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Title: Installation and test of an International Harvester co. gasoline engine
Creator: Peck, Winfield, Llewellyn, Kenneth
Date: 2009, 1911
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/installationtest00peck
Thesis (B.S.)--Armour Institute of Technology, 1911 B.S. in Mechanical Engineering, 1911

Title: DESIGN OF MODERN HIGH NB-CONTENT ,-,' NI-BASE SUPERALLOYS
Creator: Antonov, Stoichko
Date: 2017, 2017-07
Description: Superalloy design can prove to be a very complex and challenging task, as certain elemental additions can significantly improve properties...
Show moreSuperalloy design can prove to be a very complex and challenging task, as certain elemental additions can significantly improve properties when added in high contents, however, exceeding their solubility limits can promote the formation of undesired phases at grain boundaries as well as grain interiors, and can quickly deteriorate the high temperature structural integrity and stability of the alloy, resulting in a catastrophic failure. Precipitate phases, such as " and ⌘, appear similar and are often mistaken for one another, leading to the need for a better fundamental understanding of their formation, required for developing innovative new classes of Ni-base superalloys. The morphology, formation, and composition of precipitate phases in a number of experimental alloys spanning a broad range of compositions were explored and compositional relationships were developed to facilitate the design of !-!0-("/⌘) Ni-base superalloys. The e↵ect of increasing Nb alloying additions on the formation and long term phase stability of topologically close packed (TCP) phases was studied. Elevated levels of Nb can result in increased matrix supersaturation and promote the precipitation of ⌘-Ni6AlNb along the grain boundaries in powder processed, polycrystalline Ni-base superalloys, while reduced Nb levels favored the precipitation of blocky Cr and Mo rich $ phase precipitates along the grain boundary. Evaluation of the thermodynamic stability of these two phases using Thermo-Calc showed that while $ phase predictions are fairly accurate, predictions of the ⌘ phase are limited. In addition, atom probe tomography (APT) was used to quantitatively assess grain boundary phase compositions and local segregation along the grain boundary before and after a 1000 hour thermal exposure at 800 "C. The complex network of $ phase precipitates that formed upon the thermal exposure and the characteristic interfacial segregation profiles were studied. In addition, elemental boron was observed to segregate to the grain boundary and phase interfaces, but did not form borides, due to the relatively low concentration of B atoms, resulting from a higher B concentration in the matrix. APT studies were also performed on MC carbides of the alloys and the formation kinetics and morphological differences between NbC and Hf doped NbC were explained using density functional theory (DFT) calculations of the formation energies of different facets of the MC carbide. Detailed electron microscopy and APT techniques were then used to systematically quantify the chemical and morphological instabilities that occur during aging of polycrystalline !-!0 Ni-base superalloys containing elevated levels of refractory alloying additions. The morphological changes and splitting phenomenon associated with the secondary !0 precipitates were related to the discrete chemical compositions of the secondary and tertiary !0 along with the phase compositions of the ! matrix and the ! precipitates that form within the secondary !0 particles. Compositional phase inhomogeneities led to the precipitation of finely dispersed tertiary !0 particles within the ! matrix and secondary ! particles within the secondary !0 precipitates, which, along with surface grooving of the secondary !0 particles, contributed to the inverse coarsening or splitting of the precipitates during aging. As recent studies have shown that polycrystalline Ni-base superalloys containing elevated levels of Nb additions exhibit superior properties at elevated temperatures when compared to existing commercial Ni-base superalloys, understanding of elemental partitioning to each phase is essential and was studied via APT. Compositions of the constituent phases were measured in four high Nb-content !-!0 Ni-base superalloys and the results were compared to thermodynamic database models from Thermo-Calc. Results were also used to predict the solid solution strength behavior of the four alloys. The di↵erences in phase composition predictions from thermodynamic models resulted in dissimilarities between the generated strength behavior curves and those from the experimental work. Finally, creep behavior of high Nb-content !-!0 Ni-Based superalloys was related to the formation of secondary phases mainly at grain boundaries. As secondary phases form, their brittle nature leads to crack formation, which can propagate under the tensile load and lead to premature failure of the alloy.
Ph.D. in Materials Science and Engineering, July 2017
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Title: Analysis of Murgue's Theory for Centrifugal Blowers and Pumps
Creator: Spitzglass, Jacob M.
Date: 2009, 1913
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/analysisofmurgue00spit
Thesis (B.S.)--Armour Institute of Technology

