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Articles 190411 - 190440 of 196897

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Numerical Solutions Of The Torsional Oscillations Of A Shaft-Flywheel System, Mahendrakumar Ramkrishna Patel Jan 1970

Numerical Solutions Of The Torsional Oscillations Of A Shaft-Flywheel System, Mahendrakumar Ramkrishna Patel

Masters Theses

"The application of the finite-difference technique, the Fourier transform, and the Laplace transform for the solution of a system governed by the one-dimensional wave equation is examined. A specific example consisting of a continuous shaft-flywheel system acted upon by an exciting torque applied at a specific section of the shaft is studied. The exact solution to this example is obtained using the classical method of superposition of modes, and is used as a reference to evaluate the accuracy (in terms of the rms error) and relative efficiency (based on computer time) of three approximate solution methods. A sinusoidal excitation was …

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A Three-Dimensional Mathematical Simulator Of Multiphase Systems In A Petroleum Reservoir, Leonard Koederitz Jan 1970

A Three-Dimensional Mathematical Simulator Of Multiphase Systems In A Petroleum Reservoir, Leonard Koederitz

Doctoral Dissertations

"A generalized digital analysis for calculating three phase, three dimensional flow in reservoirs is developed. The computerized mathematical model is applicable to depletion drive, gas injection, water injection, and/or aquifer drive systems with modifications specific to the simulation criterion of that type of drive and includes fluid compressibility effects, gravity drainage and capillary pressure. The simulation allows arbitrary consideration of reservoir heterogeneity, geometry, well locations and rates of production. An innovation to the alternating direction technique for linear differential equations discussed by Brian is developed and employed in order to render the method of solution applicable to non-linear differential equations. …

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An Investigation Of The Stiffness Of Shafts With Integral Disks, Richard King Riley Jan 1970

An Investigation Of The Stiffness Of Shafts With Integral Disks, Richard King Riley

Doctoral Dissertations

"The results of an investigation of the effect of an integral disk on the torsional elastic stiffness of an axisymmetric shaft are presented. Various configurations of disk diameters and widths on a shaft of specified diameter were investigated, using a finite element method of calculation verified by experimentation. The finite element method is presented for the elastic solution of a general axisymmetric body under all possible axisymmetric load conditions. The axisymmetric body is idealized as an assemblage of triangular cross-sectioned torii representing both the normal and shear properties. The elastic stiffness is used to obtain the equilibrium equations of the …

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An Investigation Of Nucleate And Film Boiling Heat Transfer From Copper Spheres, William David Hardin Jan 1970

An Investigation Of Nucleate And Film Boiling Heat Transfer From Copper Spheres, William David Hardin

Doctoral Dissertations

"This study consisted primarily of a laboratory investigation involving nucleate and film boiling heat transfer from copper spheres with saturated liquid nitrogen at atmospheric pressure. An initial study was directed towards obtaining reproducible boiling heat flux versus ΔT curves in the nucleate boiling region from surface conditions created by single and/or multiple glass bead peenings. The variables of bead size, nozzle line operating pressure, and distance a copper surface should be placed from the nozzle outlet were checked. The results indicated that a final peening of the surface with 0.0017-0.0035 inch diameter glass beads, a nozzle line pressure of approximately …

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Ionization Of Air Produced By Strong Shocks, Howard Sajon Joyner Jan 1970

Ionization Of Air Produced By Strong Shocks, Howard Sajon Joyner

Doctoral Dissertations

"This dissertation provides theoretical predictions along with experimental results for electron concentrations behind a shock as a function of Mach number over a range from 11 to 20 using a combustion driven shock tube operating in air. These theoretical predictions represent an upper bound for chemical equilibrium. The model for air was 78.0880% nitrogen, 20.949% oxygen, 0.0300% carbon dioxide, 0 .9300% argon, 0.0025%neon, and 0.0005% helium. Also the theory of a double diaphragm shock tube with corresponding pressure ratio vs. Mach number relationships is provided. A computor [sic] program using iterative techniques for a succinct presentation covering the modifications and …

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Mass Transfer From Spherical Gas Bubbles And Liquid Droplets Moving Through Power-Law Fluids In The Laminar Flow Regime, Cheng-Chun Huang Jan 1970

Mass Transfer From Spherical Gas Bubbles And Liquid Droplets Moving Through Power-Law Fluids In The Laminar Flow Regime, Cheng-Chun Huang

Doctoral Dissertations

"Continuous phase mass transfer coefficients are presented for internally circulating spheres of a Newtonian fluid traveling through a power-law type continuous phase in to so-called creeping-flow region. The Nakano and Tien stream functions allow the Sherwood number to be determined as a function of the Peclet number, power-law index, and a viscosity ratio parameter. The Hirose and Moo-Young relation is shown to be a limiting case of this solution. Mass transfer rates increase as the fluids become more pseudoplastic and/or the continuous phase consistency index increases, all other factors held constant"--Abstract, page ii.

