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Experimental Investigation Of The Hydrodynamic Stability Of Flow In Rotating Pipes Using Thermistors, Hassan M. Nagib, Ludwig Wolf Jr.

Symposia on Turbulence in Liquids

The hydrodynamic stability of flow in a rotating pipe Is investigated experimentally using thermistors. The experimental apparatus consists of a rotating pipe made of lucite, 3-1/4 inch inside diameter, six feet long, equipped with porous plugs at the ends to minimize recirculation. The working fluid is water and a range of axial and tangential Reynolds numbers up to 7,000 and 20,000, respectively, is covered. Thermistors were chosen for this study since their high electrical resistivity yields strong signals which permit the use of inexpensive and convenient electronics. They also have a high temperature coefficient of electrical resistance which minimizes the …

The Structure Of A Turbulent Water Jet, Philip J. Morris

Symposia on Turbulence in Liquids

Experimental studies are made to determine the structure of a turbulent water jet.

The paper is divided into two parts. The first gives practical information about the techniques and instrumentation developed to make measurements with hot-wire anemometers in water. A short theoretical discussion is given on the dynamic response of heated fibre in liquids. The second part reports on the results obtained in a one-inch water jet at Reynolds numbers between 12,000 and 20,000. Mean axial velocity measurements are made in the initial five diameters of the jet and the results are used to predict the nature of the vortex …

Author Index, University Of Missouri--Rolla

Symposia on Turbulence in Liquids

No abstract provided.

An Optimization Technique Applied To The Determination Of Orthotropic Material Properties Using Dynamic Response Test Data, Ronald L. Webster

Theses and Dissertations

A knowledge of the behavior of a material under loading similar to expected service loading is required before that material can be used effectively in the design process. Without sufficient mechanical properties data, the design process degenerates to a time consuming and often costly "build, test and modify" type of program. Obviously, this trial and error approach leaves much to be desired.

A Computer Procedure For The Identification Of Beam, Spring, And Damping Parameters Of An N-Mass Model Using Transient Data, Lynn A. Christiansen

Theses and Dissertations

If, however, one could develop a model for a given physical system, that is a model which can be described in terms of lumped masses, springs beams, and dashpots and then identify the parameter simply by processing acceleration data such as that obtained from drop tests or shaker tests, the task of identification is greatly simplified.

Analytical Study Of Heat Conduction And Thermal Stress In Solids With Pressure Dependent Contact Resistance, Dhruvkumar S. Patel

Theses and Dissertations

In the usual thermal stress analysis of a body, the stresses are found for a predetermined temperature distribution. In problems involving composite materials, thermal contact resistance between materials can significantly affect the temperature distribution. The contact resistance is normally a function of the contact pressure and thermally induced stresses can affect the temperature distribution. Thus in composite bodies the thermal stress problem and the heat transfer problem may be coupled and require a simultaneous solution of both problems.

Water Injection In An Automobile Gas Turbine Combustion System, Billy Ray Jackson

Theses and Dissertations

"GENTLEMEN, JUNK YOUR ENGINES!" This title of a recent periodical article [1]* catches some of the expectation for the wedding of the Automobile and the Gas Turbine, The nuptials cannot be completed though, unless two problems are overcome: 1) high fuel consumption, and 2) high operating temperature. The first problem is solvable by the use of heat regeneration and much work has been done in this area [2][3] [4]. The solution of the second problem of high operating temperature was the basis for this thesis. The method of solution was by water injection into the combustion gases prior to entrance …

Optimization Of Physical Properties Of Hydraulic Cushion Cells For Vehicle Impact Restraint, William Evans Hughes

Theses and Dissertations

In recent years, the United States has witnessed a vast expansion of its internal highway system. Concurrently the number of vehicles has increased as has the average yearly milage per vehicle. Unfortunately, along with increased vehicle use there has been an alarming increase in annual loss of life and property due to traffic accidents. Statistics verify that the modem freeway systems greatly reduce dangerous head on collisions but the rate of accidents due to collisions with fixed objects in or near the roadway has increased almost 50 percent in the past thirty years.^1 In 1966, about 13>300 deaths were …

Large Deflection Analysis Of Laterally Restrained Reinforced Concrete Slabs, Satwant Singh Rihal

Civil Engineering ETDs

This dissertation is an attempt to analytically predict the large deflection behavior of orthogonally reinforced concrete slabs. The problem considered is that of a laterally restrained, simply supported square slab under uniform loading. The range of loading considered is from zero load to the load at which yielding first commences in the steel reinforcement.