Title: SHIP STATE AND COVARIANCE PROPAGATION USING TIME SERIES ANALYSIS AND FORECASTING
Creator: Katre, Aniruddha
Date: 2014, 2014-05
Description: The Navy's Unmanned Combat Aerial System (N-UCAS) program is currently developing technology for autonomous shipboard landing of unmanned...
Show moreThe Navy's Unmanned Combat Aerial System (N-UCAS) program is currently developing technology for autonomous shipboard landing of unmanned aerial vehicles (UAVs). A high accuracy and high integrity relative navigation algorithm using carrier phase di erential GPS measurements and high rate inertial sensor data has been implemented to land the UAV. Such an algorithm requires ship state information to be broadcast to the aircraft via a VHF data link. The data link is susceptible to failure for reasons such as interference from jamming. This thesis considers the problem of precise ship state propagation on board an aircraft during a data link outage occuring when it is too late for the aircraft to abort its landing approach. Accurately quantifying the estimate error covariance is important for a high integrity and accuracy navigation algorithm. Therefore this thesis focuses on algorithms that can propagate the ship state as well as determine the propagation error covariance. Initially, a simple state propagation using kinematic equations for linear motion is tested. Seakeeping and Maneuvering theories used to model the dynamics of a sea vessel are also considered. However, analysis shows that due to constraints imposed by a data link outage and complexity in accurately modeling some parameters in the ship dynamic model, these two approaches are infeasible. As an alternative to kinematic and dynamic modeling, Time Series Analysis and Forecasting methods for ship state propagation are investigated. This work introduces parametric modeling and forecasting of a time series using linear stochastic models. Maximum likelihood estimate (MLE) and outer product of gradients (OPG) algorithms are implemented for faithful parameterization of time series using ARIMA models. Expressions for forecasting and forecast error variance quanti cation are also developed. These algorithms are then tested using ship data provided by the N-UCAS program.
M.S. in Mechanical and Aerospace Engineering, May 2014
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Title: A COUPLED LAGRANGIAN-EULERIAN MULTIPHASE MODEL FOR SIMULATION OF WIND TURBINES PERFORMANCE UNDER RAINY CONDITIONS
Creator: Cohan, Aiden C.
Date: 2016, 2016-05
Description: Wind Turbines power output is constantly influenced by their environmental conditions, including raining and icing. Therefore, understanding...
Show moreWind Turbines power output is constantly influenced by their environmental conditions, including raining and icing. Therefore, understanding the effect of rain is necessary to enhance the efficiency of the wind turbines used in regions with considerable number of rainy days and below freezing temperatures. We developed a multiphase computational fluid dynamics (CFD) model to estimate the effect of rain by simulating the actual physical process of rain droplets forming a water layer over the blades by coupling the conventional Lagrangian Discrete Phase Model (DPM) and the Eulerian Volume of Fluid (VOF) models. We first applied our model to the National Renewable Energy Laboratories (NREL) S809 airfoil used in the blade profile of horizontal-axis wind turbines (HAWT) and studied the effect of rain at different rainfall rates in addition to the effect of surface tension and surface property of the airfoil. Our simulations showed that surface tension has a dominant effect on the performance of the airfoil and should not be neglected under simulated rainy conditions. It also was observed that, under rainy conditions, an airfoil with non-wetting surface has an inferior performance (lower lift and higher drag coefficient) compared to an airfoil with wetting surface due to the added roughness caused by water on the non-wetting surface, which is in line with experimental observations. We also observed that, at low rainfall rates, the performance of the airfoil is highly sensitive to the rainfall rate. However, if the rainfall rate is high enough to immerse most of the airfoil surface under water, a further increase in the rainfall rate does not have a substantial effect on the performance of the airfoil. We also investigated the effect of rain at different angles of attack for two rainfall rates. We started by running single phase cases and observed that our results agreed well with experimental data. We then ran multiphase cases and observed that, lift coefficient increases with angle of attack even past the stall angle compared to the single phase case. However, this favorable increase in lift is accompanied by an increase in the drag coefficient which is greater at larger angles of attack. Finally, we simulated the performance of an actual 3D wind turbine (NREL phase VI horizontal axis wind turbine) for single phase cases at various wind speeds, in addition to, a multiphase case (under rainy conditions) using our multiphase model. Our single phase results compared well with experimental data. We had to use a simplified version of our multiphase model for the multiphase 3D simulation in order to make it computationally affordable. We observed that rain can reduced the performance of the NREL phase VI wind turbine by about 5% at a wind speed of 7.02 m/s and a rainfall rate of 40 mm/hr. Even though we used our multiphase model to simulate water layer formation from rain droplets, the physical concepts used in developing the model are very general and are not limited to this specific problem. Our model can be used to simulate any problem that involves particles hitting a surface and forming a liquid phase. For example, it can be used to model spray painting of a surface as the spray droplets form a paint layer on the surface.
Ph.D. in Mechanical, Materials and Aerospace Engineering, May 2016
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Title: Closed nozzle tests of a forty gallon chemical extinguisher
Creator: Corman, A., Cowles, R. D., Owen, W. R., Tronvig, W. P.
Date: 2009, 1917
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/closednozzletest00corm
Thesis (B.S.)--Armour Institute of Technology

