Engineering Commons^™

An Examination Of Railroad Capacity And Its Implications For Rail-Highway Intermodal Transportation, David Bruce Clarke

Doctoral Dissertations

After many years of decline in market share, railroads are now experiencing an increasing demand for their services. Service intensive intermodal transportation seems to be an especially promising market area. Since the historic decline in traffic has been accompanied by a reduction in network infrastructure, however, the railroads' ability to handle sizable traffic increases, at least in the short term, is in question. Since rail transportation is critical to the domestic economy of the nation, and is increasingly important in international logistics channels, shortfalls in railroad capacity are not desirable.

The published literature on railroad capacity is relatively sparse, especially …

Application Of Pulse Calorimetry To Metal Systems, Debasis Basak

Doctoral Dissertations

The pulse calorimeter developed as a part of the author's masters thesis was used extensively in the doctoral research to determine the electrical resistivity and specific heat of Ni, Ni₄Mo, Fe-A1 alloys and Ni-A1. The temperature range of measurements varied with different specimens but in general were between 375 K to 1300 K.

The pulse calorimeter essentially consists of a specimen in series with a standard resistor and a programmable power supply. The specimen is inside a vacuum chamber. The programmable power supply can be triggered from the computer to send a specific current to the specimen for …

Monitoring And Prognosis Of Plant Components, Jeffrey Banks

Masters Theses

Many predictive maintenance approaches focus primarily on fault monitoring and diagnosis of rotating machinery. Today's industrial "reliability-based" maintenance programs implement vibrational analysis techniques as a sound foundation in minimizing unnecessary machine downtime. These approaches, based upon on-line data acquisitions and analysis may be used to increase component availability and ultimately forecast remaining life. Depending upon the specific type of machinery under consideration, measurements such as temperature, voltage, current, rotational speed, power, and torque may be analyzed to enhance machinery diagnostics capability.

The purpose of the proposed research is to formulate and implement a methodology to estimate the remaining useful life …

Atec: The Aerodyanmic Turbine Engine Code For The Analysis Of Transient And Dynamic Gas Turbine Engine System Operations, Glenn Douglas Garrard

Doctoral Dissertations

A new one-dimensional, time dependent aerothermodynamic mathematical model and computer simulation of the gas turbine engine has been developed and is introduced herein. The Aerodynamic Turbine Engine Code (ATEC) simulates the operation of the gas turbine engine by solving conservation equations, expressed as one dimensional, time dependent Euler equations, with turbomachinery source terms. By incorporating both implicit and explicit equation solvers, transient simulations of the gas turbine engine can be conducted efficiently while maintaining the capability of simulating dynamic events such as compressor stall. ATEC can also be used to address dynamic events or steady-state processes to model both on- …

Elastic-Plastic Fracture Toughness Determination Under Some Difficult Conditions, Kang Lee

Doctoral Dissertations

The J_Ic value and J-R curve have been widely used to characterize elastic-plastic fracture behavior in modern engineering practice. Their determination has been standardized. To Determine the J_Ic value and the J-R curve using the ASTM standard test methods, three measurements, load, displacement and crack length, must be obtained simultaneously from the test. This may sometimes be difficult or even impossible due to the restrictions of test equipment, adverse environments, test conditions or test arrangements.

Recently, a method of normalization has been introduced by Landes and his group as a convenient way for J-R curve determination. This method …