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Some Effects Of Oh Groups On Sodium Silicate Glasses, Mokhtar Sayed Maklad Jan 1970

Some Effects Of Oh Groups On Sodium Silicate Glasses, Mokhtar Sayed Maklad

Doctoral Dissertations

"Glasses of various compositions in the Na₂O-SiO₂ system were prepared with different levels of OH concentration. Phase separation kinetics, thermal expansion, radiation induced optical absorption, and internal friction of these glasses were studied. The increase in OH content in these glasses was found to (a) enhance the rate of phase separation; (b) increase thermal expansion above the glass temperature and change the dilatometric softening temperature in a way that depends on microstructure; (c) increase the radiation induced optical absorption bands associated with positive hole centers and decrease those associated with electron trap centers; and, (d) decrease the low temperature alkali …

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The Deformation Mechanisms In Sublimed Magnesium Under Cyclic Loading, Babu Narian Thakur Jan 1970

The Deformation Mechanisms In Sublimed Magnesium Under Cyclic Loading, Babu Narian Thakur

Doctoral Dissertations

"A detailed study of the deformation processes in sublimed magnesium under reverse bending fatigue in air at room temperature has been undertaken utilizing the light, scanning and transmission electron microscopy. The Principal deformation modes are the basal slip and {10Ī2} twinning. The proportion of twinning increases markedly with the increasing stress level and the number of cycles. The evidence for cross slip is seen on the basal slip bands. The extrusions are seen not only along the basal slip lines but also along the {10Ī2} twin boundaries. In the later stages of fatigue, the extrusions chip off producing a notch …

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The Oxidation Kinetics Of Liquid Lead And Lead Alloys, Thomas Edward Weyand Jan 1970

The Oxidation Kinetics Of Liquid Lead And Lead Alloys, Thomas Edward Weyand

Doctoral Dissertations

"Liquid lead and lead-silver alloys were investigated to determine the rates and products of oxidation in pure oxygen at temperatures of 350 to 600°C. The kinetic data were determined using a Cahn electro-balance. Liquid lead was found to follow a cubic rate of oxidation between 350 and 400°C. A parabolic rate was found at temperatures above 400°C. 0.496% silver and 2.258% silver alloys followed a cubic rate of oxidation from 350 to 550°C and tended to approach a parabolic rate of oxidation above this temperature. Silver additions were found to increase the rate of oxidation as compared to the pure …

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Penetration In Granite By Shaped Charge Liners Of Various Metals, Hemendra Nath Kalia Jan 1970

Penetration In Granite By Shaped Charge Liners Of Various Metals, Hemendra Nath Kalia

Doctoral Dissertations

"The penetration in Missouri red granite by cylindrical charges with metal liners of aluminum 2011 (T-3), aluminum 7075 (T-6), yellow brass, monel, maraging steel (vascomax 250), and copper was measured. Metals having high ductility and moderate compressive strength penetrated deeper than high strength maraging steel. Aluminum required a greater standoff for optimum penetration than the other metal liners tested. Preliminary metallographic studies of the liner metals and slugs showed that the grains had elongated along the slug axis. The metals containing zinc formed very small or no slugs. The granite grains were highly fractured. The holes were discolored and coated …

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Electrode Reactions In Zinc Electrolysis, Ernest R. Cole Jan 1970

Electrode Reactions In Zinc Electrolysis, Ernest R. Cole

Doctoral Dissertations

"The effects of temperatures from 0°C to 50°C and current densities from 10 asf to 200 asf on the current efficiency in the electrolysis of pure zinc sulfate solutions (65 gpl Zn⁺⁺ - 200 gpl H₂SO₄) were determined. Pure platinum and platinum coated titanium anodes were used with an aluminum cathode. Platinum anodes were not inert at certain combinations of temperature and current density, and platinum acted as a low overvoltage impurity causing resolution of the cathode deposit. Orientation of the zinc deposits was found to vary with temperature and to have a distinct relationship to current efficiency. Preconditioning of …

