Engineering Commons^™

Investigation Of Free Convection Heat Transfer From An Inclined Flat Plate, Phairojna Sang-Urai

Masters Theses

"The experimental investigation was conducted to determine temperature distribution and convective heat transfer coefficients in terms of Nusselt number for an inclined heated flat plate in air. The heated surface of the aluminum flat plate was set facing upward and moved through seven positions from the vertical to the horizontal. The investigation shows that the local Nusselt number can be predicted by Kiekus's solution within 12 per cent for inclination angles from the vertical through 75° from the vertical. In the case of the vertical position, Eckert's solution gives a better prediction. For the horizontal position the results show good …

A Fluidic Liquid Level Control System, Vinod Kumar Verma

Masters Theses

"The prime objective of this investigation was to design and construct a working "Fluidic liquid level control system", and to make a functional study of the characteristics of the devices employed therein. A working model of a "fluidic liquid level control system" is developed and experimental data is collected to describe the functional characteristics of the fluidic circuits employed. The system contains a pressure sensitive, variable frequency oscillator; appropriate demodulation stages to convert the variable frequency alternating signal into a varying non-alternating signal; and on-off control elements in the final stages"--Abstract, page ii.

Coupled Transport Of Heat And Mass In Laminar Tube Flow, Lung-Mau Huang

Masters Theses

"The object of this investigation is to study the mutual dependence of heat and mass transport in laminar and hydrodynamically developed tube flow. Consideration is given to gas flow through a tube whose wall is coated with a sublimable materials so that heat and mass transfers take place between the wall and the flowing gas stream. The tube wall is thermally insulated from the external environment, with the result that the latent heat required by the sublimation process at the wall is supplied solely by convective transfer from the gas. The analysis of the problem requires simultaneous solution of the …

Film Boiling Of Nitrogen From A Spherical Heating Surface At Atmospheric Pressure And Standard Gravity, Juan Jorge MariáNyi

Masters Theses

"A steady state film boiling heat transfer study was conducted at atmospheric pressure, with a heated sphere as the heat transfer surface and liquid nitrogen as the boiling medium. Results indicate that the heat transfer rate in film boiling is not the same around the sphere. For the same heat flux, heat transfer at the sides of the sphere takes place at higher temperatures than at the bottom of the sphere. The data were compared with the equation of Frederking and Clark for spheres (1̲8̲), which was derived to predict steady state conditions at standard, fractional and near zero gravity. …

An Unsteady-State Method For Determining The Thermal Conductivity Of Materials, Richard H. Bulmer

Masters Theses

"Originally this work was initiated to develope [sic] a method for measuring the thermal diffusivity and thermal conductivity of metals. Due to the characteristics of the method and the equipment used, it was concluded that the technique is not suitable for materials of high conductivity. However, results show that the apparatus is valuable for the determination of the thermal diffusivity of relatively poor heat conductors. The favorable characteristics of the method are its rapidity and basic simplicity"--Abstract, page ii.

Evaluation Of Methods For Analysis Of Multi-Degree-Of-Freedom Systems With Damping, Brijgopal R. Mohta

Masters Theses

"A general review of various methods for studying the behavior of linear lumped parameter systems with viscous damping is presented. Five methods are discussed. These are: (1) Normal Mode Technique (2) Ho's Method (3) Impedance Method (4) Graphical Technique (5) A Method for Reducing Degrees-of-freedom. For solution of vibration problems by the Normal Mode Technique, the systems are classified as (1) classically damped or (2) non-classically damped. It is shown that the classically damped systems are relatively easy to solve. For non-classically damped systems, the method proposed by K. A. Foss has been employed. This method is quite complex, but …

Numerical Integration Of Shell Equations Using The Field Method, Pravin R. Ghael

Masters Theses

"In this work field equations are introduced to numerically solve the six linear differential equations which determine the displacements and stress resultants for thin elastic shells with axially symmetric loadings. With the applications of the field equations to the analysis of symmetric shells, the two-point boundary-value problem is formulated in terms of twelve first-order ordinary differential equations with boundary conditions at only one point. These equations are solved by using a forth [sic]-order Runge_kutta integration formula. Three problems whose solutions are known have been evaluated to check the accuracy of the field equation method. These are: (1.) Simply-supported, thin circular …

Constant Horizontal Force Machining Through Flash Welded Steel Bars Of Varying Hardness, Donald Naeger

