Mechanical Engineering Commons^™

Development Of A Simple Bar Method Thermal Conductivity Test, V. J. Flanigan

Masters Theses

"A linear flow bar method type apparatus was set up for finding thermal conductivities by comparison techniques. Comparison technique consist of using a standard specimen where the thermal conductivity is known and comparing it to the unknown specimens to find their conductivity. Apparatus of this type usually uses thermocouples for the required temperature measurements, but thermistors were used in this experiment. The thermistors used required calibration to measure accurate temperatures and this was accomplished by using the known temperatures of the changes of state of some common materials. Five alloys were used to evaluate the method: SAE 1020 steel, gray …

Transpiration Cooling Of A Porous Plate, Stephan A. Sayegh

Masters Theses

"Transpiration cooling has long been known as an effective way of removing heat from porous materials. This thesis is a new approach to one of the problems of transpiration cooling in the steady state.

The specific problem considered here is that of a uniform porous plate through which a liquid is forced. This liquid vaporizes at a short distance from the surface through which it is forced and leaves the porous plate at the other surface which is exposed to hot gases. It also protects the hot surface by forming an insulating layer between that surface and the hot gases. …

Experimental Stress Analysis Of Bolts In A Flange Coupling, Vijay Rastogi

Masters Theses

"In this investigation an attempt has been made to determine simple formulae leading to a better, more useful and much safer design of flange coupling bolts. The bolts were tested under tensile loading and bending and hence the results obtained apply for bolts under these modes of loading only.

The behavior of flange bolts under different initial tightening torques was studied by measuring strains in a bolt on which strain gages had been attached* . From this, the load producing separation of flanges, under different tightening torques, was determined and used in deriving formulae for prediction of the load for …

A Correlation Of Heat Transfer Coefficients Using An Induction Heater, Charles Maurice Martin

Masters Theses

"This thesis represents a study of the following problems. (1) Determination of techniques and equipment which would give satisfactory correlation of experimental heat transfer coefficients with those obtained from acceptable heat transfer equations when using an induction heater as the heat source. (2) Determination of depth of energy deposition in a thick-walled tube due to induction heating.

Techniques were developed that gave a correlation between experimental and calculated coefficients that were within -5% for minimum flow and +8% for maximum flow.

Because of difficulties in positioning thermocouples, the depth of energy deposition could not be accurately determined. However, two surface …

A Comparison Of The Load Carrying Characteristics Of Hydrostatic Thrust Bearing Using Monatomic, Diatomic, And Triatomic Gases, Joseph C. Pigott

Masters Theses

"The purpose of this investigation is to compare the load carrying characteristics of gases with different ratios of specific heat. The design, construction, and operation of an apparatus for testing and comparing the load carrying characteristics of gases are described. Several monatomic, diatomic, and triatomic gases were tested and the results evaluated and compared. The data are tabulated and displayed in a series of curves.

It was found that the monatomic gases exhibit a greater clearance for a given load and a greater total load carrying capacity than the diatomic gases which in turn have a greater clearance and total …

The Analysis, Construction, And Calibration Of An Electronic Vibrations Amplifier, Jimmie D. Howard

Masters Theses

"Vibrations analysis necessitates having a device capable of performing some initial phase of detection. The vibration amplifier presented in this thesis performs such an initial aid to analysis by detecting amplitudes of vibrations of varying magnitudes and frequencies. This is accomplished by utilizing a Piezoelectric crystal vibration pickup to obtain an acceleration wave form. Two operational amplifiers perform integrations of the acceleration to obtain displacement. A calibrated meter within the device provides a method of determining magnitudes of displacement. Recording instruments such as the Brush recorder or an oscilloscope may also be used"--Abstract, page ii.

Effect Of Boundary Layer Control, Through Spiral Cuts, On The Film Coefficient Of Convective Heat Transfer, Nicholas W. Barre

Masters Theses

"This thesis is experimental investigation into the possibility of obtaining an increase in the forced convection heat transfer coefficient for a pipe by passing the fluid through a narrow spiral cut in the pipe.

Different spiral pipes with pitches of two, four, eight, ten, sixteen, and twenty inches were used; however, the width of the spiral cut remained unchanged at 3/16 of an inch. Several mass flow rates for water were used up to a maximum of 1536 lbs/hr for each run.