This problem is first formulated using the classical large deflection theory of homogeneous plates. This formulation is based on a constant overall stiffness for the entire slab.

A modified large deflection theory is next developed for reinforced concrete slabs. In this theory concrete on the tension …

A High Voltage Regenerative Pulse Modulator, James D. Doss

Electrical and Computer Engineering ETDs

This paper describes the design of a High Voltage Pulse Modulator that employs positive feedback to generate output pulses of variable width. The modulator is intended for use as a switching device to drive the modulating anode of a five-cavity klystron. The klystron develops more than one million watts of peak power at a frequency of 805 MHz, with duty factors up to 12%. The modulating anode voltage drive requirement is approximately 80 kV with the current drain being of the order of 0.01 ampere. The total modulator current output will be approximately one ampere with most of the current …

Improved Numerical Techniques And Solution Of A Separated Interaction Of An Oblique Shock Wave And A Laminar Boundary Layer., Ben Douglas Gay

Mechanical Engineering ETDs

Initial, boundary and differencing techniques of numerical gas dynamics were improved, and a separated interaction of an oblique shock wave and a laminar boundary layer was solved numerically.

The computing time of a Lax-Wendroff differencing technique was reduced 60 percent by making algebraic changes. Inflow and wall boundary techniques were improved, and the new techniques were verified by satisfactory solutions of plain laminar boundary layers and unseparated interactions of oblique shock waves and laminar boundary layers. The differencing technique was numerically unstable for separated interactions.

Results of a sample all-centered differencing technique agreed with those of a Lax-Wendroff technique for …

Diffusion Coefficients Of D-Glucose In Aqueous Carboxymethylcellulose And Carboxypolymethylene Solutions, A. L. Huang, S. V. Desai, Robert M. Wellek

Chemical and Biochemical Engineering Faculty Research & Creative Works

A micro interferometric method was used to determine pseudo-binary, molecular diffusion coefficients for diffusion of D-glucose in aqueous carboxymethylcellulose (CMC) and aqueous carboxypolymethylene (Carbopol) solutions. An initial solute concentration of about 9 wt. % D-glucose in the aqueous polymer solutions was used. The polymer concentrations for the CMC solutions ranged from 1.2 to 2.2 wt. % and for the Carbopol solutions from 0.18 to 0.28 wt. %. Diffusion coefficients were determined as a function of reduced solute concentration, both with and without the effect of solution volume change during diffusion being considered. © 1969, American Chemical Society. All rights reserved.

Cold-Rolled Austenitic Stainless Steel: Materials Properties And Structural Performance, George Winter, S. T. Wang

CCFSS Library (1939 - present)

The cold reduction in thickness of austenitic stainless steel sheet brings about the following significant characteristics of material properties: 1) higher strength with an increasing amount of cold working, 2) more pronounced anisotropic material properties with increasing cold working, 3) stress strain relations different in tension and compression and depending on directions, and 4) nonlinear stress strain curves with relatively low elastic limits, especially in longitudinal compression. In addition, local buckling is encountered in thin walled structural members. These are the problems associated with the structural design of stainless steel members. The purpose of this investigation is to develop the …

Stability Analysis Of Nuclear Reactor Feedback System, Ashok K. R. Bizzul

Electrical and Computer Engineering ETDs

A nuclear reactor feedback control system is analyzed for stability conditions in frequency domain by two methods. The nuclear reactor is modeled by a single delayed neutron group model, and the methods of analysis are Popov's analysis and describing function analysis. The feedback system with linearized nuclear reactor model is analyzed by Popov's method. A more exact non-linear reactor model is used in the feedback control system for describing function method of anal­ysis. It is found by both methods that the system is absolutely stable. But describing function analysis gives greater insight to the study of the relative stability of …

A Numerical Study Of The Coanda Effect., Soloman P. Chavez

Mechanical Engineering ETDs

A numerical solution for the flow in a two-dimensional bistable fluid amplifier is obtained. A minimum Reynolds number is found below which attachment will not occur. The study shows the quality of attachment and attachment point varying with Reynolds number.

