Engineering Commons^™

Temperature And Stress Distributions Produced In Long Circular Cylinders Cooled By Emission Of Thermal Radiation, Robert S. Pritchard

Mechanical Engineering ETDs

This study involves the determination of the temperature and stress distributions produced in long circumferentially symmetric circular cylinders cooled by emission of thermal radiation from the lateral surface. Temperature and strain responses obtained from an experimental model are presented for a set of parameters which correspond to the highest strain level which could be accurately determined with the strain gages. These responses are in good agreement with the results obtained by solution of an appropriate mathematical model. Temperature responses obtained from the same model, but having a higher initial temperature, are also presented and compared with analytical results. Reasonably good …

Drag Forces On Magnetically Accelerated Particles, Darrell Winterton Walker

Theses and Dissertations

The object of this investigation was to determine the effect of acceleration on the drag of spheres as it differs from the steady state case. Steady state drag applies to the force acting on a single sphere moving at constant velocity through an infinite, continuous, incompressible, turbulence free fluid. Extensive experimentation has quite thoroughly documented the steady state drag characteristics of spheres. A dimensionless parameter associated with the drag force is sometimes used to correlate drag characteristics.

Turbulent Flow In The Entry Region, Chin-Hsiu Li

Theses and Dissertations

When entering into the subject of turbulent flow, it is essential to understand that the kind of flow with which we deal belongs to a particular class known as shear flow. These types of flow comprise flow fields in which relative velocities have been induced by shear stresses rather than by the action of pressure forces. In pipe flow, when the fluid enters through the well-rounded bell from a reservoir or from the calm open air, a uniform velocity distribution occurs at the pipe entrance. Immediately down stream from the entrance of the pipe, the flow is structured with a …

The Vibration Response Of Laminated Orthotropic Plates, Max E. Waddoups Jr.

Theses and Dissertations

The behavior of anisotropic materials has been the object of much recent research® The high strength to weight ratio needed by aerospace structures has necessitated the use of exotic, composite materials which generally exhibit anisotropic behavior® These materials cannot be fully utilized unless analytical techniques are used which take maximum advantage of their anisotropic behavior.

The Investigation And Design Of A Powered, Single-Man Parawing Aircraft, Calvin J. Merrell

Theses and Dissertations

During the last few years there has been an increasing interest in a high-lift wing configuration known as the flex-wing, or parawing. The parawing consists basically of a flexible membrane such as cloth, attached to two leading edges (or booms) and a keel as shown in Figure 1. At angles of attack (��) greater than the billowing angle (��). the air impinges on the under side of the membrane and forces it into a double-arch shape at each cross-section. When straight leading edges are used, each arch approximates the shape of a conical section. A cylindrical section is obtained by …

Heat Transfer In Shock Boundary Layer Interaction Regions, Rex W. Shumway

Theses and Dissertations

The interest in aerodynamic heating problems has been increasing rapidly in the last decade. This interest is no longer concentrated on the heating of simple shapes for which adequate heat transfer theory has been developed« Because of the increasing Mach number ranges of aircraft, the need for information on the aerodynamic heating of various components has become imperative. Only when the magnitude of the problem has been exposed can the design for reducing the severity of local heating be optimized. Definition of these problems is of interest, not only because of the flow phenomena, but because of possible design limitations …

Liquid Particle Interaction With A Normal Shock Wave, Victor George Forsnes

Theses and Dissertations

The atomization of a liquid by an air stream has been an item of much concern in the past, and there have been numerous experimental studies of the process made in an effort to correlate liquid and air- stream physical properties into a general model which will predict the degree of and the time required for atomization for a given physical situation. The breakup of liquid drops, a major portion of the atomization process, finds application in the field of meteorology, where the formation, breakup, and shape of raindrops is an item of much concern; in the field of internal …

Residual Stresses And The Bauschinger Effect, Raymond M. Huebner

Theses and Dissertations

Within the last ten years there has been much interest in the field of elasto-plastic behavior of engineering materials. Hie recent popularity of the low-cost light-weight plastically designed structures has added a great deal of impetus to this interest. This thesis deals with one of the aspects of elasto-plastic behavior, namely, the distribution of the residual stresses in a simple member which has been plastically deformed in tension and/or compression,. In particular, an attempt has been made to relate these residual stresses to the well-known but little understood Bauschinger effect.

