St. Anthony Falls Laboratory
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The St. Anthony Falls Laboratory (SAFL) was designed and built in the 1930s under the direction of Lorenz G. Straub with funds from the Works Progress Administration and the University of Minnesota. The building was dedicated on November 17, 1938 and the Laboratory began its work in hydraulic and river engineering research as part of the Department of Civil Engineering.
Today SAFL is an interdisciplinary fluid mechanics research and research training facility of the College of Science and Engineering. Research focuses on environmental, energy, and health challenges.
Current information about SAFL and its programs is at http://www.safl.umn.edu.
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Item 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.Item Hydraulic Model Studies for Chippewa River Reservoir Dam(St. Anthony Falls Laboratory, 1947-09) DeLapp, Warren W.The following is a report of tests made on a 1:24 scale model of the Chippewa Reservoir Dam, a property of the Northern States Power Company, located in the headwaters of the Chippewa River, Wisconsin.Item Investigation of Flow Through Standard and Experimental Grate Inlets for Street Gutters(St. Anthony Falls Laboratory, 1947-10) Larson, Curtis L.This report presents the results of an investigation of the flow of water and entrained debris through standard and experimental gutter inlets of the grate type. The investigation was requested by the Minnesota Highway Department in connection with the proposed construction of a length of highway at 6 per cent grade. Under the sponsorship of the Highway Department, the experiments were conducted at the St. Anthony Falls Hydraulic Laboratory of the University of Minnesota.Item The Nature of Flow in an Elbow(St. Anthony Falls Laboratory, 1947-12) Silberman, EdwardThe available information on fluid flow diversion is limited largely to the experimental value 6 of the bend loss coefficient, and the variation of this coefficient with such factors as radius ratio, aspect ratio, and deflection angle. Some analytical work has also been done in the laminar flow region and on two-dimensional bends of continued curvature. There has been a decided need, however, for a general theory explaining the flow phenomenon and the mechanism of energy loss in a three-dimensional bend of fixed deflection angle. This report describes experiments which were directed toward obtaining such information.Item Hydraulic Model Studies for the Holcombe Dam(St. Anthony Falls Hydraulic Laboratory, 1948-08) Anderson, Sigurd H.Hydraulic model studies were made on a 1:43.2 model of the spillway section of the proposed Holcombe Dam to be constructed by the Northern States Power Company on the Chippewa River at Holcombe, Wisconsin. The spillway was designed by the Pioneer Service and Engineering Company of Chicago, Illinois.Item Model Experiments for the Design of a Sixty Inch Water Tunnel Part VI(St. Anthony Falls Hydraulic Laboratory, 1948-09) Holdhusen, James S.The purpose of the recirculating pump in the water tunnel is to supply energy efficiently to the circulating stream so that the resistance of the circuit may be overcome. In most pump installations this is practically the only requirement for which the pump is designed, but in the water tunnel installation the secondary characteristics of the pump must be carefully controlled. Some of these secondary characteristics which would seriously affect the usability of the water tunnel are pulsation, cavitation, noise level, stream rotation, and outflow velocity maldistribution. This study will not discuss the pump design since that will be the responsibility of the eventual manufacturer. Rather, it will furnish fundamental information based on the tests of the model water tunnel which the manufacturer should know in order to design the pump properly.Item Model Experiments for the Design of a Sixty Inch Water Tunnel(St. Anthony Falls Hydraulic Laboratory, 1948-09) Purdy, Harry D.The report describes apparatus designs which were largely evolved by John F. Ripken, Associate Professor of Hydraulics; James S. Holdhusen, Research Fellow, was project leader and developed test procedures. Frank Dressel was in charge of the physical construction of the equipment.Item Selected Translatons from Transactions of the Institue of hydraulic Machines of the Karlsruhe Technical University(St. Anthony Falls Laboratory, 1948-09) Pilch, MeirThe special installations for investigation of the details of the flow patterns in the machines are described separately in each article. Only the model test arrangement for turbines and pumps shall be described here.Item Model Experiments for the Design of a Sixty Inch Water Tunnel Part II(St. Anthony Falls Hydraulic Laboratory, 1948-09) Ripken, John F.; Holdhusen, James S.A recirculating type of water tunnel is designed to produce a steady stream of fluid having uniform velocity and pressure in the test section. However, the tendency of the recirculating system is to produce variations in velocity from point to point across a section of flow due to growth of the boundary