Military Environics - Water And Waste, James Anthony Mahoney

Civil Engineering ETDs

This thesis summarizes the activities of the United States Military Services effort, in the areas of water supply, waste water treatment, and solid waste disposal for personnel of the Armed Forces and their dependents. This thesis surveys the state-of-the-art of the present sanitary facilities in the United States and abroad as associated with the military environment. Chapter I compares the responsibilities of the military installation engineer to that of a municipal public works director. Discussed are the service laboratories and their locations. Chapter II includes supply, treatment, design, distribution and storage of water. It is concluded with a reference section …

Reliability Aspects Of Micropower Majority-Charge Logic, James T. Henderson

Electrical and Computer Engineering ETDs

This thesis is a study of the reliability aspects of micropower majority-charge techniques as applied to fundamental-mode clocked-se­quential circuit design. A· sample sequential circuit is used as the basis for the extension of previously developed circuitry. This previously developed circuitry is applied to the sample sequential circuit in the form of Micropower Majority-Charge Flip-Flops. These flip-flops are very immune to transient noise and offer reduced power consumption over standard integrated circuit flip-flops by pulsed power application. The use of AND gates and OR gates with amplifiers and NAND gates or NOR gates for memory elements is reported. It is shown …

Vertical Force Measurement For The Chaparral Rocket Sled, John C. Gustafson

Mechanical Engineering ETDs

A study of the feasibility of instrumenting existing structures with strain sensing elements to measure a specific component of force transmitted by the structure in use has been conducted. A specific structure, the front slipper assembly of the Chaparral rocket sled, was used in this study. The developmental phase of this work was conducted through the use of a model study. The model studies were made to determine appropriate stress raisers and locate strain gages so the desired force component could be measured. The actual structure was modified in accordance with the results of the model tests. Calibration tests and …

An Experimental Study Of Radiation Effects On Metal-Insulator-Semiconductor Structures., Robert James Kopp

Electrical and Computer Engineering ETDs

It is heuristically desirable to automatically display the capacitance-versus-voltage {C-V) and conductance-versus­voltage (G-V) curves (including hysteresis) of metal-insula­tor-semiconductor capacitors at times subsequent to irradiation. Ultimately, these data will be used to assess the effects of ionizing radiation on the character of the surface states within the device. The purpose of this thesis is to describe in some detail the operation of circuitry that has been designed and fabricated at the University of New Mexico, and that is currently in use here in making automated measurements of this type. Also, the data are placed in a descriptive context involving a compendium …

Improved Numerical Techniques For Three Dimensional Transient Conduction Coupled With Surface Radiation And Variable Emissivities, Jimmie H. Smith

Mechanical Engineering ETDs

The problem of transient conduction combined with surface radiation and variable emissivities is solved numerically. The existing, but little used, multidimensional Douglas-Peaceman-Rachford alternating-direction-implicit (ADI) technique for finite differencing is chosen as the best available. It is modified and applied to the three-dimensional transient heat equation with source term. Techniques for blocking conduction in excluded directions are demonstrated. Quasi-linearization is used to combine the radiant enclosure calculations with the transient conduction calculations. That is, on an alternating basis, a time step in conduction is followed by a radiant enclosure solution. The radiant enclosure problem is solved in a novel manner, combining …

A Computer Multistage Optimization Method On Ethane Decomposition, Jonathan K. Ma

