Mechanical Engineering Commons^™

The Design, Construction, And Calibration Of A Hydrodynamic Journal Bearing Testing Machine., John H. Roberts

Masters Theses

"The purpose of this investigation was to design, construct, and calibrate a journal bearing testing apparatus. The design, construction, and operation of the apparatus are described.

Two bronze bearings with length to diameter ratios of 1.0 and 0.5 were tested using a gravity oil reed system. The speed and the location of inlet oil supply were varied, and the resulting coefficients or friction, oil flow rates, outlet oil temperatures, bearing shell temperatures, and eccentricities of the bearings were determined. These results were evaluated and compared with theoretical solutions.

The results compared favorably with the theoretical solutions and substantiated the use …

An Investigation Of A Constant Velocity Paper Unwinding Device, Jerry L. Gilmore

Masters Theses

"This thesis outlines one approach in designing a system which involves a second order nonlinear differential equation. A large number of variables are involved in this analysis. Therefore, there are many solutions to the problem but only a few of these will satisfy all required conditions. The analysis will be aided by the use of an analog computer. This computer can be manipulated to obtain optimum values for the different variables.

The computer results are presented in graphical form. Reasonable values for the different variables are obtained from these graphs.

The characteristics of the unwinding device were simulated on the …

Convective Heat Transfer In Small Enclosed Air Spaces., Joseph Charles Kroutil

Masters Theses

No abstract provided.

Parameters In Ablation Heat Sheilds, Franklin Chang Liang Lin

Masters Theses

"The desired result of this paper is a method of determining temperature distribution and burn off rate in a semi-infinite rod or shield subjected to a large heat flux. The possible methods of determination were investigated, and it was felt that an analytical approach turned out to be the most feasible.

The analytical analysis employed involves the use of the Fourier's general equation for one dimensional heat flow. Transformations from stationary to moving coordinates reduces the problem from unsteady state to steady state boundary conditions. The resulting equations can be applicable to the extent for the heat flow problems involving …

Thermocouple Shape Influence On Response In A Dynamic Compressible Fluid Atmosphere, Philip J. Steger

Masters Theses

"This investigation was performed to determine whether the geometrical shape of a thermocouple used to measure the temperature of a dynamic fluid atmosphere had any affect on its recovery factor and time response.

A converging nozzle was used to establish a dynamic fluid stream in which shaped silver solder junctions of copper-constantan thermocouples were tested. The velocity of the working fluid, air, was about 1000 ft/sec at the test point.

The investigation was successful, within experimental limits, in determining that the recovery factor of a bare thermocouple junction is not influenced by geometrical shape The results agreed substantially with available …

The Design, Construction, And Calibration Of An Apparatus To Determine The Thermal Conductivity Of Solids, Alan Edward Stephenson

Masters Theses

"Many pieces of equipment have been designed to determine the thermal conductivity of solids. They all, however, depend on the application of Fourier's equation of heat conduction in solids to determine the thermal conductivity. The apparatus used in this investigation is a modification of the guarded hot plate method used by the American Society for Testing Materials. Operation of the device is given in a step by step procedure both as a guide for others and also to show how it was operated during calibration of the apparatus. Data obtained in the calibration is given in tabular and graphical form …

A Study Of Rotational Critical Speed For A Multi-Mass System, Richard K. Brockmann

Masters Theses

"The object of this thesis is to demonstrate, by use of an IBM-1620 digital computer, a fast efficient method for locating natural frequencies of multi-mass rotational systems. Stress and deflection characteristics are examined at these frequencies also.

The shafts considered in this thesis are simply supported and symmetrically loaded with five concentrated masses. These five masses are placed at increments of 10 inches on a 60 inch shaft. The variable to be examined is shaft diameter, which is varied from 0.2 inch to 1 inch by increments of 0.2 inch. The effect of shaft weight, which is a function of …

Experimental Stress Analysis Of Bolts In A Flange Coupling, Bansidhar Shah

Masters Theses

"This thesis deals with the strength of a bolted joint which is subjected to tensile and bending loads. The purpose of this investigation was to derive expressions for the stresses developed in the bolts and the load producing separation of the joint.

A laboratory study of a flange coupling was made and the behaviour of flange bolts under different clamping forces was studied in tension and bending tests. The strain in the bolt was measured by mounting the strain gages on the shank of the bolt. From this, a graph of applied load versus strain in the bolt was plotted. …

A Survey Of The Methods Of Gas Analysis, Yadvendra V. Desai

Masters Theses

"The object of this thesis is to survey the different types of gas analyses. Subject concentration will be centered on the general and specific instrumental methods of gas analysis. A general account of continuous automatic gas analyzers will be included. References are included for the use of those who desire a more comprehensive knowledge of a specific method of gas analysis.