Residual Stress Distribution Changes During Dynamic Unidirectional Tensile Loading, Henry Swan Todd

Theses and Dissertations

In recent years there has been much engineering effort channeled toward obtaining higher strength, lower weight and cost product designs. In pursuit of this goal some carefully designed and tested parts have catastrophically failed after a long history of repeated successful service, even though the load at the time of failure was no higher than the part had repeatedly carried previously. These mechanical failures are commonly classified as fatigue failures.

Cavity Effect In A Pressure Bar, Kenneth B. Simmons

Mechanical Engineering ETDs

The investigation deals with certain aspects of wave propagation in a rod containing a penny-shaped cavity, particularly fracture related to the presence of the cavity. When a rod containing a cavity is subjected to a compressive stress pulse, part of the pulse is transmitted past the cavity and part is reflected. When the end of the rod is free, the cavity is subjected to a reflected tensile pulse which, if strong enough, can cause fracture. The existence of the cavity tends to weaken the rod since there is a reduction in the cross-sectional area and a stress concentration effect. Epoxy …

Instrumentation Of A Diesel Engine For Measuring Cylinder Head Temperature, And Pressure At Various Crank Angles, Raman A. Patel

Masters Theses

"In this investigation, an attempt has been made to measure the instantaneous pressures in the cylinder and the transient temperatures of cylinder head versus crank angle in a Diesel engine. A strain-gage pressure transducer and a sensitive surface thermocouple were used. The pressure transducer was practically free from temperature influence and strain effects caused by installation. It had a greatly reduced sensitivity to vibrations compared with other available types of pressure transducers. The thermocouple had a very short response time. A device enabling very accurate measurement of crank-angle was constructed. Appropriate quantities were displayed on the screen of an oscilloscope …

Transient Temperature Distribution In A Finite Cylinder And An Infinite Cylinder Subjected To Some Boundary Conditions, Harng-Sen Huang

Masters Theses

"This thesis is concerned with the theoretical heat transfer analysis of solid cylinders. The first problem considered is the transient temperature distribution in a finite cylinder. This cylinder has a uniform initial temperature and a uniform constant surrounding temperature. This case is solved by the separation of variables. Combining the charts for the infinite cylinder and the charts for the infinite plate one can determine the solution to this case easily. If a uniform constant surface temperature is prescribed instead of a surrounding temperature, the solution can be obtained from the previous one by charging the Nusselt number to infinity. …

The Development And Evaluation Of An Experimental Technique To Determine Stress Distribution In Uniformly Loaded Flat Plates, James William Walker

Masters Theses

"This thesis reports and evaluates an experimental technique that was developed to determine and monitor the stresses in a simply supported, uniformly loaded circular plate. Deflections are less than half the thickness of the plate. The application of the developed technique to plates whose integrity has been compromised with holes in various locations is discussed.

Resistance strain gages were used to determine experimentally the stresses in a simply supported, uniformly loaded circular plate with and without a concentric hole. The accuracy of the experimental results was established to be within approximately six percent of theoretical.

Proper application of the experimental …

Cylinder-Head Surface Temperature And Maximum Pressure In A Diesel Engine, Jayant M. Patel

Masters Theses

"This report presents the result of an experimental investigation on the effect of 1) fuel consumption in a diesel engine on the mean cylinder-head surface temperature 2) engine speed and load on the maximum cylinder pressure.

A fast-response thermocouple was fixed in the cylinder head and temperatures were measured for various load and speed conditions. An attempt was made to record a transient surface temperature versus crank-angle diagram. Some doubt as to the reliability of this recording may arise because of the very small amount of time lag in the thermocouple action. This is immaterial to the subject of this …

Determination Of The Temperature Distribution Of The Ionized Portion Of The Jet From A Vortex Stabilized Plasma Generator Operating On Argon, G. Douglas Schellman

Masters Theses

"The interim thesis deals with the determination of the temperature distribution of a plasma jet operating on argon. It is the purpose of this thesis to present in detail the experimental process used and make a correlation of the experimental and theoretical results.

A copper enclosure was placed around the protruding flame, and the embedded thermocouple readings were taken and recorded. A stagnation temperature probe was inserted in the enclosure and moved both axially and transversely toward the flame taking readings at each pre-chosen interval. The exit temperature of the jet was obtained from a total energy balance.

From the …

The Design And Construction Of A Shock Tube Facility, William Adolph Crede

Masters Theses

"It is the object of this thesis to give an account of the considerations necessary to design, construct, and operate a shock tube facility.