Chemical and Biological Engineering ETDs

The prediction of conversions and product distributions under various conditions is of prime interest in the process design of an optimum reactor. This is a very difficult task when a complex reaction is under consideration; since reactions take place simultaneously the relationship of the individual reaction and the over-all product distribution and their correlation with the control variables are hard to define. This study is an application of the free radical mechanism of the thermal decomposition of ethane to calculate the product distribution. Since this is an endothermic reaction, the temperature profile is the control variable. The relationship between the …

A Study Of Evaporation And Evapotranspiration In Peru, Fernando Chanduvi-Acuña

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Twenty-four equations for estimating evaporation and/or evapotranspiration were compared with measured Piche evaporation. At least 1728 months of records from 12 Peruvian stations were analyzed in this study.

Computer programs were developed to work this study and the results were compared by plotting.

It has been found that the equation that best fits the Piche evaporation in the low elevation stations in Peru is Christiansen's formula (ET2) which was used as a base for his formula for Class A pan evaporation (EVC).

Ehv Ac Parallel Transmission Line Calculations With Application To The Near Resonance Problem, A. Norton Chaston

Faculty Publications

The use of shunt reactors with EHV transmission lines has introduced new problems, one of which is induction of high voltages on a de-energized circuit of two parallel lines. This paper presents the matrix equations used in developing a digital computer program which takes into account the effects of electromagnetic induction, electrostatic coupling, distributed lines, and transposition. The computer program may also be used to calculate the effects of shunt reactors, series capacitors, and loads. The equations can be adapted to a wide range of applications, although the examples for this paper have been limited to the near resonance problem …

A Study Of Turbulent Heat Transfer From Smooth And Rough Flat Plate Surfaces, Philip Tsungwen Lin

Theses and Dissertations

Experimental investigations of the surface roughness effect on heat transfer have been extensively conducted since the initial work by Cope; however, they were mostly limited to internal flow geometries--circular tubes, annuli or rectangular ducts.

A Study Of Turbulent Heat Transfer From A Flat Plate With Transverse Temperature Variations, John C. W. Kwan

Theses and Dissertations

Heat transfer in turbulent flow from external surfaces has been investigated extensively in the past. Most of the theoretical and experimental work deals with a two dimensional boundary layer on isothermal or uniform heat flux surfaces with longitudinal temperature variation. However, little attention has ever been paid to the case in which the temperature of the plate varies transversely. This is a three dimensional problem due to the spanwise variation of the thermal boundary layer. The most elementary example of this is the boundary formed by the sudden temperature impulse that acts transversely across a flat plate as shown in …

The Irish Plumbing And Heating Engineer, May 1969 (Complete Issue)

Building Services Engineering

No abstract provided.

A Study Of The Aerobic Treatment Characteristics Of The Raffinates From A Reverse Osmosis Waste Water Reclamation Plant., Joseph Charles Jennett

Civil Engineering ETDs

Water Supply

In the United States today the problem of pollution of our surface water is an ever increasing one. Conventional processes of treating waste water are approaching their effective limit in removing pollutants. Both the population and the per capita consumption of water are increasing. More and more often the idea of complete water reclamation is coming under consideration.

Aspects Of The Effects Of Cold-Forming On The Properties And Performance Of Light-Gage Structural Members, Jairo Uribe, George Winter

CCFSS Library (1939 - present)

INTRODUCTION General Background Cold-Formed Steel Construction constitutes today an industry of significant importance. Its products supplement the usual hot-rolled steel structural members and can be divided into two broad categories: a) structural sections whose main purpose is to carry loads, and b) panels and decks which in addition should provide useful surfaces or serve other functions. Cold-formed steel structural members are made of hot rolled or cold reduced sheet or strip steel by any of the cold-forming methods described below. Thicknesses range in general from No. 28 Gage (0.0149 in.) to No. 10 Gage (0.1345 in.) but some formed shapes …

Panel Discussion, J. Allen Overton Jr., John F. O'Leary, Bryce I. Mcdonald Jr.

Mining Environmental Conference

No abstract provided.

Summary And Conclusions Of The Mining Environmental Conference, Thomas Ware

Mining Environmental Conference

No abstract provided.