Masters Theses

"The purpose of this experiment was to determine the effect of a constant horizontal force applied to the carriage of a lathe as it turned a piece of stock which consisted of two steel bars, of different hardness, flash welded together. This experiment was performed on a lathe to which a pulley system with a mechanical advantage of six was attached to the carriage. The strain on the tool was measured both in the horizontal and vertical directions by a tool dynamometer on which eight strain gages were mounted. The strain gages were calibrated on a Tinius-Olsen testing machine. The …

Analytical And Experimental Methods For Determining The Properties Of Materials At Very High Rates Of Loading, A. G. Behring

Masters Theses

"In the following report, some of the properties of ALCOA 7075 T651 aluminum, when subjected to high rates of loading, are experimentally investigated by impacting two rods of the material longitudinally. One rod is accelerated to a uniform velocity with an air gun launcher. The stationary second rod is instrumented with strain gages on its lateral surface in order to determine the strain-time history following impact. A detailed description of the experimental equipment is included. Simple, one-dimensional theory is used to determine the dynamic, elastic modulus of the test material under the impact condition. Several observations regarding the behavior of …

Drag Reduction In Hydrocarbon Soap Solutions, Ian Radin

Masters Theses

"Turbulent flow pressure drop measurements were made for solutions of aluminum dioleate (soap) in toluene at concentrations of 0.2, 0.5, 0.75 and 1.0 per cent. Tube diameters ranged in size from 0.01 to 2.0 inches. The results of these measurements differed from those observed in aqueous systems. Higher concentrations (at least 0.75 per cent) were required before drag reduction was observed. Although fresh solutions were somewhat sensitive to shearing, once a solution was over about two weeks old it showed little further mechanical degradation. Although in the toluene solutions, wall shear stresses were reached which were over an order of …

Instrumentation Of A Shock Tube Facility, James Everett West

Masters Theses

"The theory of schlieren and interferometer systems was described and related to studies of shock waves in a shock tube. An interferometer was procured and a schlieren system was modified for use with the UMR shock tube facility. The design and construction of a base for the systems and window assemblies for the shock tube comprised the major portion of the work on this project. A short series of tests were run to ascertain the compatibility of the instrumentation to the UMR shock tube facility. While no schlieren photograph of the shock wave was obtained, the system was shown to …

Investigation Of Thermal Resistance At The Interface Of Dissimilar And Similar Metals, Ching-Liang Lin

Masters Theses

"Experiments have been conducted to investigate the resistance and the effect of the directional heat flow at the interface of metals in contact. The test specimens were cylinders, axially aligned and dead weight loaded. Specimen materials were aluminum, bronze, and steel. The tests were conducted at environment pressures of 5x10⁻⁵ Torr. or less. The dead weight load was kept at 10 lbs. for all tests and the surface roughness for all specimens was from 6 to 8x10⁻⁶ inch. The results of the investigation reveal that the resistance to heat flow at the interface of metals decreases as the interface temperature …

An Experimental Method Of Determining The Thermal Accommodation Coefficients Of Metallic Surfaces, Raymond John Dethorne

Masters Theses

"In the free molecule regime, Knudsen number greater than 10, heat is transferred from a solid by radiation and conduction. The ability of a surface to emit radiant energy is governed by a surface property called emittance while the surface property which apparently regulates the amount of heat transferred by conduction is called the thermal accommodation coefficient. This thesis presents the results of an experimental investigation to determine a relationship between these two properties, emittance and thermal accommodation coefficient. A test apparatus was constructed to measure both the radiation and conduction contributions between two concentric cylinders. cylinders of aluminum and …

A Study Of Swirling Air Flow In A Converging Nozzle, Charles William Lineberry

Masters Theses

"A study was conducted to determine the behavior of swirling air flow in a converging nozzle. Special instrumentation was constructed to obtain radial traverses of the flow at four axial positions. the data collected consisted of velocity, static pressure, and stagnation temperature. The flow pattern demonstrated the Ranque-Hilsh effect and reversed axial flow in the core region. As the flow entered the nozzle, it had the characteristics of a free vortex. At the exit plane the characteristics were those of a forced vortex. The converging nozzle caused an increase in the magnitude of the axial velocity component"--Abstract, page ii.

