Digital Commons Network^™

A Triangular Element For Numerical Solutions Of Axisymmetric Conduction Problems In Cylindrical Coordinates, Prafulla Chandra Mahata

Masters Theses

"The triangular element is one of the many suitable elements which are used in finite difference methods as applied to conduction heat transfer. Such elements find many applications in conduction problems in Cartesian coordinates. This work proposes a new triangular element for axisymmetric conduction problems in cylindrical coordinates. The validity and workability of the networks formed by the proposed triangular elements are strengthened by selected examples. The work is completed by the application of the triangular element to an industrial problem having irregular boundaries. The results are compared with the solution obtained by the finite element method"--Abstract, page ii.

Use Of The Turbulence Kinetic Energy Equation In Analyzing Turbulent Near Wakes, James Edward Auiler

Doctoral Dissertations

"A general method is presented for analyzing turbulent flow fields in the near wake regions of two-dimensional and axisymmetric bodies. The governing partial differential equations of continuity, momentum and turbulence kinetic energy are expressed in elliptic form in terms of the dependent variables stream function, vorticity and turbulence kinetic energy. An iterative finite-difference technique is used to solve the governing equations simultaneously. Numerical solutions are obtained for the following physical problems: 1. Laminar near wake: Only stream function and vorticity are considered for laminar flow. Solutions are compared with available analytical results for uniform flow over a sphere. 2. Turbulent …

An Investigation Of Subsequent Yield Phenomena, Joseph George Hoeg

Doctoral Dissertations

"A method utilizing high pressure fluid environments is described whereby a three-dimensional subsequent yield surface was determined for 304 stainless steel. Cylindrical parent specimens of this material were prestrained in axial compression under fluid pressure and then small sub-specimens were sectioned from these parent specimens. Finite element techniques were used to optimize the parent specimen size so that a zone of uniform axial stress would result during the prestraining. Longitudinal strains in this zone were monitored during the prestraining and the sub-specimens were cut from this region in a manner that did not allow the machining to appreciably affect the …

An Investigation Of A Bistable Oscillator Used In A Phase Modulated Control Circuit, Yu-Fang Yen

Masters Theses

"A primary component in the investigation of phase modulated control systems is bistable oscillator which converts a constant oscillation signal to control the system. The oscillator is feedback type that utilizes a feedback capacitance and resistance in each feedback path to change its frequency. The theoretical behavior of bistable oscillator was investigated and the non-dimensional results were set for convenience in determining the oscillation period. The control circuit which based on the oscillator was also presented a form of suitable circuit for direct application to practical control problems"--Abstract, page ii.

Development Of An Elastic-Plastic Finite Element Program With The Initial Strain Approach, Vernon Dale Allen

Masters Theses

"A finite element method is presented for solution of plane stress and axisymmetric elastic-plastic problems employing the method of successive elastic solutions with the initial strain approach. The problem of nonconvergence of the initial strain approach for perfectly plastic problems was eliminated by expressing the Prandtl-Ruess equations entirely in terms of strain. Two examples are presented to demonstrate the validity of the method"--Abstract, page ii.

An Approximate Model For The Static Operation Of A Fluidic Amplifier Employing Axisymmetric Jets, Richard T. Johnson

Mechanical and Aerospace Engineering Faculty Research & Creative Works

An approximate mathematical model for the static, no-load (blocked receiver) operation of a fluidic amplifier employing axisymmetric jets is developed. The amplifier is similar in concept to the three-terminal modulator developed by the Johnson Service Co. The approach used in developing the model assumes that the complex flow phenomena can be represented by the combination of several elementary flow problems. The model employs the concept of an equivalent power nozzle in describing downstream flow with a control signal present. Experimental results are presented to justify assumptions and evaluate parameters. © 1971 by ASME.

A Study Of A Nitrogen Heat Pipe, Jay Dudheker

Masters Theses

"An experimental heat pipe, 33.25 inches long and 0.75 inches in diameter, with modacrylic fiber wick and liquid nitrogen as its working fluid was constructed to study the operating characteristics of a cryogenic heat pipe. The effective thermal conductivity and the axial temperature distribution were determined for various levels of power input. The effect of inclination angle on the above parameters was also measured"--Abstract, page ii.