The primary purpose of the facility was to provide a means to study high strength shock waves in physics, chemistry, and aerodynamic applications.

Preliminary designs were undertaken to determine the basic dimensions and related capabilities. Final design, construction and testing of the tube itself was performed by Nooter Corporation in St. Louis, Missouri. Preliminary designs agreed rather closely with final construction.

Experimental testing was confined to the successful operation of all the various components of the …

Optimization Of Flywheel Design For Internal Combustion Engines, Dady Jal Patel

Masters Theses

"A new approach to the problem of flywheel design has been developed, thus eliminating some of the problems of conventional design. The term flywheel design, in this thesis, refers to the determination of the flywheel inertia (mass moment of inertia) only. Two versatile computer programs were set up to obtain the flywheel inertia and the turning moment diagram for a large variety of internal combustion engines, and use was made of these programs to optimize the inertia of the flywheel with respect to speed. As an illustration the data of a 1960 Corvair engine were selected, and the results obtained …

The Eccentric Orifice As A Flow Measuring Device In Small Diameter Pipes, James E. Casale

Masters Theses

"This thesis reports and evaluates the use of an eccentrically placed orifice as a flow measuring device in small pipe sizes. The orifice is placed in a concentric location and moved to increasingly eccentric locations until full eccentricity is reached. At full eccentricity the circumference of the orifice is tangent to the circumference of the pipe. The effects of increasing eccentricity are evaluated for four orifices...Flow coefficients for the orifices in different locations are plotted against Reynolds numbers. The eccentric orifice is a reliable, accurate flow measuring device for metering or controlling the flow of fluids. Design criteria can be …

Application Of The Photoelastic Coating Method To Evaluate The Stress Distribution On The External Surface Of The Cap Of An Electrical Insulator, Harijeetsinh Jagtiani

Masters Theses

"The Photoelastic Coating Method was applied to find the surface stresses on the cap of an electrical insulator. The strain distribution was observed and photographed. This color photograph indicated a visible geography of the maximum shear strain distribution in the region of the insulator where the birefringent plastic was bonded with a reflective cement. The Oblique Incidence technique was used to determine the principal stresses from the maximum shear strain (or the principal strain difference) readings, obtained from Normal Incidence. The critical cross-section of the insulator head was optically located, giving an initiative for the re-design of the insulator cap. …

A Study Of Radiation Heat Transfer In Rectangular Ducts And Enclosures, Jenn-Wuu Ou

Masters Theses

"The purpose of this study is to determine the radiant heat transfer in rectangular configurations and construct a general computer program. Two specific cases are studied in this work. The first case is a rectangular duct with openings at each end. The duct is separated into two sections which are called the source and the sink respectively. A linear temperature profile is imposed on the source section. The energy loss of both the source and the sink is investigated. The second case is a complete rectangular enclosure. The two end plates are called the source and the sink respectively. A …

Free Convection Heat Transfer From An Inclined Heated Flat Plate In Air, Shu Chien Yung

Masters Theses

"An experimental investigation has been performed to determine the free convection heat transfer from a heated flat plate in air moved from the vertical position through three inclined positions to the horizontal position. The hot surface of the plate was facing downward for the horizontal and three inclined positions. Tests were performed at plate surface temperatures from 120°F up to 404°F. Data for the plate surface temperature at about 165°F with the plate in the vertical position agrees very well with previous experimental work. This same data was used to determine a new parameter, introduced into the Pholhausen free convection …

Temperature Distribution In Thermal Boundary Layers (In Free Convection) Using A Modified Schlieren Method, Philip Ling Chen

Masters Theses

"A simple optical apparatus, the Schlieren interferometer, was constructed for the quantitative investigation of free convection heat transfer from solid bodies. The photographic results, checked by using thermocouples, were used in evaluating the temperature distribution, the key to the solution of these problems. Interpretation of the photographic results was made using the simple calculation for the conventional interferogram and the Dale-Gladstone law. Although the experiments were limited to a heated flat plate and a heated wire, two dimensional test pieces of irregular configuration can be investigated by the same apparatus with simple modifications. The photographs of the conventional Schlieren, the …

Turbulence In Journal Bearings, Kashyap R. Mehta

Masters Theses

"In this investigation, an experimental study was performed on a journal bearing under laminar and turbulent flow conditions. Using relationships for friction factor developed previously by other investigators a comparison was made with results of this present investigation. Since the flow changes from laminar to turbulent with a change in speed of rotation, curves for friction factor as a function of speed were plotted. Various attempts to make the recording and measuring systems more sensitive were also made and are discussed in this thesis"--Abstract, page ii.

