Engineering Commons^™

Structural Integrity And Fatigue Crack Propagation Life Assessment Of Welded And Weld-Repaired Structures, Mohammad Shah Alam

LSU Doctoral Dissertations

Structural integrity is the science and technology of the margin between safety and disaster. Proper evaluation of the structural integrity and fatigue life of any structure (aircraft, ship, railways, bridges, gas and oil transmission pipelines, etc.) is important to ensure the public safety, environmental protection, and economical consideration. Catastrophic failure of any structure can be avoided if structural integrity is assessed and necessary precaution is taken appropriately. Structural integrity includes tasks in many areas, such as structural analysis, failure analysis, nondestructive testing, corrosion, fatigue and creep analysis, metallurgy and materials, fracture mechanics, fatigue life assessment, welding metallurgy, development of repairing …

Fabrication Of High Aspect Ratio Vibrating Cylinder Microgyroscope Structures By Use Of The Liga Process, Yohannes Mamo Desta

LSU Doctoral Dissertations

Inertial grade microgyroscopes are of great importance to improve and augment inertial navigation systems based on GPS for industrial, automotive, and military applications. The efforts by various research groups worldwide to develop inertial grade microgyroscopes have not been successful to date. In 1994, the Department of Mechanical Engineering at Louisiana State University and SatCon Technology Corporation (Boston, Massachusetts) proposed a series of shock tolerant micromachined vibrating cylinder rate gyroscopes with aspect ratios of up to 250:1 to meet the needs of inertial navigation systems based on existing conventional vibrating cylinder gyroscopes. Each microgyroscope consisted of a tall thin shell metallic …

Effects Of Magnetic Field On Micro Flames, Sumathi Swaminathan

LSU Master's Theses

The effect of a gradient magnetic field on a diffusion micro flame i.e. C3H8/air flame has been systematically studied to comprehend their interaction. A non-uniform magnetic field was produced in the air gap of an electromagnet and the C3H8/air flame corresponding to various flow velocities was subjected to the non-uniform field. The influence of the operating conditions on the fundamental characteristics of the diffusion flame, such as the flame structure, temperature distribution and the morphology of the soot produced in these flames have been thoroughly investigated. The flame structure and its luminosity were found to be influenced and the flame …

Thermal Management Of The Lsu Micro Gas Chromatograph, Praveen K. Pasupuleti

LSU Master's Theses

Gas chromatography is a technique widely used for the separation and analysis of gas samples. Gas chromatographs are used for environmental maintenance, monitoring sophisticated biological analyses, and to separate components from a mixture of gases for mass spectrometer analysis. There has been a tremendous interest in miniaturization of gas chromatograph systems because of the potential for portability, faster response time, lower dead volume, lower power consumption, and lower cost of operation. Conventional gas chromatography keeps the column at a constant temperature during separation, which is called isothermal analysis. Temperature programming is a mode of gas chromatography in which the column …

Simulation Of A Micro Jet Cooling Array, Pierre Montanier

LSU Master's Theses

The new generation of electronic devices are more powerful, and they produce more heat. Hence, there is a need for micro cooling systems for removing the heat from these micro chips. This research focused on one micro cooling system-the micro jet cooling array. Some test simulations were made on a single jet cooling system. In addition, the inlet Reynolds number was varied in order to obtain the variation of the heat transfer coefficient. These simulations gave a basic idea of how the impingement cooling method works on the micro jet cooling array. Numerical simulations were made on the actual micro …

Nonlinear Control And Its Application To Active Tilting-Pad Bearings, Zhijun Cai

LSU Doctoral Dissertations

The drawbacks of active magnetic bearings are arousing interest in the adaptation of mechanical bearings for active use. A promising mechanical bearing candidate for active operation is the tilting-pad bearing. In this research, we introduce an active tilting-pad bearing with linear actuators that translate each pad. The use of feedback in determining the actuator forces allows for the automatic, continuous adjustment of the pad position during the machine operation. In this work, we develop the dynamic model of the active bearing system such that the actuator forces are the control inputs. The hydrodynamic force is modeled as a spring/damper-like force …