An Experimental Determination Of The Effect Of The Axisymmetric Turbulent Wake On The Pressure Distribution On A Sphere, Martin Gardner Bowin

Masters Theses

"A study of the effect of the turbulent wake of a water drop on the motion of a smaller droplet is essential in order to gain an understanding of the behavior associated with the collision coalescence phenomena. The use of spheres of macroscopic size proves to be a valuable method in observing these effects. This experimental investigation centers on (1) a check on the validity of the instrumented sphere as a device to measure normal static pressure, and (2) the study of the effect of the turbulent wake of the test model sphere upon the instrumented sphere. Measurements were made …

A Study Of Radiative Heat Transfer From A Spherical Layer, Hakimuddin Kalimuddin Khalil

Masters Theses

"The problem of radiative heat transfer from a spherical layer of absorbing-emitting gas has been studied. First, the medium is assumed to be gray and then nongray. A thorough survey of literature from fields other than heat transfer, such as astrophysics and neutron transport has been made to stimulate further interest in this important area. To gain some insight into the effect of various parameters on the heat transfer, simple physical situations involving isothermal medium are considered. Comparison of the results obtained for the flux from the spherical and planar layers reveal that the curvature becomes increasingly important as the …

Laminar Heat Transfer For Small Prandtl Number Fluids Including Step Change In Wall Temperature, Shiny Ting

Masters Theses

"The object of this investigation is to provide a simple means of determining the heat transfer from a flat plate which has an unheated leading length x₀. The case of steady, two-dimensional, laminar flow of an incompressible fluid with a Prandtl number of less than one is considered. Since there exists an unheated length and the Prandtl number of the fluid is less than one, the thermal boundary layer intersects the flow boundary layer. Thus, the solution of the problem divides into two regions. In this study, the problem is solved analytically by employing the energy integral equation. The temperature …

Basic Instrumentation Of A Three-Zone Convection Coater Dryer For Calculation Of Heat And Mass Balances, Byron H. Mckinstry

Masters Theses

No abstract provided.

The Design Of A Laser Doppler Velocimeter, Marlo R. Anderson

Theses and Dissertations

A relatively new method of measuring local velocity in a fluid stream has been devised which eliminates some of the inherent problems of the traditional methods. This method senses the Doppler shift of light scattered from a laser beam incident on particles suspended in the fluid. The Doppler shift is proportional to the particles (or fluid) velocity. This new technique has several distinct advantages over the more traditional methods of velocity measurement.

A Numerical Solution To The Problem Of Rotation Near The Ground, David D. Chen

Mechanical & Aerospace Engineering Theses & Dissertations

No abstract.

Theoretical And Experimental Evaluation Of Cardiac State Utilizing Indicator Dilution Methods For Nonuniform Ventricular Mixing, Stanley Myron Welland

Dissertations

This research is directed toward the development and application of a new approach to the evaluation of cardiac work to diagnose cardiac state. A procedure has been developed for calculating the work performed on the fluid by the left ventricle during the heartbeat. The procedure involves the continuous direct measurement of ventricular fluid mixture temperature during and following the controlled injection, through a catheter, of a known volume of cold saline into the left ventricle. The measured mixture temperatures are used to calculate continuous ventricular volumes during the systolic and diastolic functions of the heartbeat. Plotting measured ventricular pressure versus …

On The Classification Of The Solution Space Of Linear Anisotropic Elasticity, Richard Clement Carman

Dissertations

A method is developed within the framework of Synge's function-space interpretation of problems in linear elasticity which allows the consideration of solutions to problems for anisotropic media in terms of the solutions of a corresponding isotropic problem and corresponding simpler anisotropic problems. The isotropic solution and simpler anisotropic solutions establish points in each of the statically and kinematically admissible spaces for the anisotropic problem. The established points are used to define sets of vectors in the statically and kinematically admissible spaces. The linear independence of these vectors can then be determined by a pair of criteria developed in this work. …