layer. Superimposed on this variation of velocity in space is a variation of velocity in time caused by turbulence in the stream. The necessity of diverting the stream through 360 degrees and of adding energy by means of a rotary impeller introduces the possibility of superposition of steady large-scale turbulence on the stream, but correct design of elbows and pump can effectively eliminate this source of velocity variation.Item Model Experiments for the Design of a Sixty Inch Water Tunnel Par IV(St. Anthony Falls Hydraulic Laboratory, 1948-09) Holdhusen, James S.A study of the main diffuser (the diffuser following the test section) for a water tunnel was made at the St. Anthony Falls Hydraulic Laboratory as part of the research program for the design of the proposed 60-in. water tunnel of the David Taylor Model Basin, Bureau of Ships, Department of the Navy. The diffuser was designed on the basis of previous investigations of other experimenters, and the testing program was conducted to determine the action of the diffuser as it will be affected by the conditions of inflow and outflow in the recirculating system of the prototype water tunnel. It was determined that the diffuser will operate satisfactorily as to energy loss but that there will be slight maldistribution of velocity at the downstream end. It was decided, however, that this maldistribution will not be sufficiently detrimental to operation of the water tunnel to warrant making the diffuser longer and of a smaller angle of divergence.Item Model Experiments for the Design of a Sixty Inch Water Tunnel Par III(St. Anthony Falls Hydraulic Laboratory, 1948-09) Holdhusen, James S.A study of the test section for a water tunnel was made at the St. Anthony Falls Hydraulic Laboratory as part of the research program for the design of the proposed 6o-in. water tunnel of the David Taylor Model Basin, Bureau of Ships, Department of the Navy. It was determined that the variation in velocity across the test stream would be less than one per cent everywhere except in the boundary layer, which would have a maximum thickness of ten per cent of the diameter of the test section. The pressure gradient and energy loss in the test section were computed assuming the test section boundary layer to be analogous to that of a plate in a uniform stream. The critical cavitation area in the tunnel circuit was found to be at the transition from the test section to the diffuser, and the corresponding critical cavitation indexes were calculated for several points in the test section.Item Model Experiments for the Design of a Sixty Inch Water Tunnel Part V(St. Anthony Falls Hydraulic Laboratory, 1948-09) Holdhusen, James S.; Lamb, Owen P.A study of vaned elbows was made at the St. Anthony Falls Hydraulic Laboratory as part of the research program for the design of the proposed 60-in. water tunnel of the David Taylor Model Basin, Bureau of Ships, Department of the Navy. The shape, size, and spacing of the vanes to be used in the elbows were determined from the work of previous investigators, and model studies of the vane cascade were performed at the Laboratory as part of a broad research program in fluid flow diversion. Additional model studies of the assembled elbow were performed on a 1:10 scale model of the 6o-in. tunnel. From the model studies on the vane cascade, the optimum angular setting of the vanes was obtained, as well as data regarding pressure distribution and energy loss. The validity of the application of model results to a prototype was examined in the additional studies on the elbows in the model water tunnel. On the basis of this study, a cascade of vanes of the proportions shown in Fig. 44 of this report is recommended for use in the prototype tunnel. The vanes are to be used at a spacing-chord ratio of 0.48 and a stagger angle of 99 to 101 degrees. The miter line is to cross each vane at about 37 1/2 per cent of the chord from the leading edge. Structural analysis of these vanes indicates that they may be of either solid or hollow cross section without detrimental effects on stresses, deflections, or vibrations. The studies also indicate that the vaned elbows in the prototype tunnel will be free from cavitation.Item Hydraulics of Flow in Culverts(St. Anthony Falls Laboratory, 1948-10) Larson, Curtis L.; Morris, Henry M.With modern tendencies and developments in highway design, construction of culverts for cross drainage of storm runoff represents n ever-increasing item of expense. As wider highways have been built, culvert lengths have been correspondingly increased. In addition to increased lane width requirements, multiple-lane super-highways are becoming more and more prevalent. Furthermore, allowable curvatures and grades have been reduced, both of which tend to increase culvert lengths by increasing fill heights. For every increase of one foot in fill height, culverts are lengthened several feet.Item Investigation of Airfield Drainage Arctic and Subarctic Regions: Part I: Field Reconnaissance and Analysis(St. Anthony Falls Hydraulic Laboratory, 1949-04) Johnson, Loyal A.This report is intended to summarize the outcome of a field investigation