Analysis And Testing Of Waste Tire Fiber Modified Concrete, Gregory Marvin Garrick

LSU Master's Theses

There are very serious problems with the disposal of waste tires in the United States. Experiments were conducted to determine how the properties of concrete were affected by the inclusion of waste tires. Waste tires were used in the form of chips and fibers. The fibers were further divided into batches with different lengths to determine the effect of length has on the properties of concrete. There was a noticeable decline in the compressive strength of the concrete; however there was an increase in the toughness of the concrete. It was concluded that waste tire fibers were more suitable as …

Advanced Grid Stiffened Composite Structures, Dinesh Maricherla

LSU Master's Theses

In this study Advanced Grid Stiffened (AGS) composite structures are developed and analyzed for their mechanical properties. It is widely known that these structures possess light weight, high strength, and inherent impact resistance. Because of the advantages mentioned above, the AGS composite structures find many applications in aerospace, ship building and construction industries. The purpose of this study is to manufacture AGS composite structures and analyze AGS composite structures as reinforcement members. A FEA model is also developed and validated with the test results. Parametric analysis is also conducted to investigate the effects of different design parameters on these structures. …

Fracture Toughness Characterization Of Syntactic Foams, Vijay Gorugantu

LSU Master's Theses

Hollow particle filled polymeric materials called syntactic foams are used as core materials in sandwich composite structures. Syntactic foams find applications in aeronautical and space structures and therefore demand careful study and testing before they can be put to service. In the first part of this thesis work, syntactic foams are fabricated by varying the volume fraction of microballoons and also their density. Four different densities of microballoons are used ranging from 0.22 g/cc to 0.46 g/cc. The volume fraction of the microballoons is varied from 30% to 65%. A set of 3-point bending tests are conducted on these foam …

Modeling And Experimentation Of Drying Of Adipose Derived Adult Stem Cells, Surbhi Mittal

LSU Master's Theses

Development of protocols for storing desiccated cells at ambient temperatures offers tremendous economic and practical advantages over traditional storage procedures such as cryopreservation and freeze-drying. An integrated frame work of experimentation and modeling is adopted in the present work to develop procedures for storage of adult stem cells at ambient temperature. As a first step, we have measured the post-rehydration membrane integrity of two passages, Passage-0 (P0) and Passage-1 (P1), of human adipose-derived stem cells (hASCs). hASCs were dried using a convective stage at three different drying rates (slow, moderate and rapid) in D-PBS with trehalose (50 mM) and glycerol …

Pressure-Velocity Correlation Study On 1:50 Scale Model Of The Ttu Wind Engineering Research Field Lab Building, Praveen Kumar

LSU Master's Theses

The goal of the present study is to investigate the relationship between incident wind velocity fluctuations and the surface pressure fluctuations on the roof of a low rise building. The goal was fulfilled by studying the pressure velocity correlation on 1:50 scale model of a typical low rise building, the Wind Engineering Research Field Laboratory (WERFL) building located at Texas Tech University, Lubbock. The experimental study was carried out in the LSU Wind Tunnel Laboratory by simulating the boundary layer prevalent at the full-scale site. The velocity profile in the boundary layer was measured using the TSI Hot-Wire system with …

Cryopreservation Of Reproductive Cells And Tissues, Guanglei Li

LSU Master's Theses

Cryopreservation of reproductive cells and tissues is a useful technique to deliver intact genomes, maximize the distribution of favorable genes, control disease spread. It is widely applied to many fields such as biology, medicine, ecology and agriculture. To optimize the cryopreservation procedure, the biophysical responses of reproductive tissues at different cooling conditions and in different mediums must be clearly understood. Here we studied the biophysical response during freezing of: 1) bovine sperm frozen at a cooling rate of 20 ˚C/min in three media: without cryopreservation agents(CPAs), with 0.7 M glycerol, and with 0.7 M glycerol along with 1.5 mg/ml of …