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An Sem Surface Study Of Nucleate Pool Boiling Heat Transfer To Saturated Liquid Nitrogen Reduced Pressures From 0.1 To 0.9, David Virgil Porchey Jan 1970

An Sem Surface Study Of Nucleate Pool Boiling Heat Transfer To Saturated Liquid Nitrogen Reduced Pressures From 0.1 To 0.9, David Virgil Porchey

Doctoral Dissertations

"This study constituted an examination of both nucleate boiling and maximum heat flux characteristics of liquid nitrogen boiling from characterized surfaces. Several textures of gold plated copper surfaces were studied in addition to silver and silver oxide surfaces. Data were taken over a wide range of reduced pressures. All surfaces were examined using a Scanning Electron Microscope (SEM). Data and micrograph comparison revealed that both surface chemistry and surface roughness affect the nucleate boiling characteristics of liquid nitrogen. These effects are separated from each other showing that nucleate boiling is a function of both surface chemistry and topography. Surface roughness …

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A Computer Simulation Of Mine Air Shaft Thermodynamics, Ambyo Sumopandhi Mangunwidjojo Jan 1970

A Computer Simulation Of Mine Air Shaft Thermodynamics, Ambyo Sumopandhi Mangunwidjojo

Doctoral Dissertations

"Several earlier investigations have been conducted into various aspects of heat problems in underground mines. The application of general gas laws and thermodynamics in the approach of mine ventilation has been helpful in elucidating certain difficulties associated with the subject. By combining several of the techniques perfected by these researchers and applying Carrier's method of calculation for heat flow from exposed rock strata into a workable plan, a method was developed whereby it is possible to accurately and conveniently predict the quality of working environment at any point within a deep mine. The findings of this study may be of …

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Synthesis Heuristics For Large Asynchronous Sequential Circuits, Robert Judson Smith Jan 1970

Synthesis Heuristics For Large Asynchronous Sequential Circuits, Robert Judson Smith

Doctoral Dissertations

"Many well-known synthesis procedures for asynchronous sequential circuits produce minimal or near-minimal results, but are practical only for very small problems. These algorithms become unwieldy when applied to "large" circuits with, for example, three or more input variables and twenty or more internal states. New heuristic procedures are described which permit the synthesis of very large machines. Although the resulting designs are generally not minimal, the heuristics are able to produce near-minimal solutions orders of magnitude more rapidly than the minimal algorithms. A method for specifying sequential circuit behavior is presented. Input-output sequences define submachines or modules. When properly interconnected, …

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Optimizing Diesel Engine Efficiency Using The Controllability Of A Variable Ratio Hydrostatic Transmission, Gordon Wright Jan 1970

Optimizing Diesel Engine Efficiency Using The Controllability Of A Variable Ratio Hydrostatic Transmission, Gordon Wright

Doctoral Dissertations

"A linear mathematical model of a diesel engine, hydrostatic transmission, and electric dynamometer system was developed. This model was used as an aid in designing a single input controller which regulates engine speed to optimize efficiency while maintaining constant transmission output speed under changing load conditions. Compensation was necessary to stabilize the system because of positive feedback in the engine control system. The compensated system's response was compared to that which was predicted analytically. The analytical model was then extended to design the control system parameters to operate the engine and transmission in a representative vehicle"--Abstract, page ii.

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Voids In Neutron Irradiated Aluminum, Nicholas H. Packan Jan 1970

Voids In Neutron Irradiated Aluminum, Nicholas H. Packan

Doctoral Dissertations

"Void formation in high purity aluminum resulting from irradiation to fluences between 1.5 x 10¹⁹ and 1.6 x 10²² neutrons/cm² (E > 0 .1 MeV) at a temperature of 55 ± 5ºC was studied, primarily by means of transmission electron microscopy. In particular the effects of neutron fluence and flux were examined, as well as the possible influences of both preexisting and transmutation-produced impurities. A very low concentration of voids (about 10¹²/cm³) resulted from irradiation to 1.5 x 10¹⁹ neutrons/cm²; they averaged about 150 Å in diameter. Void concentrations and sizes increased with fluence, reaching values of 6 x 10¹⁴ voids/cm³ …

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Water Management Research In Arid And Sub-Humid Lands Of The Less Developed Countries: Second Annual Progress Report, Utah Water Research Laboratory Jan 1970

Water Management Research In Arid And Sub-Humid Lands Of The Less Developed Countries: Second Annual Progress Report, Utah Water Research Laboratory

Reports

No abstract provided.