A Study Of The Non-Newtonian Turbulent Fluid Flow Through An Annulus, Yogesh R. Parikh

Masters Theses

"This investigation is concerned with the study of non-Newtonian flow through an annulus. The experimental analysis of incompressible non-Newtonian fluids in a long cylindrical annulus of radius ratio 0.375 was studied in the turbulent region. Different types of non-Newtonian fluids were used to procure flow behaviour for the annulus.
The effect of increasing flow rate of the non-Newtonian fluids was evaluated by gathering pressure drop data across the annulus using a differential manometer. The power-law model is used in this study to characterize the non-Newtonian flow. The parameters of the power-law model were evaluated by gathering viscometric data on a …

Heat Transfer Coefficients Across Bonds And Contacts, Eugene Charles Fadler

Masters Theses

"The purpose of this investigation was to experimentally determine heat transfer coefficients across interfaces, including the effects of the thermal conductivity of the adherends, the hardness of the adherends, the bond thickness, and the type of adhesive.

Aluminum alloy, steel, copper, and extruded nylon rods were used as adherends; all 1.875 inches diameter and 8 inches long. Each was cut radially at its midpoint and faced off to the desired surface finish. Bare interface tests were conducted before the adherends were bonded together. The adhesives used were high grade silica refractory cement, two-part epoxy resin adhesive, and thermosetting synthetic rubber-phenolic …

The Effect Of Lubri-Coolant Application At The Tool-Chip Interface On Tool Forces, Bomi Ardeshir Hathikhanavala

Masters Theses

"The purpose of this experiment was to determine the effectiveness of a lubri-coolant directed in such a way that it impinged just below the chip at the tool-chip interface in an orthogonal cutting process. This was compared to the conventional method of flooding lubri-coolant around the tool-chip area ... The results obtained show that the forces required to cut a material were less if the lubri-coolant was directed on the tool-chip interface when larger values of feed and depth of cut were used, and that with smaller values of feed and depth of cut, the method of flooding was equal …

Analysis Of The Flow Characteristics Through A Water Pressure Regulator, Anthony Lee Jatcko

Masters Theses

"This thesis presents an analysis of the flow characteristics through a water pressure regulator. Characteristic curves of the relationship between pressure drop through the regulator and flow through the regulator are developed. To further analyze these relationships, a least squares computer analysis was used to develop equations to fit these curves. An investigation into the modes of dissipating pressure energy in this type of regulator tends to indicate that a significant portion of the energy is lost through viscous shearing action in the area of high turbulence. The aforementioned characteristic curves also showed definite critical pressure points in the form …

An Apparatus To Measure Capillary Jet Thrusts And The Evaluation Of Normal Stresses In Fluids, Charles Donald Green

Masters Theses

"The purpose of this work was to design, construct and calibrate simple, inexpensive apparatus which could be used to measure the normal stresses and tangential shear stresses of a fluid. For normal stress measurements, the capillary jet thrust principle was selected. A standard analytical balance was modified so that capillary tubes could be fitted on it horizontally. It was designed so that the thrust produced by a jet of fluid from the tube caused a deviation from the zero balance position. The weights needed to rezero the balance gave a measure of the thrust"--Summary, page 1.

A Photoelastic Study Of The Effect Of Certain Geometric Variables On The Plane Stress Distribution In An Electrical Insulator Body, Richard L. Pendleton

Masters Theses

"Photoelastic models were used to indicate stress patterns in various geometrically designed shapes. Each model represented a two-dimensional cross-section of the interior portion of an axially symmetrical porcelain electrical insulator. Five different loading pins were combined with three loading heads to produce eleven models. The maximum stress in each model was determined using a photoelastic method of stress analysis. An attempt was made to select the best structural design to be used in an electrical insulator. The test results indicate that the most desirable stress distribution is obtained using a single step loading pin and that the loading head angle …

The Design And Construction Of An Instrument For Calibrating Accelerometers, Richard Rabenau

Masters Theses

"The purpose of this work was to design and construct a facility to calibrate accelerometers. A ceramic piezoelectric shaker and modified Michelson interferometer together with necessary electronic equipment were used. The system produced accurate and stable acceleration at five discrete points from 1,000 to 5,000 cycles per second. the maximum calibration levels were approximately 50 g's"--Abstract, page ii.