One of the objectives was to find which pitch would give the highest heat transfer rate for a …

Preliminary Study Of An Optimum Vibration Absorber For A Multi-Mass System With Multiple Excitation, John Raymond Burrows

Masters Theses

"The object of this thesis is to demonstrate, by the use of a modern digital computer, a fast, efficient method to eliminate or minimize undesirable stress conditions in a multimass vibrating system with multiple excitation. The condition desired is obtained by the addition of an optimum tuned and damped dynamic vibration absorber, for one critical speed only.

Maximum stress is the criteria used for design here and not amplitude as has been used previously by all other authors.

This solution requires the applied torque to be reevaluated as an average torque and a number of half integer harmonics. This method …

Transpiration Cooling Of A Plane Porous Plate, Raymond George Posgay

Masters Theses

"The transient temperatures were determined in a porous plate for one dimensional heat flow and one dimensional counter coolant flow. One surface of the porous plate was heated by a hot gas by convective heat transfer. A general discussion of the problem is considered and the procedure described for working all such problems dealing with transpiration cooling.

The solution of such problems is illustrated by two examples employing a ceramic plate one inch thick and cooled by a uniform flow of air in a direction counter to the flow of heat, while one surface of the ceramic plate was heated …

An Analog Method For The Determination Of The Deflection Of Beams Resting On End Supports And Design Of An Automatic Programming Device, Paul C. Jackson Jr.

Masters Theses

"This investigation shows that beam problems can be solved easily and accurately with an analog computer. Two problems were solved as to their shear, moment, slope and deflection along the length of the beam and the graphs drawn by the analog computer were compared with calculated values. Very little difference was found between them.

An electronic programmer was built to aid in handling beam problems as they were being run on the computer. This was capable of putting into the computer bits of data at specified intervals of time. The programmer proved reliable and repeatable once it was adjusted to …

Transient Temperature Distribution In Solid Sphere Subjected To Radiation Heat Exchange, William H. Stocklin

Masters Theses

"The author believes that numerical analysis is the most feasible approach to calculating the transient temperature distribution in a solid sphere subjected to various surface conditions; heat flow within the sphere is radial.

Numerical analysis is employed to arrive at a series of equations for calculating the transient temperature at selected points of a solid sphere. A study is made to determine a method for calculating temperatures with these equations; a computing device is found to be the most practical method for this purpose. The equations for temperatures at internal points of the solid sphere are general.

The equations have …

Transpiration Cooling, Herbert S. Brahinsky

Masters Theses

"In the investigation of the problem, it is shown that the process of transpiration cooling is an effective method of cooling. This process may be applied to heat screens or heat shields, as was done in the sample problems worked out here. A porous plate with coolant flowing counter to the flow of heat was used.

The plate temperature is determined by the amount of heat flux, coolant flow, thermal conductivity of the material used as a plate, the specific heat of the fluid, the specific heat of the plate material, the density of the plate material and its porosity. …

An Evaluation Of The Addition Of Magnesium Carbonate To Promote Collapsibility In Sodium Silicate Bonded Cores, Wilfred Durairajan Paul

Masters Theses

"Cores are separate sand masses included in the mold to accomplish shapes that would be impossible or difficult to obtain with a normal simple mold cavity.

For example a core made for a pipe casting is expected, first, to support itself when placed in the mold and also withstand handling at room temperature. Second, it should withstand, for a short time, the high temperature of molten metal. Last, it should possess the ability, to completely lose its strength just after the metal around it has completely solidified.

Until recently cores for castings were made using oil bonded sands, with an …

Transient Temperature Distribution In An Infinite Plate Subjected To Convection And Radiation Heat Exchange, Billy W. Marshall

Masters Theses

"The desired result of this paper is a method of calculating transient temperatures in an infinite plate. The resulting equations are general to the extent possible for aerodynamic heating and radiation boundary conditions. The possible methods of calculation were investigated, and it was felt that a numerical analysis presented the most feasible approach.

Numerical analysis was employed to arrive at a series of equations for calculating the temperatures at selected positions in an infinite plate. A study was then made to determine a method of solving these equations by means of some high speed computing device.