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Subcritical Flow At Open Channel Structures Bridge Constructions, Gaylord V. Skogerboe, Lloyd H. Austin, Kuan-Tao Chang Jan 1970

Subcritical Flow At Open Channel Structures Bridge Constructions, Gaylord V. Skogerboe, Lloyd H. Austin, Kuan-Tao Chang

Reports

The techniques previously employed by the writers for describing subcritical flow at open channel constrictions have been found valid for analyzing nonuniform flow in open channels. Combining the nonuniform flow analysis with the submerged flow ratings for various bridge geometrics has provided an analytical means for determining the backwater due to the bridge constrictions under “abnormal stage – discharge” conditions.

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Formulation And Solution Of Transient Flow Of Water From An Infiltrometer Using The Kirchhoff Transformation, Roland W. Jeppson Jan 1970

Formulation And Solution Of Transient Flow Of Water From An Infiltrometer Using The Kirchhoff Transformation, Roland W. Jeppson

Reports

No abstract provided.

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Determination Of Hydraulic Conductivity--Capillary Pressure Relationship From Saturation--Capillary Pressure Data From Soils, Roland W. Jeppson Jan 1970

Determination Of Hydraulic Conductivity--Capillary Pressure Relationship From Saturation--Capillary Pressure Data From Soils, Roland W. Jeppson

Reports

No abstract provided.

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Transient Flow Of Water From Infiltrometers--Formulation Of Mathematical Model And Preliminary Numerical Solutions And Analyses Of Results, Roland W. Jeppson Jan 1970

Transient Flow Of Water From Infiltrometers--Formulation Of Mathematical Model And Preliminary Numerical Solutions And Analyses Of Results, Roland W. Jeppson

Reports

The partial differential equation initial-boundary value problems which describe the three-dimensional axisymmetric flow of water from an infiltrometer through partially saturated soil are solved by finite differences using the alternating direction implicit method. Pertinent features which describe the flow characteristics obtained from 34 solutions for varying initial conditions and for 12 soil types are summarized in tables and figures. Relationships between such features as depth of penetration and lateral movement of the wetting front and rate of application and initial hydraulic head or tension in the soil are developed for several of these soils types from analyses of the results.

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Solution To Transient Vertical Moisture Movement Based Upon Saturation--Capillary Pressure Data And Modified Burdine Theory, Roland W. Jeppson Jan 1970

Solution To Transient Vertical Moisture Movement Based Upon Saturation--Capillary Pressure Data And Modified Burdine Theory, Roland W. Jeppson

Reports

Using finite differences and the Crank-Nicholson implicit scheme for solving parabolic type partial differential equations, a computer program has been developed for solving the one-dimensional, vertical movement of water in soils. The formulation of the initial boundary value problem is obtained by introducing a new dependent variable through the Kirchoff transformation to replace the hydraulic head. Data relating saturation (or moisture content) to the capillary pressure in the soil are used to define the hydraulilc properties of the soil which are needed in order to obtain a solution. The Burdine Theory has been implemented in the program to obtain the …

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Computer Simulation Of The Hydrologic-Salinity Flow System Within The Upper Colorado River Basin, M. Leon Hyatt, J. Paul Riley, M. Lynn Mckee, Eugene K. Israelsen Jan 1970

Computer Simulation Of The Hydrologic-Salinity Flow System Within The Upper Colorado River Basin, M. Leon Hyatt, J. Paul Riley, M. Lynn Mckee, Eugene K. Israelsen

Reports

Changes in the hydrologic equilibrium of a river basin resulting from resource development also produce changes in the quality pattern. Since the burden of quality maintenance must be shared by users (just as are quantities) predictions are needed for quality changes which might result from contemplated development at any specified location within the river system. This study reports the development of a computer simulation model of the water and salt flow systems within the Upper Colorado River basin. Because of the close relationship between the hydrologic and salinity flow systems, an understanding of the hydrologic system is essential to successful …

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A Hydrologic Model Of The Bear River Basin, Robert W. Hill, Eugene K. Israelsen, A. Leon Huber, J. Paul Riley Jan 1970

A Hydrologic Model Of The Bear River Basin, Robert W. Hill, Eugene K. Israelsen, A. Leon Huber, J. Paul Riley