On The Stability Of Rotor Bearing Systems Based On Hopf Bifurcation Theory, Jianke Wang

LSU Doctoral Dissertations

This research is aimed to establish instability criteria for a rotor-bearing system which consists of a rotor supported by two fluid-film journal bearings. The static and dynamic characteristics of rotor-bearing systems with consideration of turbulent effects are evaluated by applying the Hopf bifurcation theory (HBT) to the equations of motion. A method is developed for predicting the stability envelope of rotor-bearing systems using HBT. Results are compared with published literature obtained using a trial-and-error method. A method based on HBT is presented for predicting the occurrence of a hysteresis phenomenon, which is observed in experimental results dealing with the instability …

High Temperature Heat Exchanger Project: Quarterly Progress Report October 1, 2004 Through December 31, 2004, Anthony Hechanova

Publications (NSTD)

UNLV hosted an NHI Systems Interface Meeting on Dec. 16 and a UNLVRF HTHX Kickoff Meeting on Dec. 17. The purpose of the meetings was to coordinate the FY05 research and development effort of the UNLV Research Foundation portion of the Nuclear Hydrogen Initiative among the DOE, national program technical directors and the UNLVRF collaborators. Collaborators also had the opportunity to discuss their research program plan and update their progress. It was decided that these type of collaboration meetings were very useful and they will be held quarterly at the various collaborator sites. The next meeting will be in March …

Dec 2004, Tractor Museum

Lester F. Larsen Tractor Museum: Planning and Development Documents

Introductions Treasurer's Report Curator's Report

2004 Fall Engr333 Final Report On Co-Generation (Section A), Matt Dekam, Chris Wiesehan, Jason Flietstra, Jeremy Hanson, Brian Katerberg, Kevin Palmer, Aaron Svacha, Aaron Buys, Josh Blocker, Matt Vredevoogd, Andrew Huisjen, Thomas Totoe, Andy Vandermoren, Chris Vanroekel

ENGR 333

The goal of the project was to construct a realistic plan to get Calvin off the grid. This means that Calvin would own and operate on-site facilities that generate all the electricity consumed by the campus. Current peak load for the college is approximately three megawatts. Upon completion of the new recreation center and dining hall renovation, future load will climb to roughly five megawatts. As a result, the desired system to remove the college from the grid would provide five megawatts.

2004 Fall Engr333 Final Report On Wind Generation (Section B), Terry Austen, Kristin De Groot, Matt Ooms, Andy Van Noord, Kurt Koubal, Dan Kuiper, Andy Wermel, Ryan Dewall, Eddie Lucas, Dawn Svenkeson

ENGR 333

An energy savings plan for Calvin College has been developed. The plan suggests implementing a small-scale wind turbine pilot program and an energy usage awareness program (Powerful Savings). If implemented, this proposal could save around $6,400 annually with a payback period of 8 years.

Validation Of Energygauge® Usa Using The Hers Bestest, Florida Solar Energy Center, Philip W. Fairey

FSEC Energy Research Center®

This report presents results from the testing and validation of the EnergyGauge USA home energy rating software conducted using the HERS BESTEST procedures. The results show that EnergyGauge USA is an excellent and verifiable simulation program that is capable of meeting all national requirements for home energy rating software tools.

New Product Launch Decisions Under Competition And Uncertainty: A Real Options And Game-Theoretic Approach To New Product Development, James O. Ostler

Theses and Dissertations

New product development is central to many firms' future success. Not only as a means to continue to maintain their piece of the market, but product development can also be a strategic means for a company to diversify, and/or alter focus to adapt to changing market conditions.