of selected sites in Alaska, and subsequent studies which were made at the St. Anthony Falls Hydraulic Laboratory. The project was carried forward under the general supervision of Dr. Lorenz G. Straub, director of the Laboratory. Loyal A. Johnson, research associate, made the field investigations, carried out the library research, and prepared the report. Maps, diagrams, and other drawings were made with the aid of Laboratory draftsmen and student assistants. Professor R. B. Whittington offered many timely suggestions and carried out the mathematics, the results of which are included in Part VII. The entire content of the report was reviewed by Alvin G. Anderson and Henry M. Morris, both Laboratory staff members. The paper was edited and prepared for publication by Lois E. Fosburgh.Item Investigation of Airfield Drainage Arctic and Subarctic Regions Part II(St. Anthony Falls Hydraulic Laboratory, 1949-04) Pilch, MeirMany structures erected in zones of aggressive ground water are periodically flooded by the ground water penetrating through the floors and the walls; this occurrence creates complications and occasionally makes it impossible to use the structure. Frequently structures are erected in regions having a high groundwater table. To assure normal and uninterrupted use of buildings existing under these conditions, it is necessary to give particular consideration to problems pertaining to special waterproofing measures. It should be noted that the quality of the waterproofing depends not only on the kind and quality of the materials used but also, to a great extent, upon the quality of the workmanship.Item Fluid Flow Diversion by Guide Vanes in Miter Bends(St. Anthony Falls Hydraulic Laboratory, 1949-04) Silberman, EdwardA search of existing literature revealed several papers dealing with experimental investigations of specific vaned turns and others which approached the problem analytically. None of these, however, outlined general criteria for design and performance of guide vane cascades in miter bends which would be applicable to new installations. Such criteria have been established in this paper.Item Preliminary Flow Tests on a Model Culvert(St. Anthony Falls Hydraulic Laboratory, 1949-05) Morris, Henry M.A number of tests were made with the model culvert flowing full and with both inlet and outlet submerged. The purpose of this series was to determine the straight barrel friction losses for various discharges and the influence thereon of the Reynolds number, the presence or absence of entrance rounding, and the distance from inlet. Entrance losses were also determined.Item Air Entrainment in Flowing Water(St. Anthony Falls Hydraulic Laboratory, 1949-08) Lamb, Owen P.The physical entrainment of a gas by a liquid and the flow of gas-liquid mixtures are phenomena commonly encountered in engineering practice, but avoided or arbitrarily compensated for in theoretical considerations and in design analysis. The progress toward a satisfactory explanation of these phenomena has been hampered by a lack of accurate experimental observations of entrained flows and by the complexity of the theoretical analysis when certain of the physical forces can no longer be neglected.Item Air Bubble Resorption(St. Anthony Falls Hydraulic Laboratory, 1949-08) Silberman, EdwardThis paper describes an analysis and experiment directed at determining the laws governing the rate of solution of a gas bubble in turbulent liquid. The object of the research was to determine methods for resorbing air bubbles which have been freed from the water in a water tunnel. A basic equation governing the resorption process which has been developed and partially verified in the work is presented as Eq. (13) in the text. Useful approximate forms of this equation are given as Eqs. (14b) and (14d) in the text. The basic equation has led to several suggested methods for accomplishing resorption in water tunnel. These include: (1) a resorber method already developed at the California Institute of Technology[1]*; (2) a method in which air in solution in water would be completely replaced in the closed water tunnel circuit by another gas such as carbon dioxide; and (3) a method in which a lengthened return circuit would be combined with a fin-scale turbulence, introduced in the return circuit to hasten air bubble resorption while keeping the bubble from rising. The time required for resorption by any of these methods may be estimated from the basic equation.Item Hydraulic Model Studies for Whiting Field Naval Air Station, Part I - Part IV(St. Anthony Falls Hydraulic Laboratory, 1950-01) Blaisdell, Fred W.; Donnelly, Charles A.The purpose of this report is to discuss tests made on a straight drop spillway and its energy dissipator and to present a design of energy dissipator for use in B Ditch at the Whiting Field Naval Air Station, Milton, Florida. The particular structure on which tests were made is designated B-6, but similar designs will be used for Structures F-5, G-2, L-2, S-l, and Y-6. The tests were requested by Mr. Moratz on September 27, 1948, the request amended on October 6, 1948, and the study completed on October 14, 1948.