall system when it is subjected to discharges of various magnitudes and in various sequences.
Model Studies of Dropshafts for the Chicago Underflow Plan Dry Weather Flow Dropshaft - Helix
(St. Anthony Falls Hydraulic Laboratory, 1974-06) Anderson, Alvin G.; Dahlin, Warren
The city of Chicago plans to construct a large number of dropshafts which will connect various parts of the existing surface sewer system to large underground storage tunnels. The St. Anthony Falls Hydraulic Laboratory has made model studies of various dropshafts proposed for use in the comprehensive plan. A particular dropshaft may be in use continuously (dry weather flow dropshaft) or during storms only (storm water dropshaft), or it may operate as a combination of the two. The mode of operation will have a considerable influence on the design for each type. The dropshafts will also vary in size depending on the discharge for the particular location. The function of a dropshaft is to convey the flow from the surface to the underground tunnels, which in some cases are over 200 ft beneath the surface. At the bottom of the dropshaft is a sump which has to withstand the impact forces of the falling water, separate the air from the water to prevent the air from entering the tunnels and return it to the surface, and convey the water to the tunnel at a reduced velocity. Various designs of dry weather flow dropshafts have been developed for study. One interesting variation was the incorporation of a helixin the dropshaft to convey the water downward and thus reduce the impact pressures and eroding forces in the sump; at the same time, for high tailwater elevations the head loss through the system was expeoted to be large and hence detrimental to its use. Because there are locations where this type of installation could be considered, De Leuw, Cather and Company initiated a project to study the flow in the helix in a dry weather flow dropshaft. Observations have been made on fluctuating and static pressures, air removal in the sump, and overall hydraulic characteristics of the structure.
Model Studies of Dropshafts for the Tunnel and Reservoir Plan
(St. Anthony Falls Hydraulic Laboratory, 1975-01) Anderson, Alvin G.; Dahlin, Warren
This report describes the model studies carried out at the St. Anthony Falls Laboratory of the diversion structures and dropshafts to be incorporated into the Chicago Tunnel Reservoir Plan. The diversion structures will divert runoff from existing conduits at the surface to dropshafts used to transport the runoff down to deep tunnels which serve as temporary reservoirs. The model studies involved the construction and testing of two diversion structures, four vertical dry weather flow dropshafts, two sloping dry weather flow dropshafts, and three vertical storm water flow dropshafts. Also during the test program, various modifications were made on these basic models. The purpose of the model studies was to assist in the development of effective and practical diversion structures and dropshafts and to study their hydraulic operating characteristics for various flow conditions. Numerous modifications were made, with limited documentation of each, to develop an optimum design. When an optimum design had evolved, more detailed observations were made during which static and fluctuating pressures were recorded and black-and-white photos, colored slides, and colored movies were taken. Photographic documentation proved to be an excellent method of recording the overall hydraulic characteristics of the structures and the air entrainment and escape mechanisms.
Model Studies-Foothill Feeder Project, Metropolitan Water District of Southern California, Part IV. San Dimas Reservoir Turnout Structure
(St. Anthony Falls Hydraulic Laboratory, 1968-08) Anderson, Alvin G.; Anderson, David J.
The Foothill Feeder Project of the Metropolitan Water District of Southern California consists of a large tunnel which incorporates various types of head control structures as well as other appurtenant structures. Each structure was designed to serve a prescribed function at a particular location. Since the functions were rather similar in nature, that is, to provide a differential head through the structure, the designs were of necessity also somewhat similar. This is particularly true of the San Dimas Reservoir Turnout Structure and the Morris Reservoir Turnout Structure. Detailed experiments were carried out with regard to the operation of the Morris Reservoir Turnout Structure so that some rough projections could be made as to the operation of the San Dimas Structure based upon these experimental results. It should be quite clear, however, that a detailed knowledge of the operating characteristics of the San Dimas Reservoir Turnout Structure can only be obtained by a model study an which all of the geometrical details are incorporated into the model and which is operated in accordance with the proposed operating scheme of the prototype.
Model Study of the Spillway for the Nader Shah Project Marun River development Khuzestan Water and Power Authority Ministry of Water and Power - Government of Iran
(St. Anthony Falls Hydraulic Laboratory, 1973-03) Anderson, Alvin G.; Dahlin, Warren
A model of the spillway for the Nader Shah Projeot, a key element of the Marun River Development under the direction of the Khuzestan Water and Power Authority of the Government of Iran, was constructed. at a soale of 1:78.7 and tested at the St. Anthony Falls Hydraulic Laboratory of the University of Minnesota. The purpose of the model studies was to observe the nature of the flow in the approach, the spillway, and the tailrace and to provide data for the structural design. Initial observations were made of the flow characteristics in the tailrace for bucket exit angles of 10°, 20°, 30°, and 40°. Considering the energy dissipation and the velocities along the left bank of the tailrace, at the bucket, and by the toe of the dam, the bucket with a 40° exit angle was judged to be the optimum design. All further tests were made on the spillway with a 40° exit bucket. Approach flow conditions, spillway ratings, water surface profiles, both static and fluctuating pressures through the spillway, and erosion in the tailrace were observed. In addition to the data presented on the charts in this report, a photographic record in the form of still photos and color motion pictures was kept during the test program. A color-sound motion picture was produced covering the model studies.
Model Study of the Spillway of the Reza Shah Kabir Project Khuzestan Water and Power Authority Ministry of Water and Power - Government of Iran
(St. Anthony Falls Hydraulic Laboratory, 1969-05) Foerster, K. E.; Anderson, Alvin G.
A model of the spillway for the Reza Shah Kabir Project of the Khuzestan Water and Power Authority of the Government of Iran on the Karun River was constructed at a scale of 1:78.7 and tested at the St. Anthony Falls Hydraulic Laboratory of the University of Minnesota. The purpose of the test was to examine the nature of the flow in the spillway and tailrace and to provide data for the structural design.
Percolation Studies For The St. Louis River Storage Dam
(St. Anthony Falls Hydraulic Laboratory, 1964-10) Anderson, Alvin G.
This report on the percolation characteristics of the foundations for a proposed dam on the St. Louis River is the consequence of discussions concerning the relative merits of several proposed foundation designs. The study was undertaken at the request of Mr. H. K. Martin of the Oglebay Norton Company to evaluate several proposed foundation designs from the point of view of safety from deleterious seepage or piping. Estimates of the uplift pressures and exit gradients based upon flow net analysis were made to establish the hydraulic stability of the structure.

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