Most of the research in new product development has been on how to do it cheaper and faster than the next guy. However, early commercialization does not guarantee a position of strength in the market. Failures of EMI in CT scanners and Xerox in personal computers illustrate that being first to market does …

Dynamic Stability And Handling Qualities Of Small Unmanned-Aerial-Vehicles Unmanned-Aerial-Vehicles, Tyler Michael Foster

Theses and Dissertations

General aircraft dynamic stability theory was used to predict the natural frequencies, damping ratios and time constants of the dynamic modes for three specific small UAVs with wingspans on the scale from 0.6 meters to 1.2 meters. Using USAF DatCom methods, a spreadsheet program for predicting the dynamic stability and handling qualities of small UAVs was created for use in the design stage of new small UAV concept development. This program was verified by inputting data for a Cessna-182, and by then comparing the program output with that of a similar program developed by DAR Corporation. Predictions with acceptable errors …

A Finite Element Simulation Of Temperature And Material Flow In Fricton Stir Welding, Mark J. Lasley

Theses and Dissertations

The purpose of this research was to use the Transvalor S.A. product, Forge3, to develop a finite element simulation of the friction stir welding process that improves the predictability of temperature evolution and material flow within the plunge portion of the process. Previous modeling created more heating within the billet than experimental results, probably due to the simplification of the simulation with adiabatic boundary conditions. More realistic tooling temperatures were included in this model as these affect heat evolution which is a determining factor in microcrystalline growth. These results were validated by experimental efforts using a billet and tooling instrumented …

The Effects Of Influent Debit On Hydrodynamic Characteristic Of Bojongsoang Facultative Pond: Without Wind Effects, Rositayanti Hadisoebroto, Suprihanto Notodarmojo

Makara Journal of Technology

The Effects of Influent Debit on Hydrodynamic Characteristic of Bojongsoang Facultative Pond: Without Wind Effects. The performance of facultative pond in Bojongsoang WWTP have reported to be unstable. One of the cause of the unstable performance is the hydrodynamic characteristics that not met the criterion. The improper hydrodynamic characteristics are included the existence of dead-zone, the short-circuiting, and the turbulence due to eddy current. The study was to analyze the effect of the influent debit variation on the hydrodynamic characteristics of the pond using mathematical model. The two-dimensional hydrodynamic model was built from two hydrodynamic equations which are continuity and …

Fuel Injection System For One Cylinder Motor Cycle Engine, Bambang Sugiarto

Makara Journal of Technology

Fuel Injection System for One Cylinder Motor Cycle Engine. Fuel injection has been developed for many years. But its common application is limited on car’s engine. With many reason fuel injection systems in motorcycle one cylinder engine has not been widely used yet. Fuel Injection System allows the amount of fuel, injected to be controlled appropriate to engine parameters such as engine speed, amount of air inducted to cylinder, temperature, for each cycle, over the entire engine operating conditions. This fuel injection research is done to find out the Volumetric Efficiency of the intake manifold system, the amount of fuel …

Influence Of Connection Placement To The Behavior Of Precast Concrete Exterior Beam-Column Joint, Elly Tjahjono, Heru Purnomo

Makara Journal of Technology

Influence of Connection Placement to the Behavior of Precast Concrete Exterior Beam-Column Joint. This paper presents an experimental study on the influence of connection placement to the behaviour of exterior beamcolumn joint of precast concrete structure under semi cyclic loading. Four half-scale beam-column specimens were investigated. Three beam-columns were jointed through connection that are placed in beam-column joint region and the forth is connected at the plastic hinge potensial region of the beam. Crack patterns, strength, stiffness and ductility of the test specimens have been evaluated. The test result indicated that all beam-column specimens show good ductility behavior.