During recent years, the importance of gas analysis has been considerably increased with the advancement of science and technology. Gas analysis mainly involves the identification, quantitative evaluation and separation of the components of a gaseous mixture. Thus it includes …

Thermal Conductometer For Liquids, Yuan-Kai Chang

Masters Theses

"The published data pertaining to the thermal conductivity of liquids are of such a character that it is very difficult to determine from them the correct value, or the temperature coefficient for any liquid.

Most of the published values of thermal conductivity for liquids are evaluated at one particular temperature. It is the purpose of this investigation to design, construct and calibrate a thermal conductometer for liquids over a temperature range of 30°F to 200°F.

Since water and glycerol were the only liquids found by this investigator with published data on their conductivities as a function of temperature, they were …

Experimental Evaluation Of Thermal Strains And Stresses, T. F. Lehnhoff

Masters Theses

"This investigation is the study of a method for the experimental measurement of thermal strains. Using four electric strain gages (two of one type and two of another) the method will yield the normal and shear strains as well as the temperature change in any biaxial stress field. The gage types must be chosen for the range of temperature in which it is desired to measure the thermal stresses. The method described eliminates the need for extra resistors, thermocouples, unrestrained dummy gages at the same temperature as the active gages, special alloy gages for each type of metal and special …

Transpiration Cooling Of A Heat Generating Porous Plate, M. K. A. Hameed

Masters Theses

"This investigation is a continuation of a thesis by T. S. Purewal. Several of the simplifying assumptions made by the above author are either ignored or the justifiability of such assumptions is probed into in order to obtain a more rigorous solution. Effects of the assorted grain size, non-Newtonian cooling, direction of coolant flow, thickness of the porous heat generating plate, specific heat of the coolant, and compressibility of the coolant are investigated in this thesis. Variation of maximum temperature of both coolant and the solid material for different types of heat source distribution are also studied.

As the grain …

Analog Study Of Vibratory Forces In Sorting Machine, Navnit Chhaganlal Mehta

Masters Theses

"This investigation involves the study of the reduction of vibratory forces in a sorting machine. The equivalent masselastic system is shown in Figure 1, in solid lines. In this figure the mass m₁ represents the main structure for the mounting of the machine, the mass m₂ is the main bearing blocks and the mass m₃ is the vibrating basket. The elastic stiffness indicated as k₁ represents the mounting spring for the entire unit, the stiffness k₂ is that of the beam structure by which the bearing block is attached to the main structure, and the stiffness k₃ is that of …

A Study Of The Problems Of Design Of Optimum Vibration Absorbers For Multi-Mass Systems, James C. Villegas

Masters Theses

"The purpose of this investigation was to continue the preliminary work of Burrows on the application of tuned and damped vibration absorbers to the reduction of vibratory stresses in a multi-mass torsional vibration system. A hypothetical engine system was chosen for both investigations because it had many complicating factors and gave an eminently practical subject for study.

Attention was centered on the reduction of stresses resulting at higher speeds of the machine system and on developing methods and criteria for the designing of effective absorbers where several modes of vibration exist in the operating speed range of the machine"--Abstract, page …

Refrigeration Heat Transfer Characteristics Of An Artificially Cooled Trout Pond, Richard G. Murray

Masters Theses

"In many locations natural summer lake and pond temperatures are too great for the practical production of trout for fishing purposes.

The purpose of this thesis is to investigate the refrigeration capacity required to maintain a pond of water at a temperature that provides a healthful environment for trout.

The over-all refrigeration load for this application was sub-divided into four categories; conduction, convection, evaporation and radiation. Each type was solved by analytical means using suitable boundary conditions and simplifications. It was necessary to determine one boundary condition for the conduction heat transfer by an empirical method.

The results of this …

A Study Of Heat Transfer Coefficients On Cylindrical Pipe In Turbulent Flow, Dennie Lee Adkins

Masters Theses

"This thesis represents a study of the effects of turbulent motion on heat transfer coefficients on cylindrical pipe.

The turbulent motion was created by cutting transverse slots in a spiral configuration along the pipe length.

An induction heater was used for the heat source and water as the cooling medium. The water was conducted over the pipe surface and through the slots.

This caused the laminar layer along the pipe surface to be broken up and an increase in the heat transfer coefficient was experienced.

The main objective of this test was to find if a relation existed between the …

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 …