Optimum Fin Spacing For Heat Transfer Per Unit Length Of Heat Exchange Section, Glenn Ellis Miller

Masters Theses

"This thesis presents the results of an experimental study of the heat-transfer ability of a finned surface as a function of the spacing between fins. The results are expressed as heat transfer per unit length of finned section rather than the heat transfer per fin. Circumferential steel fins, seven and three-quarter inches in diameter, were used for the investigation. Data was taken for fin spacings ranging from zero to one and one-half inches. The experimental heat-transfer rate to atmospheric air was determined by measuring the volume of saturated steam which condensed in the test section over a measured time interval. …

Convective Heat Transfer In Small Cylindrical Enclosures Heated From Below, Donald Wayne Land

Masters Theses

"Free convection in enclosed air spaces is often of prime importance in the design and analysis of panels utilizing the insulating properties of air and other gases. Previous investigations were performed on very thin air layers.

This thesis presents the results of an experimental investigation to determine the heat transfer by convection and conduction through air layers with relative sizes in terms of length/diameter ratios of one-fourth to one.

Eight cylindrical samples were tested. Four had inside diameters of 2.0 inches, and the others were 2.75 inches in diameter. Heat was transferred across the air layers by both conduction and …

Film Boiling From Horizontal Plates With Low Thermal Capacity, K. M. Ragsdell

Masters Theses

"The object of this investigation was to obtain data for saturated film pool boiling from a low thermal capacity flat plate at atmospheric pressure. A test plate, constructed from resistance strip, was placed horizontally in a pool of liquid, and was heated electrically. Refrigerant-11 and nitrogen were used as the boiling liquids. Heat transfer results were obtained in both fluids over a temperature range of approximately 1200F⁰ (400-1600⁰F). Surface size, roughness and orientation effects were observed for flat horizontal heated surfaces with one dimension near the most dangerous wavelength. No surface material effect was observed. Excellent correlation of the data …

A Study Of Film Boiling Of Liquid Nitrogen And Liquid Argon Over A Wide Pressure Range With Cylindrical Heaters, V. J. Flanigan

Masters Theses

""A film boiling heat transfer study was conducted with three different diameter cylindrical copper heaters over a wide range of pressures for nitrogen and argon with the heat transfer surface in the horizontal position. The data were compared to the commonly used film boiling heat transfer relations. The common relations were found to be considerably in error for the range of variables covered in this investigation. A semi-empirical equation for corresponding states fluids which correlates the available data as a function of the reduced temperature and reduced pressure was derived and discussed"--Abstract, page iii.

The Transient Dynamics Of Plane Mechanisms, Navnit Chhaganlal Mehta

Doctoral Dissertations

"Accurate determination of dynamic characteristics of mechanisms has become more important with increased requirements on speed, efficiency and precision. Many devices, such as circuit breakers and computing mechanisms, operate under purely transient conditions and actuation time places a serious limitation on the response of the system of which these devices are a part.

In the classical analysis, whether it be graphical or analytical, the mechanism is assigned a specified position and state of motion from which the forces required to produce the motion can be determined. The inverse problem of specifying the driving force and determining the resulting motion, which …

The Design And Construction Of An Apparatus For The Plane Wave Analysis Of Mufflers, Stephen Philip Buckley

Masters Theses

"In the following report, a method for evaluating the attenuation characteristics of a general muffler as well as the design, construction and use of the associated apparatus are described. The method combines accepted plane wave theory and experimental techniques into a relatively straightforward approach to the analysis of acoustic filters. Equations are developed to cover the frequency range between 300 and 4000 cycles per second. Deviations from these equations extend the use of the equipment to low frequencies without the need for unduly long and cumbersome apparatus. This method, which may be called the standing wave method, utilizes a standing …

An Investigation Of The Effects Of An Impact On Some Of The Mechanical Properties Of Aluminum Alloy 2014-T6, Rajnikant K. Shah

Masters Theses

"Static and impact tests were conducted on an Aluminum alloy 2014-T6 specimen. The purpose of this research was to determine the effects of an impact load on some of the mechanical properties of aluminum. The cross section of the specimen measured 4.438 in. by 3.850 in. and it was 12 in. long. It was equipped with a total of four electric resistance gages connected in two pairs. One pair measured longitudinal strain while the other measured transverse strain. Both gages in each pair were mounted on the opposite sides to cancel the bending effect. In the static tests, load was …

Measurement Of The Velocity And Temperature Profiles Of Air Swirling Through A Conical Shaped Nozzle, Stephen Abner Thompson

Masters Theses

"A study was conducted to determine the velocity and temperature distributions in swirling flow of air through a converging nozzle. Radial traverses were taken at three axial positions with a specially designed pitot tube constructed of hypodermic needles. The most significant finding was the large magnitude of the radial velocity component. A combination of reversed axial flow along the nozzle axis, and an outward flow near the nozzle surface was also experienced. An increase of temperature with increasing radial position may be attributed to the Ranque-Hilsch effect"--Abstract, page ii.

