Engineering Commons^™

Methods For Predicting The Influence Of Intense Sound, Steady Flow, And Elevated Temperature On The Acoustic Performance Of Automotive Exhaust System Components, Richard Chuka Oboka

Doctoral Dissertations

"The principal objective of this investigation was to study the feasibility of developing laboratory techniques for automobile-exhaust muffler design in order to reduce the amount of on-vehicle trial-and-error testing currently required. The investigation included (1) improving the capability of existing laboratory equipment to simulate the conditions in automobile exhaust (i.e., high-amplitude pressure waves, steady flow, and elevated temperature), and (2) theoretical and experimental studies of typical acoustic elements (side-branch resonators, expansion chambers, louvered tubes) used in muffler design. The sound fields used for these studies included pure tones, single pulses (tone bursts), random noise, and simulated automobile exhaust noise.

Empirical …

Film Boiling Of Freon 113, Normal Pentane, Cyclopentane, And Benzene From Cylindrical Surfaces At Moderate Pressures, Gary Joseph Capone

Doctoral Dissertations

"An investigation of film boiling heat transfer in saturated pools of liquid Freon 113, Normal Pentane, Cyclopentane, and Benzene was made. The fluids were boiled from copper, cylindrical heat transfer surfaces, 3 inches long, and 0.55, 0.75, and 1.00 inch in diameter. The heat transfer elements were positioned horizontally in an autoclave and tested at moderate pressures of up to a pressure of 242.5 psia for Normal Pentane.

The experimental data are discussed and compared with known film boiling correlations. The known correlations were found to be inadequate in predicting heat transfer coefficients as a function of pressure, temperature difference …

Analysis Of Continuous Curvilinear Structures By Infinite Matrix Series Methods, Trinh-Ngoc Rang

Doctoral Dissertations

"The objective of this dissertation is to present two methods of structural analysis for continuous curvilinear frames by using infinite matrix series as an extension of the well-known moment-distribution method. The sum of all unbalanced moments and thrusts relaxed at joints of a continuous system can be expressed in a compact and exact mathematical expression, which is in terms of the sum of a convergent infinite matrix series. With these unbalanced forces at joints, the final support forces may be calculated in a single stage of distribution and carry-over. The convergence of the balancing process is also demonstrated. Approximate results …

Nonlinear Optimum Design Of Dynamic Damped Structures, Mark E. Botkin

Doctoral Dissertations

"A method to optimize the weight of plane frames subjected to dynamic loads is presented. Restrictions are imposed upon the maximum dynamic stresses and displacements, desirable section moduli of the constituent members, and the range of values allowed for natural frequencies. Various considerations for rigid frame design include damping, the P-Δ effect, static girder loads, static column loads and girder shears transferred to the columns. A finite difference approach is presented to evaluate the shock spectrum which is used in conjunction with modal superposition to obtain the peak upperbound dynamic displacements and stresses for multistory and multibay frames. The displacement …

Initial Surface Reactions And Nucleation Kinetics Of Boron On Atomically Clean Molybdenum Substrates, Richard Eugene Moore

Doctoral Dissertations

"A study of the chemical vapor deposition (CVD) of boron from boron triiodide (BI₃) on molybdenum has been done with field emission microscopy (FEM) and low energy electron diffraction (LEED).

A correlation of the efficiency by which BI₃ is effectively dissociated to form adsorbed boron, and the temperature of the substrate has been shown through work function measurements on the boron covered molybdenum field emitter surfaces. The boron-induced work function change of molybdenum has been shown to be in agreement with a theoretical model which predicts positive, as well as negative work functions for adsorbate-substrate systems. It …

Implementation Of Recursive Algorithms For Delay-Time Estimation Using The Fast Walsh Transform, Donald Robert Nelson

Doctoral Dissertations

"Use of the fast Walsh transform to resolve noisy signals into Walsh function series to digitally implement maximum-likelihood parameter estimators for real-time use is investigated. Realization of estimators which seek a null in the derivative of the log-likelihood function, instead of direct maximization, results in feedback algorithms which yield considerable savings in computation time and storage. Performance of these feedback delay-estimation algorithms is characterized in terms of mean-squared error (MSE) and response to a delay step by Monte Carlo simulation. The effect of changing the number of points in the transform on the MSE is also investigated. Hard limiting of …

Film Boiling Of Benzene, Freon 113, Freon 11, And Normal Pentane From Horizontal Surfaces At Atmospheric Pressure, Richard Stanley Kistler

Doctoral Dissertations

"A film boiling study was conducted with five different area flat plates at atmospheric pressure for benzene, Freon 113, Freon 11, and n-pentane. The heat transfer surface was horizontal for all tests.

The data were compared to the correlations commonly used for heat transfer. The common correlations were found to be in error for small surface sizes, but adequate for all fluids except benzene for the largest surface, a semi-empirical equation which correlates the available data as a function of surface diameter was derived and discussed"--Abstract, page iii.