Reports

As demands upon available water supplies increase, there is an accompanying increase in the need to assess downstream consequences resulting from changes at specific locations within a hydrologic system. The problem is approached in this study by hybrid computer simulation of the hydrologic system. Modeling concepts are based upon the development of basic relationships which describe the various hydrologic processes. Within a system these relationships are linked by the continuity-of-mass priciple which requires a hydrologic balance at all points. Spatial resolution is achieved by considering the modeled areas as a series of subbasins. The time increment adopted for the model …

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A Thermodynamic Analysis Of A Primary Waste Stabilization Pond, David W. Hendricks Jan 1970

A Thermodynamic Analysis Of A Primary Waste Stabilization Pond, David W. Hendricks

Reports

Traditional design practice for waste stabilization ponds is based upon the premise that sufficient photosynthetic oxygen must be produced within the pond to satisfy oxygen requirements of the incoming waste flow. Thus, because algae production is proportional to pond surface area, surface organic loading rate is a principal design criterion (hydraulic detention time is the other) . That a possible adverse energy trade exists in the sequence of coupled reactions (aerobic waste degradation-photosynthesis) has been largely ignored. This work is focused on quantitatively articulating this energy trade, in terms of algae produced vis a vis waste degraded. This is done …

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Final Report: Wasatch Airborne Seeding Program, Geoffrey E. Hill Jan 1970

Final Report: Wasatch Airborne Seeding Program, Geoffrey E. Hill

Reports

No abstract provided.

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Bacterial Absorption On Soils--Thermodynamics, David W. Hendricks, Frederick J. Post, Deorao R. Khairnar, Jerome J. Jurinak Jan 1970

Bacterial Absorption On Soils--Thermodynamics, David W. Hendricks, Frederick J. Post, Deorao R. Khairnar, Jerome J. Jurinak

Reports

Laboratory studies on the adsorption of bacteria onto soils and activated carbon were undertaken to evaluate the role of the process in removal of bacteria from groundwater. It was hypothesized that removal of bacteria from water passing through soil would be primarily due to adsorption in which case the bacteria would behave in a manner similar to colloidal particles or chemical molecules. The basic kinetics of uptake of Staphylococcus aureus were determined on activated carbon, a highly adsorbing material chemically speaking. Once the technique was worked out and adsorption demonstrated to take place, sand, clay, and Mendon silt loam were …

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Systems Analysis Of Hydrologic Problems, J. Paul Riley, Diana Averett Jan 1970

Systems Analysis Of Hydrologic Problems, J. Paul Riley, Diana Averett

Reports

Introduction: Increasing national and international interest in water resources in recent years has stimulated much new activity and progress in hydrology. It is now generally recognized that the science of hydrology is basic to an understanding of water resources problems and to planning for water resources development. Accompanying this demand upon the science of hydrology is an urgent need for improved education at the university level. In resopnse to this need for improved education, the First International Seminar for Hydrology Professors was held at Urbana, Illinois, in July 1969. The Second International Seminar was held at Logan, Utah, during August …

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Computer Simulation Of Water Resource Systems At Utah State University, J. Paul Riley Jan 1970

Computer Simulation Of Water Resource Systems At Utah State University, J. Paul Riley

Reports

Introduction: The problems of managing water-resource systems are basically those of decision making based upon a consideration of the physical, economic, and sociological processes involved. These processes are strongly interrelated and constitute a dynamic and continuous system. Any combination of these interrelated and numerous system variables yields a management solution. At Utah State University the problem of investigating system response to various possible management alternatives is being approached by hybrid computer simulation. The concept of simulation is fundamentally simple. Basically, it is a technique of analysis whereby a model is developed for investigating the behavior or performance of a dynamic …

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An Examination Of Approximately Simultaneous Salt Lake Valley And Cache Valley Clearing (Ventilation) Indexes, George W. Reynolds, William Mcneill, Floyd Johnson, Janet Cleary Jan 1970

An Examination Of Approximately Simultaneous Salt Lake Valley And Cache Valley Clearing (Ventilation) Indexes, George W. Reynolds, William Mcneill, Floyd Johnson, Janet Cleary

Reports

The Clearing Index is a numerical estimate of the contamination dispersal capability of the atmosphere. Between July, 1969, and June, 1970, 192 rawinsonde flights were made in the Cache Valley at approximately the same time as officially scheduled flights at the Salt Lake City Weather Bureau Airport Station. Clearing Indexes were computed from various combinations of Salt Lake Valley and Cache Valley rawinsonde and maximum surface temperature data. These were examined from the viewpoint of recommending a standard procedure for providing Clearing Indexes on a daily basis for Intermountain valleys. The primary conclusions were that: 1. Actual Salt Lake Valley …

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