Empirical Evaluation Of The Eccentric Orifice In Small Diameter Pipes, Gary A. Hinz

Masters Theses

"This investigation has taken different orifice sizes (0.3005", 0.4000", 0.5045", 0.6015") and tested their flow characteristics when used in a 1" diameter pipe. Each orifice was initially placed in a fully eccentric position, that is the circumference of the orifice was placed tangent to the inside circumference of the pipe. Data was taken with the orifice eccentric to concentric in increments of 0.050".

Plots of flow coefficient versus Reynold's number were made for each position of the four orifices tested.

Empirical equations were developed for determining the flow coefficient of the various orifice sizes placed in any eccentric position.

It …

A Fluid Control System For Nuclear Reactors, Roger Alan Crane

Masters Theses

"This thesis presents both an experimental and analytical analysis of the scram characteristics of a fluid control system for a nuclear reactor. This control system utilizes a control tube containing a neutron-absorbing fluid. The level of the fluid inside of the tube is then regulated by means of' a pressurized gas and offers a number of unique advantages over the conventional control rod system using linear absorber rods.

The effect of varying the level-control pressure and initial height of the fluid column is determined and evaluated. The time required to complete a scram with the fluid control system is compared …

A Study Of Modified Plug Designs For A Globe Valve, Robert W. Wagner

Masters Theses

"This thesis presents an empirical study of the characteristics of a cylindrical skirted disk valve used as a flow regulating device. Holes were drilled in two separate removable cylinders, which, when respectively attached to the valve plug adapter, provided control of the flow rate. These cylinders could be moved to permit exposure of more or less flow area by means of the valve stem and crank mechanism. At the closed position of the valve no holes were available for flow within the differential pressure zone of the valve, while at the full-open position all the drilled holes were within the …

A Study Of The Effect Of A Square Cutout On The Moment Distribution In A Simply Supported Rectangular Plate Under Normal Concentrated Load By The Moiré Fringe Method, Taher F. Raja

Masters Theses

"Plexiglass models were used to produce Moiré fringes for two different geometrical shapes. The moments in the case of a simply supported rectangular plate with a normal concentrated load were found using the Moiré fringes which directly give the gradients at all points of the surface of the model. The variation of the moments due to a square cutout was also studied by this method. As a check for the experimental method, the analytical solution was presented for the plate without a cut-out. The Moiré method yields moments to an accuracy of 3 to 15 percent, however, care must be …

Approximate Solution Of The Momentum And Energy Equations For Partially Ionized Argon, Sir-Hoi Chen

Masters Theses

"Based on available experimental data, the transport properties of partially ionized argon gas have been determined by solving the integral equations of momentum and energy conservation by an approximate method. The momentum and the energy conservation integral equations are solved simultaneously by an iteration method by assuming both parabolic and cubic velocity and temperature profiles separately. The results are compared with the case of linear velocity and temperature profiles"--Abstract, page iii.

Calibration Of An Instrument To Calibrate Accelerometers, Nader Khorzad

Masters Theses

"The purpose of this research was to calibrate an instrument with which an accelerometer could be calibrated accurately. The instruments used were a piezoelectric shaker and a modified Michelson interferometer together with necessary electronic equipment. This equipment was used to calibrate a Kistler Model 808A accelerometer.

Weight was added to the shaker in the second part of this experiment in order to determine its effect on the amplitude and frequency of oscillation of the shaker.

Results show that this instrument may be used to calibrate an accelerometer quite accurately. The weight added to the shaker will effect only the amplitude …

Effect Of Artificial Roughness On Convection, Lee W. Burford

Masters Theses

"Considerable work has been done in recent years, and is still being done, to find ways of increasing the heat transfer rate in fluid heat exchangers. One particular type of potential heat exchanger that has been studied analytically, as well as experimentally, is the use of artificially roughened tubing.

The test sections used in this experiment consisted of four aluminum pipes, three of which have been artificially roughened internally by machining ninety- degree V-shape grooves along the axis of the pipes. The grooves were 30/1000, 60/1000, and 90/1000 inches in depth. The remaining pipe was a smooth test section with …

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 …