A Feasibility Study Of The Application Of Bondgraph Modeling And Computerized Nonlinear Model Parameter Identification Techniques To The Cardiovascular System, Randall L. Taylor

Theses and Dissertations

Recent years have witnessed an increasing trend for people in the medical and engineering professions to couple their talents in a more united effort to better understand the functioning of the human body. This union of technologies has meant the introduction of new viewpoints and techniques in the field of physiological research. The engineers' basic tool, mathematical modeling, has perhaps been one of the most noticeable additions. There has been a significant amount of work done in recent years along these lines of deriving mathematical models to express the functioning of a subsystem of the body, and then, using analog, …

An Investigation Of A Computer Technique For Determining The Characteristic Parameters Of A Viscoelastic Model With Hysteresis Effects From Transient Experimental Data, Stephen Jack Clark

Theses and Dissertations

The object of this work was to develop a computer technique for determining the characteristic parameters of spring-mass system with hysteresis effects from transient experimental data. The technique was intended to be utilized to determine the parameters of models of systems where complex geometry and rate dependent properties would make a determination of the model parameters most difficult, and where the parameters typically obtained from static test would not characterize the rate dependent properties accurately.

Non-Linear Analysis Of Electrocardiogram Tracings In Detection Of Occult Coronary Artery Disease, Joseph Robert Levitt

Dissertations

The general problem of identifying significant characteristics of a system by analyzing the properties of a signal emitted by that system is common to many disciplines, biological as well as physical. In general, achievement of a satisfactory solution depends on the capability of assigning membership of candidate signals to one of a number of mutually exclusive categories:

In this study, a new technique of processing the standard electrocardiograms from human subjects has been developed. This technique employs a set of non-linear transformations which enable the assignment of electrocardiograms into one of two Mutually exclusive categories. The first category is that …

Dynamic Stress Concentrations About An Epilliptical Discontinuity In An Elastic Solid, Kenneth Roy Schroll

Dissertations

The redistribution of dynamic stresses caused by the presence of an elliptical discontinuity in an infinite isotropic homogeneous elastic solid is examined. The solutions are obtained for the special cases of the rigid immovable inclusion and the vacuous cavity inclusion, and numerical results are presented.

The solutions to the wave equations in elliptical coordinates are expressed in series of the elliptical geometry eigenfunctions. Application of the boundary conditions, vanishing displacements for the rigid immovable inclusion and vanishing stresses for the cavity inclusion, yields in each case two infinite sets of linear algebraic equations for the expansion coefficients of the series …

The Computer Evaluation Of The Natural Frequencies Of Vibrating Circular Plates With Free, Fixed And Simply Supported Edges, Thomas Michael Juliano

Theses

The natural frequencies of the transverse vibration of a thin, isotropic, circular plate with free, clamped, and simply supported edge conditions were studied extensively. The frequency equation for each edge condition was derived from the classical partial differential equation of plate vibration. These equations, which are in terms of Bessel functions, were then solved numerically to find the natural frequencies. Since the accuracy of the Bessel function values is very important in evaluating these frequencies, a comprehensive digital computer program was devised to calculate these values to eleven digit accuracy. In this Bessel function program four different methods were required …

Test 1044: Allis-Chalmers Crop Hustler 185 Diesel, Nebraska Tractor Test Lab

Nebraska Tractor Tests

EXPLANATION OF TEST REPORT GENERAL CONDITIONS East tractor is a production model equipped for common usage. Power consuming accessories can be disconnected only when it is convenient for the operator to do so in practice. Additional weight can be added as ballast if the manufacturer regularly supplies it for sale. The static tire loads and the inflation pressures muse conform to recommendations in the Tire Standards published by the Society of Automotive Engineers. PREPARATION FOR PERFORMANCE RUNS The engine crank case is drained and refilled with a measured amount of new oil conforming to specifications in the operator’s manual. The …

Test 1043: Allis-Chalmers Crop Hustler 175 Diesel, Nebraska Tractor Test Lab

Nebraska Tractor Tests

EXPLANATION OF TEST REPORT GENERAL CONDITIONS East tractor is a production model equipped for common usage. Power consuming accessories can be disconnected only when it is convenient for the operator to do so in practice. Additional weight can be added as ballast if the manufacturer regularly supplies it for sale. The static tire loads and the inflation pressures muse conform to recommendations in the Tire Standards published by the Society of Automotive Engineers. PREPARATION FOR PERFORMANCE RUNS The engine crank case is drained and refilled with a measured amount of new oil conforming to specifications in the operator’s manual. The …

Test 1042: Oliver 1655, Nebraska Tractor Test Lab

Nebraska Tractor Tests

No abstract provided.

