Engineering Commons^™

Simulation Of Periodic Tank Reactors, Noshir Pirojshaw Mistry

Dissertations

Normally it is assumed that the steady state mode of operation is most desirable for the design of the chemical reactor system. However it appears that this assumption may not be correct in many cases.

In the present work disturbances of various types were externally created and forced on a system comprising an isothermal continuous stirred tank reactor. The effects of these purposefully created disturbances were investigated by mathematically modelling the system and simulating it on a digital computer.

The change in reactor performance, as defined by the percentage change in the production rate from the steady state value, can …

Measurement Of Fluid Velocities In A Simulated Heat Pipe, Lewis Collin Moore

Mechanical Engineering ETDs

Velocity components of numerous geometries may be measured with the laser Doppler technique. Combinations of system parameters were investigated that were useful for constructing a two-dimensional velocimeter for a tube with porous walls. A method was developed which combined a local oscillator with a crossed-incident beam using backscatter at very small angles from the longitudinal axis. Seeding requirements, electronics signal processing, permeability measurements, and measurement point constraints were investigated. Preliminary fluid velocity results were obtained, and recommendations are made for further improvements to overcome the difficulties encountered in the current investigation.

Response Of The Lower Vertebral Column To Caudocephalad Acceleration, A. Peter Vulcan

Wayne State University Dissertations

This dissertation is concerned with the measurement of the response, in those areas of the vertebral column where fractures are most common, when the seated human is subjected to caudocephalad acceleration. Such accelerations and consequent vertebral fractures are experienced not only in ejection from aircraft, but also in survivable helicopter and aircraft crashes, and in certain types of falls. It is intended that the measurements should provide a better understanding of the mechanisms of vertebral fracture and data for the formulation of an appropriate mathematical model.

Contributions To The Specific Heat Capacity Of Nickel, Iron, And The Alloy Ni3Fe, Thomas Gilman Kollie

Doctoral Dissertations

The specific heat capacity at constant pressure C_p of a ferromagnetic solid is assumed separable into six contributions - that due to the dilation of the lattice C_d, that due to the harmonic oscillations of the atoms C_vh, that due to the anharmonic oscillations of the electrons C_va, that due to changes in energy distributions of the electrons C_ve, that due to changes in the magnetic coupling among the electrons C_vm, and that due to atomic rearrangements C_vw. Expressions appearing in the literature for these contributions, which …

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.

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 …

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.

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 …

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.

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 …

Correlation Of 1/F Noise With Threshold Drift In Mosfet's, John Peter Rooney

Theses

A brief review of the fundamentals of MOSFET's is given. A correlation between threshold drift and surface states is made, with a following correlation between surface states and 1/f noise. It therefore follows that MOSFET's with a high 1/f noise level will drift more than those with a low level of 1/f noise. Experiments were carried out to show this effect, but no clear cut conclusions can be drawn from the experimental work.

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.

Concepts In Lsi Servo-Control-Electronics, Alfons Alfred Tuszynski

Dissertations

This thesis deals with the engineering aspects of control electronics. It examines modern concepts of servo-control theory in the light of recent developments in the technology of monolithic circuits. Applicational considerations are slanted towards Aerospace standards of reliability and power-consumption economy.

Conclusions drawn from the discussion of fabrication constraints and performance requirements lead to a preference for digital implementations. Yield problems on one hand and aging effects on the other greatly reduce the feasibility rating of analog arrays.