The equations were adapted …

Temperature Distribution In An Infinite Plate As A Function Of The Input Heat Flux, George Franklin Wright

Masters Theses

"It is the purpose of this thesis to investigate the effects of a variable input heat flux impinging equally on both sides, on the temperature distribution within an infinite plate. An infinite plate may be defined as one in which the dimensions are infinite in two directions and finite in thickness. For practical purposes such a plate could be thought of as one in which the thickness was small enough, compared to the other two dimensions, so that a temperature gradient exists only normal to the surfaces of the plate. This assumption will be made to establish one-dimensional heat flow …

Heat Transfer Coefficients In Artificially Roughened Pipes, Mehmet Hayati Turan

Masters Theses

"The purpose of this investigation is to determine experimentally the effects of three different types of artificial roughness on the convective heat transfer coefficient in a pipe and compare these values with that for a smooth pipe for turbulent flow"--Introduction, page 7.

Temperature Distribution In A Semi-Infinite Solid As A Function Of The Input Heat Flux, Lloyd Carl Laciny

Masters Theses

"In this thesis the problem of varying heat flux into a semi-infinite solid initially at zero temperature is investigated. Varying heat flux means that the heat transferred to the solid by its surroundings is a function of time; in this particular problem it is chosen to be an exponential function of time. A semi-infinite solid is one which is bounded by only one plane.

This subject has achieved considerable importance in the field of space technology. A body in space is beyond the realm of aerodynamic heating and non-uniform skin temperatures reached as a result of radiation from a high …

Heat Transfer In A Vortex Flow Metal To Air, Elisha Rachovitsky

Masters Theses

"In this study heat transfer in a vortex flow has been investigated experimentally and analyzed qualitatively.

Air was forced through a Ranque tube in order to get a swirling turbulent flow in its "hot" section. The test section, having a diameter of .355 inches and a length of 27.5 inches, was heated by an induction coil.

Three types of flow were under investigation: a linear turbulent flow, a vortex uniflow and a mixed vortex-linear turbulent flow.

The experiments covered a range of tube-wall temperature from 570 to 900 Deg. R and inlet pressure to the vortex generator ranged from 25 …

A Method Of Fuel Testing In A Cfr Engine, George R. Baumgartner

Masters Theses

"At the present time, only a very small fraction of motor fuels produced for domestic use in the United States contain any alcohol in their blends. Soma foreign markets, notably the Philippine Islands and South American Countries use high proportions of alcohol in their motor fuel blends. Special purpose fuels in the United States which have alcohol blended with other compounds, have been used for engines from which maximum horsepower output is imperative. An example of this type of motor fuel blend might be found in the competitive motor sports involving motorcycles, stock automotive equipment, and special racing equipment.

An …

Stress Distribution In Splined Shafts In Torsion By The Membrane Analogy, Charles L. Edwards

Masters Theses

"The purpose of this investigation is to determine torsional shearing stress distribution in various shapes of shafts. The project will include shafts with circular boundaries. No attempt will be made to show the relation between stress and applied torque"--Preface, page iii.

The Status Of Gas-Lubricated Bearings, Bhaskar Dattatraya Shiwalkar

Masters Theses

"The idea of gas-lubricated bearings was suggested as far back as 1854 by Hirn, but it is only very recently that they have aroused a great amount of interest. The interest is centered on the advantages of gas-bearings for the following major applications:

1. High temperature lubrication where ordinary liquid or grease lubrication fails.
2. Bearings operating in radio-active atmospheres where conventional lubrication may break down.
3. Applications sensitive to contamination where fouling from lubricating oil becomes serious.
4. Low-friction devices--an especially important advantage because of the trend to high speed machinery.
5. Applications where positional accuracies down to micro-inches are required.

As a result …

The Determination Of The Heat Transfer Film Coefficients Of Internally Heated And Twisted Strips, Karpurapu Venkata Apparao

Masters Theses

"As the demand for power supply is increasing, the power from nuclear fission is assuming an important role in the field of power production. The enormous quantity of heat generated during the fission process can be utilized for the generation of power. To get maximum advantage out of the fission process, the fission material must be fabricated into a unit of proper shape to permit the control of the process and safe removal of heat generated. This unit, composed of fuel elements is known as the reactor core and is one of the major concerns in nuclear power development.

The …

The Effect Of Boundry Layer Control By Passing Fluid Through Transverse Slots On Heat Transfer From A Pipe, Perakatte Joseph George

Masters Theses

"The object of this work is an experimental investigation into the possibility of obtaining an increase in the forced convection heat transfer coefficient for a pipe by passing the fluid through narrow transverse slots cut in the pipe, and thereby altering the boundary layer pattern.