Test 1040: Oliver 1855 Diesel, Nebraska Tractor Test Lab

Nebraska Tractor Tests

No abstract provided.

Test 1041: Oliver 1655 Diesel, Nebraska Tractor Test Lab

Nebraska Tractor Tests

No abstract provided.

Test 1038: Case 970 Power Shift Gasoline, Nebraska Tractor Test Lab

Nebraska Tractor Tests

EXPLANATION OF TEST REPORT GENERAL CONDITIONS East tractor is a production model equipped for common usage. Power consuming accessories can be disconnected only when it is convenient for the operator to do so in practice. Additional weight can be added as ballast if the manufacturer regularly supplies it for sale. The static tire loads and the inflation pressures muse conform to recommendations in the Tire Standards published by the Society of Automotive Engineers. PREPARATION FOR PERFORMANCE RUNS The engine crank case is drained and refilled with a measured amount of new oil conforming to specifications in the operator’s manual. The …

Test 1037: Case 970 Power Shift Diesel, Nebraska Tractor Test Lab

Nebraska Tractor Tests

EXPLANATION OF TEST REPORT GENERAL CONDITIONS East tractor is a production model equipped for common usage. Power consuming accessories can be disconnected only when it is convenient for the operator to do so in practice. Additional weight can be added as ballast if the manufacturer regularly supplies it for sale. The static tire loads and the inflation pressures muse conform to recommendations in the Tire Standards published by the Society of Automotive Engineers. PREPARATION FOR PERFORMANCE RUNS The engine crank case is drained and refilled with a measured amount of new oil conforming to specifications in the operator’s manual. The …

Test 1039: Case 970 Manual Gasoline, Nebraska Tractor Test Lab

Nebraska Tractor Tests

EXPLANATION OF TEST REPORT GENERAL CONDITIONS East tractor is a production model equipped for common usage. Power consuming accessories can be disconnected only when it is convenient for the operator to do so in practice. Additional weight can be added as ballast if the manufacturer regularly supplies it for sale. The static tire loads and the inflation pressures muse conform to recommendations in the Tire Standards published by the Society of Automotive Engineers. PREPARATION FOR PERFORMANCE RUNS The engine crank case is drained and refilled with a measured amount of new oil conforming to specifications in the operator’s manual. The …

Test 1034: Case 970 Manual Diesel, Nebraska Tractor Test Lab

Nebraska Tractor Tests

EXPLANATION OF TEST REPORT GENERAL CONDITIONS East tractor is a production model equipped for common usage. Power consuming accessories can be disconnected only when it is convenient for the operator to do so in practice. Additional weight can be added as ballast if the manufacturer regularly supplies it for sale. The static tire loads and the inflation pressures muse conform to recommendations in the Tire Standards published by the Society of Automotive Engineers. PREPARATION FOR PERFORMANCE RUNS The engine crank case is drained and refilled with a measured amount of new oil conforming to specifications in the operator’s manual. The …

Test 1035: Case 1070 Manual Diesel (Also Case 1090 Manual), Nebraska Tractor Test Lab

Nebraska Tractor Tests

EXPLANATION OF TEST REPORT GENERAL CONDITIONS East tractor is a production model equipped for common usage. Power consuming accessories can be disconnected only when it is convenient for the operator to do so in practice. Additional weight can be added as ballast if the manufacturer regularly supplies it for sale. The static tire loads and the inflation pressures muse conform to recommendations in the Tire Standards published by the Society of Automotive Engineers. PREPARATION FOR PERFORMANCE RUNS The engine crank case is drained and refilled with a measured amount of new oil conforming to specifications in the operator’s manual. The …