Modelling And Simulation Of Packed Bed Catalytic Converter For Oxidation Of Soot In Diesel Powered Vehicles Flue Gas, Mohammad Nasikin, Praswasti P.D.K. Wulan, Vita Andrianty

Makara Journal of Technology

Modelling and Simulation of Packed Bed Catalytic Converter for Oxidation of Soot in Diesel Powered Vehicles Flue Gas. Diesel vehicle is used in Indonesia in very big number. This vehicle exhausts pollutants especially diesel soot that can be reduces by using a catalytic converter to convert the soot to CO2. To obtain the optimal dimension of catalytic converter it is needed a model that can represent the profile of soot weight, temperature and pressure along the catalytic converter. In this study, a model is developed for packed bed catalytic converter in an adiabatic condition based on a kinetic study that …

Optic Properties On Aggase2 Polycristal Fabrication, A. Harsono Soepardjo, I Dewa Made Janusetiawan

Makara Journal of Technology

Optic Properties on AgGaSe2 Polycristal Fabrication. Polycristal AgGaSe2, is compound (I-III-VI2) a semiconductor as basic material for thin film for solar cell. Polycristal was succesfully grown using Bridgmann Method, heated on sequential temperature treatment until 850°C and cooled down slowly until room temperature. Results observed were in the form of ingot (bars) with more or less 3 cm length and 13 mm in diameter. By using X-Ray Fefraction, composition obtained of each element (weight %) was Ag = 29,3996 %, Ga = 36,8123 % and Se = 30,29 % while using X-Ray Difraction lattice parameter obtained/calculated a = 4,4112 Å, …

A Method For Winding Advanced Composites Of Unconventional Shapes Using Continuous And Aligned Fibers, Abraham K. Allen

Theses and Dissertations

Advanced composites are extremely strong, rigid, and light, even when compared with advanced metals. Advanced composites are replacing high-tech metals as the material of choice for aerospace engineering. However, the processes used to manufacture advanced composites generally lose some of the properties of the materials by their process limitations.

One process that keeps the theoretically awesome qualities of the composite materials in tact is filament winding. Filament wound parts are used as rocket shells, bicycle frame tubes, drive shafts, pressure vessels, etc. Filament winding is an automated process and makes reliable parts to close tolerances. If a straight tube were …

Cold Climate Case Study; High Efficiency North Dakota Twin Homes, Florida Solar Energy Center, Dave Chasar

FSEC Energy Research Center®

The Eastern Dakota Housing Alliance has completed 8 of 20 planned multi-family and single-family dwellings on Selkirk Circle in Grand Forks, North Dakota. Four twin-home (duplex) units were completed in March of 2003 (Phase I) and four more identical units were completed in February of 2004 (Phase II). Four additional units (Phase III) are due for completion by mid-summer, 2004. Design assistance and performance testing were provided by the Building America Industrialized Housing Project with the goal of achieving up to 50% energy savings over the 1993 Model Energy Code.

To approach this level of savings, various envelope and equipment …

Comparison Of Sampling Methods For Flatness Evaluation Using Cmm, Ashish Singhal

All-Inclusive List of Electronic Theses and Dissertations

Efficient part feature verification using Coordinate Measuring Machine (CMM) requires efficient sample point selection as well as accurate zone fitting. This work deals with flatness tolerance evaluation and the Least- Square (LS) technique is used to compute tolerance zone. In regard to the sampling strategy there are several methods commonly employed in Coordinate Measuring Machine inspection literature. The appropriate method is selected according to the accuracy requirement, the geometry features of the work piece, and the condition of the machine producing the work piece. This research focuses on the five sampling methods: Hammersley sequence sampling, Halton-Zaremba sequence sampling, Random sampling, …

2004 Fall Student Seminar, Matt Dekam, Chris Wiesehan, Jason Flietstra, Jeremy Hanson, Brian Katerberg, Kevin Palmer, Aaron Svacha, Aaron Buys, Josh Blocker, Matt Vredevoogd, Andrew Huisjen, Thomas Totoe, Andy Vandermoren, Chris Vanroekel, Terry Austen, Kristin De Groot, Matt Ooms, Andy Van Noord, Kurt Koubal, Dan Kuiper, Andy Wermel, Ryan Dewall, Eddie Lucas, Dawn Svenkeson

ENGR 333

File for student presentation, given by students in the Fall 2004 class of ENGR333.