Current practice in servo-control electronics revolves around purely analog implementations, sampled-data systems and Primitive on-off arrangements. The motivation behind the status quo …

Financing The Nuclear Fuel Requirements Of Public Utilities, Peter A. Lewis

Theses

A major portion of new electric generating capacity will be nuclear powered. The change to nuclear power will require large outlays of capital not required with conventional fuels to finance nuclear fuel inventories. Nuclear fuel financing requirements are unique because nuclear fuel is not consumed in the same manner as conventional fuels. Financing has not been a problem to date because nuclear fuel can be obtained only through lease from the Atomic Energy Commission. This arrangement will be terminated by June 30, 1973 and from that date on all nuclear fuel must be privately owned. Electric utilities have shown an …

A Rheological Equation Of State For Blood At Low Shear Rates, Anatoly Dritschilo

Theses

In this work a new rheological equation of state is presented and its application to blood is studied. The equation considered is a linear combination of Newtonian and non-Newtonian contributions to the apparent viscosity. The general form of the equation is

T_ij =-(A + Be^{-1/C|(.5)Δi/j:Δj/i|1/2})Δij

Data from the literature were used to test the equation by generating curves of measured torque (T/L) versus applied shear rate (Ω) that would characterize the behavior of blood at all red cell concentrations and all shear rates in the Gilinson, Dauwalter and Merrill viscometer. The constants for the equation were …

Experimental Investigation Of Submerged, Incompressible, Turbulent, Impinging Jets, David Tzeh-Hsian Lee

Theses

Measurements concerning various flow parameters of jets impinging on a smooth lucite plate and a heated metal plate have been carried out. In particular, it is shown that the potential core length of a jet is a function of the Reynolds number and of the jet diameter. It has also been demonstrated that impinging jets behave in many important respects like free jets, except in the immediate vicinity of the target plate.

The flow behavior in the wall jet zone was investigated experimentally, and a satisfactory agreement with the results of the previous investigators was found. The maximum velocity decay …

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 …

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 …

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 …

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 Method For Plotting Isohyetal Maps Using An Analog Computer, Maurice George Kirwan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The ability of the analog computer to stimulate physical phenomena is used in conjunction with a resistance paper model of the Walnut Gulch watershed in Arizona to plot constant precipitation maps from data obtained from recorded rainfall. Voltages which are proportional to rainfall at a specific raingage, located at scaled points of the resistance paper model, set up an electric field on the resistive sheet which is detected and processed by the computer. The detected potential is compared to a reference potential, or "precipitation value", and the necessary analog networks allow plotting of the equipotential line which is directly analogous …

Formulation Of A Mathematical Model For The Allocation Of Colorado River Waters In Utah, Rick L. Gold

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

This report is linked with the work done in fulfillment of the first objective of a research project now underway at the Utah Water Research Laboratory. The project, entitled "Application of Operations Research Techniques for Allocation of Colorado River Waters in Utah," is a matching fund grant by The Office of Water Resources Research of the United States Department of the Interior. The project has the following objectives: (1) formulate the mathematical model of that part of the state that can receive Colorado River water, (2) optimize the allocation model under different demand levels and study the economic effects of …

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).

A Study Of Precipitation Characteristics For Utah, Tsing-Yuan Chang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Data on monthly precipitation for three areas of Southern Utah--Beaver, Cedar City and Ephraim--and three areas of Northern Utah--Salt Lake City, Ogden and Logan--where a series of measuring stations were arranged as traverses from the valleys to the mountain tops; were assembled and analyzed.

The relationships between elevation and precipitation amounts were shown. The Southern Utah stations were drier at the same elevations than the Northern Utah stations and the differences became greater as the elevations increased. There was a close correlation between the high elevation and low elevation stations in the same traverse even with the above divergence.

A …

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 …

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.

Reflection And Transmission Of Dipole Radiation In Presence Of An Extended Boundary, Rough And Smooth, Byong Ki Park

Electrical and Computer Engineering ETDs

Several different forms of integral solutions exist to the problem of dipole radiation in presence of a half space with plane boundary, all of which can be easily shown to agree with one another by transformation. For the evaluation of these integrals, a number of assumptions are usually made on some parameters in the expressions such as the medium property, the wavelength and so on. Unfortunately, however, even with these simplifying (but meaningful) assump­tions, practically useful results for the dipole radiation problem are still lacking. Also it appears that there is no theory of dipole radiation when the plane boundary …