An Application Of Residual Relaxation To Mathematical Simulation Of Petroleum Reservoirs, Grufron Achmad

Doctoral Dissertations

"Stability and convergence have long been primary concerns in the application of numerical techniques to the simulation of petroleum reservoir performance. An iterative method based on sequentially reducing the residual to zero at each grid point has been developed. It has been shown analytically that this residual relaxation method is stable, convergent, and consistent.

A three-phase areal model was developed to simulate a hypothetical homogeneous petroleum reservoir, and various computational methods were tested with this model. The residual relaxation method developed in this study (RELAX) was found to converge as rapidly as SIP, and much faster than either LSOR or …

Linear Stability Of Non-Parallel Flow In The Entrance Region Of Ducts, Francis Chung-Ti Shen

Doctoral Dissertations

"An investigation is made of the linear stability of the developing flow of an incompressible fluid in the entrance region of annular ducts, circular tubes, and parallel-plate channels. Small axisymmetric disturbances for annular duct and tube flows and small two-dimensional disturbances for channel flow are considered in the analysis. In formulating the stability problems, account is taken of the transverse velocity component of the mainflow. This results in the modified Orr-Sommerfeld equations, one for annular duct and tube flows and the other for channel flow. The mainflow velocity fields utilized in the stability analysis are those from the solutions of …

Rock Fragmentation By Subsurface Thermal Inclusions - A Finite Element Study, Mahendrakumar Ramkrishna Patel

Doctoral Dissertations

"Although rock tunneling machines are being used extensively with performance and cost advantages over traditional drill and blast methods, their usefulness for hard rock excavation is far from being practical due mainly to the inability of present day mechanical cutters to penetrate these rocks economically. Among various novel techniques that are being investigated, internal heating methods seem to be the most promising. This investigation is concerned with a feasibility study of thermal rock fragmentation using heat to create in-depth thermal inclusions.

The three-dimensional problem of in situ rock fragmentation involves parallel rows of equidistant holes drilled to a constant depth. …

A Study Of The Dynamic Loading Of Hydrodynamically Lubricated Journal Bearings, Nader Khorzad

Doctoral Dissertations

"The analytical and experimental investigation presented here examined the response of a full journal bearing to a unidirectional dynamic load. Frequency response of the bearing at different eccentricity ratios was investigated. It was concluded that the response of the bearing varies with eccentricity. The experimental data obtained was compared to an analytical model which considered inertial, damping, and elastic characteristics of the lubricant film. An investigation of film pressure revealed that the pressure due to journal center acceleration is smaller than the hydrodynamic and squeeze-film pressures"--Abstract, page 1.

Numerical Simulation Of Heat, Mass, And Momentum Transfer In An Atmospheric Boundary Layer, Darrell W. Pepper

Doctoral Dissertations

"Considerable interest has developed in recent years to understand transport phenomena in thermally stratified boundary layers. More complete knowledge in this field is needed to improve the prediction of the diffusion of air pollutants in the lower atmosphere as well as in forecasting air-water circulation for weather conditions.

The atmospheric boundary layer is modeled using the equations of continuity, momentum, energy, and concentration. Closure of this set of partial differential equations is hindered by the turbulence terms. Using turbulence kinetic energy, the system of equations is closed by internally determining the exchange coefficients of heat, mass, and momentum along with …

Premartensitic Elasticity Of Fe-Ni Invars, Bryce Linn Shriver

Doctoral Dissertations

"The premartensitic temperature dependence of ultrasonic wave propagation in Fe-30 pct Ni polycrystals and Fe-32 pct Ni single crystals was measured by using a continuous wave technique. As the temperature was lowered to within 10°C of the M_s, a nonlinear decrease of the relative shear velocity was observed. This effect is related to dislocation stacking fault instabilities which may trigger the martensitic phase transformation. In addition, the single crystals show a frequency dependence of the shear elastic constant C' well above the M_s. The dispersion is believed to be caused by fluctuations in the anisotropic molecular …

Dynamic Instability And Ultimate Capacity Of Inelastic Systems Parametrically Excited By Earthquakes, Wu-Hsiung Tseng

Doctoral Dissertations

"A procedure of analysis is presented for determining the dynamic instability and response of framed structures subjected to pulsating axial loads, time-dependent lateral forces, or foundation movements. Included in the analytical work are the instability criterion of a structural system, the finite element technique of structural matrix formulation, and the computer solution methods.

The dynamic instability is defined by a region in relation to transverse natural frequency, longitudinal forcing frequency and the magnitude of axial dynamic force. The axial pulsating load is expressed in terms of static buckling load for ensuring that the applied load is not greater than the …

Nucleate Boiling From Polymer Coated Surfaces., David Franklin Warner

Doctoral Dissertations

"This study consisted of an examination of both the effects of nucleate boiling on polymer coated surfaces and the effects of the polymer coated surfaces on the nucleate boiling curve. The nucleate boiling curve (the curve resulting from plotting heat transferred per unit area versus the temperature difference between the boiling surface and the liquid pool) of the polymer coated surfaces were compared with the nucleate boiling curve of gold-plated surfaces with no polymer coat and it was found that the thicker the polymer coat, the more the curve deviated from that of the metal uncoated surfaces.