Since the greatest barrier to the flow of heat from a solid to liquid exists at the boundary layer, it can be expected that any device which will alter the boundary layer pattern will alter the heat transfer coefficient. When mass crosses a boundary layer in a direction perpendicular to the main motion of the …

Effect Of Boundry Layer Control, Through Surface Holes, On The Film Coefficient Of Convective Heat Transfer, Jainti Prasad

Masters Theses

"This thesis has as its objective, the effect of some boundary layer control on the convective heat transfer film coefficient, metal to liquid. The boundary layer control was produced by drilling 1/16 inch diameter holes on the tube surface.

In this modern world of atoms and the current development of large quantities of its energy at low cost, the subject of designing heat exchange devices of higher efficiency is receiving considerable attention. In a reactor, or any type of heat exchange device, there are limits for the temperatures of a heat exchange surface because of corrosion, strength of metals etc. …

An Experimental Study Of The Effects Of Additives On The Collapsibility Of Carbon Dioxode-Sodium Silicate Bonded Foundry Cores, Robert G. Liptai

Masters Theses

"Every foundry is searching for methods and tools to raise product quality and production while lowering cost. In early 1954 published articles on the new carbon dioxide-sodium silicate process of core hardening began to stir the imagination of most of the foundries throughout the United States, This process has probably claimed more space in the foundry journals than any other subject, hailed by some as a cure-all and dismissed by others as unsatisfactory.

The list of advantages of this process was impressive, but anyone associated with the process was confronted with daily problems that had to be solved regardless of …

Critical Load For A Rectangular Plate Simply Supported On Three Edges, Built In On The Fourth Edge, And Compressed On Two Opposite Simply Supported Edges By A Load In The Plane Of The Plate, Bert Louis Smith

Masters Theses

"There are many engineering structures in which thin plates are used extensively, some examples of which can be found in ship and airplane structures, bridges, etc. The problem contained in this thesis is the analysis of a thin rectangular plate simply supported on three edges, built in on the fourth edge, and compressed on two opposite simply supported edges by a load in the plane or the plate. This problem becomes one of stability, and the object of the solution is to find the smallest load that will cause the plate to buckle"--Introduction, page vi.

Bonded Joint Strength Versus Loading Rate, Charless William Fowlkes

Masters Theses

"The purpose of this investigation was to determine the influence of the rate of loading variable on the apparent shear strengths of joints bonded with some of the currently available metal-to-metal adhesives. The effects of this variable are sometimes neglected by testing laboratories. The results of an experimental evaluation of the mechanical behavior of a group on modern metal-to-metal adhesives as a function of the rate of load application are used to more accurately establish the importance of rate of load considerations in adhesive joint testing. An attempt is made to explain observations of other investigators engaged in adhesive joint …

Steady State Temperature Distribution In A Rotating Disk, George Henry Morgan

Masters Theses

"The purpose of this investigation was to obtain an expression for the steady state temperature distribution of a disk of uniform thickness rotating at a constant speed in ambient air while absorbing heat through the periphery at a constant rate. Engineers encounter such problems in connection with brakes of several varieties. The general solution obtained here could be extended to similar physical problems such as grinding wheels, disk clutches, and so on.

A differential equation was obtained for the temperature in the disk by the application of Fourier's conduction law and Newton’s convection law. A solution of this equation was …

Unsteady State Heat Transfer From A Hot Body To A Liquid, Larry Clinton Atha

Masters Theses

"The problem investigated in this thesis is that of unsteady state heat transfer from a hot body to a liquid, a quenching problem. Unsteady state or transient heat transfer is heat transfer in which the temperature distribution changes with time.

If a hot body was suddenly quenched in a large mass of liquid, a film of vapor would form between the hot body and the liquid. For example, if a hot body was quenched in water a film of steam would form between the hot body and the water. It is the purpose of this thesis to determine the heat …

Stability Of Rectangular Plates By Arbitrary Deflection Method, James Arthur Jones

Masters Theses

"Many engineering structures use thin rectangular plates as members. These plates may be loaded and supported in numerous ways. The edges may be freely supported, rigidly supported, or supported by elastic members. The load may be applied normal to the plane of the plate, in which case the problem becomes essentially one of bending. If the load is applied in the plane of the plate, placing it in compression, the problem becomes one of stability.

This investigation is concerned with the stability of plates rigidly supported on all edges and having a compressive load applied to two opposite edges of …