Title: The coefficient of friction of ball bearings and horse power to drive
Creator: Rehfeldt, H. F.
Date: 2009, 1919
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/coefficientoffri00rehf
Thesis (B.S.)--Armour Institute of Technology

Title: A commericial test of 350 hp Stirling boiler
Creator: Furry, William S, Matchett, James C.
Date: 2009, 1907
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/commericialtesto00furr
Thesis (B.S.)--Armour Institute of Technology

Title: Coke breeze briquetting
Creator: Belke, W. E.
Date: 2009, 1918
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/cokebreezebrique00belk
Thesis (B.S.)--Armour Institute of Technology; Biblography: leaf 83

Title: Comparative test of centrifugal pressure blowers
Creator: Conlin, W. F., Holmes, W. E.
Date: 2009, 1909
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/comparativetesto00conl
Thesis (B.S.)--Armour Institute of Technology; Includes index

Title: Comparative test of centrifugal blowers
Creator: Griffiths, Francis H, Cummins, G. Fred
Date: 2009, 1911
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/comparativetesto00grif
Thesis (B.S.)--Armour Institute of Technology, 1911 B.S. in Mechanical Engineering, 1911

Title: Comparative tests on small steam pumps
Creator: Lewis, R. L., Monahan, J. E.
Date: 2009, 1908
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/comparativetests00lewi
Thesis (B.S.)--Armour Institute of Technology

Title: Comparative tests of small laminated and solid spruce beams for aeroplane construction
Creator: James, Sydney V
Date: 2009, 1911
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/comparativetests00jame
Thesis (B.S.)--Armour Institute of Technology; Bibliography: leaf 19

Title: Comparative test of cylinder lubricating oils
Creator: Hoffman, C. B., Jr, Hooper, B. G.
Date: 2009, 1907
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/comparativetesto00hoff
Thesis (B.S.)--Armour Institute of Technology

Title: The Engineering Significance of Limit Analysis
Creator: Hodge, Philip G. Jr.
Date: 2011-05-12, 1958-04
Publisher: Department of Mechanics, Illinois Institute of Technology
Description: By definition, the limit load on a structure is the unique magnitude of the given loads under which a structure can first deform if it is made...
Show moreBy definition, the limit load on a structure is the unique magnitude of the given loads under which a structure can first deform if it is made of a rigid-perfectly plastic material. The significance of the limit load for a structure made of a real material is discussed in relation to a simple truss.
Sponsorship: Contract No. Nonr 140604
This research was sponsored by the federal government. The appropriate Department of Defense database, DTIC Online Access Controlled, was consulted prior to submission to confirm that the report has no distribution limitations and may therefore be made available to the public online.
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