All surfaces were …

A Study Of Homogeneous Catalysis By High-Pressure Kinetics. The Mechanism Of Catalysis Of A Diels—Alder Reaction, Bruce E. Poling, Charles A. Eckert

Chemical and Biochemical Engineering Faculty Research & Creative Works

The application of high-pressure kinetics as a tool to investigate the detailed mechanism of catalysis of a reaction is demonstrated. Activation volumes have been determined for the Diels-Alder addition of 2, 3-dimethylbutadiene to n-butyl acrylate, both uncatalyzed and catalyzed with AICI3. Also, partial molal volumes of reactants and products have been measured. From these data it is shown that the volume profile along the reaction coordinate is similar for both the catalyzed and uncatalyzed reactions. Further, both reactions proceed by a concerted one-step mechanism through a compact transition state with maximum accumulation of double bonds. Thus, the role of the …

Analysis Of Multistory Frames With Light Gauge Steel Panel Infills, Craig J. Miller, Robert G. Sexsmith, Arthur H. Nilson

CCFSS Library (1939 - present)

PREFACE This report was originally presented as a thesis to the Faculty of the Graduate School of Cornell University in partial fulfillment of the requirements for the degree of Doctor of Philosophy, conferred in August 1972. The author wishes to thank Professor Arthur H. Nilson, Project Director, and Professor Robert G. Sexsmith, Principal Investigator, for the help and guidance that made this work possible. This investigation was supported by the American Iron and Steel Institute.

Microprogramming For Probability Distribution Sampling, Theodore Gyle Lewis

Electrical and Computer Engineering Faculty Research & Creative Works

Microprogramming of special instructions for sampling of random variates from any probability distribution is a means of increasing sampling speed. The diversity of sampling techniques is narrowed to one general algorithm: conditional bit sampling. Conditional bit sampling uses a high-speed uniform random number generator based on feedback shift registers to sample one bit at a time. The probability of a bit being a one in the j-th position of a binary expanded variate is stored in a table of conditional probabilities. A comparison with the pseudorandom number yields a one or zero. The table of conditional probabilities is generated once …

Diaphragm Braced Channel And Z-Section Beams, George Winter, Nuri Celebi, Teoman Peköz

CCFSS Library (1939 - present)

PREFACE Cold-·formed channels and Z-shapes are widely used as purlins supporting roof surfaces which consist of light-gage steel panels or other material. If the panels are interconnected to form diaphragms, they brace the purlins and increase their carrying capcity sizeably. It is the purpose of this investigation to explore this bracing effect and provide tools for its utilization in~design. The author wishes to express his gratitude to Professors George Winter and Teoman Pekoz, Project Directors. Their suggestions, criticism and guidance made this work possible. The research project covered by this report was sponsored at Cornell University by the American Iron …

The Structural Behavior Of Cold-Formed Steel Members With Perforated Elements, Charles S. Davis, Wei-Wen Yu

CCFSS Library (1939 - present)

PREFACE This report was originally a dissertation presented to the Faculty of the Graduate School of the University of Missouri-Rolla in partial fulfillment of the requirements for the Degree of Doctor of Philosophy in Civil Engineering, for conferment in May 1972. The research project described within was sponsored by American Iron and Steel Institute through a Special Engineering Fellowship in the fiscal year 1970-71. The author wishes to thank Dr. Wei-Wen Yu, Associate Professor of Civil Engineering, University of Missouri-Rolla for his invaluable guidance in his joint capacity as the project director and as major advisor of my advisory committee. …

Lowering The Transportation And On Site Labour Costs - Some Proposals, Iraj E. Majzub

International Symposia on Low Cost Housing Problems

No abstract provided.

Suspended Modular Component System, Lawrence C. Abell, Conrad P. Heins Jr.

International Symposia on Low Cost Housing Problems

No abstract provided.

The Sears Eco-System Home, Jack R. Warner, G. Day Ding

International Symposia on Low Cost Housing Problems

No abstract provided.

Housing Design Process And Ekistics -- A Systems Approach, Jawalker K. Sridhar Rho

International Symposia on Low Cost Housing Problems

No abstract provided.

Use Of Pressurized Membranes As A Low-Cost Erection Scheme For Concrete Structures, John W. Leonard

International Symposia on Low Cost Housing Problems

No abstract provided.

The Technology And Management Of Mobile Home Production, Arthur D. Bernhardt

International Symposia on Low Cost Housing Problems

No abstract provided.

Engineering Improvements In Reclaimed Marshland For Housing Project, Carl W. Garbe, Kuei-Wu Tsai

International Symposia on Low Cost Housing Problems

No abstract provided.

Low Cost Housing Is Not Low Standard Housing, N. K. Gandhi

International Symposia on Low Cost Housing Problems

No abstract provided.

The Systems Approach To Lower-Cost Housing, Kenneth G. Jessop

International Symposia on Low Cost Housing Problems

No abstract provided.

The Procurement Process And System Building For Housing, Guy G. Rothenstein

International Symposia on Low Cost Housing Problems

No abstract provided.