Mechanical Engineering Commons^™

Experimental Validation Of A Smart-Bias Active Magnetic Bearing Controller, Shailesh Pradhananga

LSU Master's Theses

Active magnetic bearings (AMBs) are being increasingly employed in the aerospace industry in a variety of devices including compressors, turbines, pumps, and flywheels. One application of great interest to future space missions is the Integrated Power and Attitude Control System (IPACS). The IPACS consists of an arrangement of flywheels that integrates the energy storage and attitude control functions into a single system; thereby, reducing the spacecraft mass, volume, launching cost, and maintenance. Like any energy storage system, flywheels need to be operated with low power losses. AMBs are ideally suited for flywheels because they eliminate mechanical losses (friction). Nevertheless, AMBs …

A Bio-Mems Device For Separation Of Breast Cancer Cells From Peripheral Whole Blood, Juan Feng

LSU Master's Theses

This work demonstrates the application of Bio-Micro Electro Mechanical System (Bio-MEMS) technology for early breast cancer detection and diagnosis. Early breast cancer detection and diagnosis typically uses conventional mammogram screening followed by biopsy, which can be problematic since mammography can only detect highly calcified tumors greater than 1 cm in size. A micro-device was developed to identify and specifically collect tumor cells of low abundance (1 tumor cell among 10⁷ normal blood cells) from circulating whole blood. By immobilizing anti-EpCAM (Epithelial Cell Adhesion Molecule) antibodies on polymer micro-channel walls by the chemical surface modification of PMMA, breast cancer cells …

Mesoscopic Simulation Of Abnormal Grain Growth, Rakesh Kumar Behera

LSU Master's Theses

Grain growth is the process that takes place during annealing of polycrystalline materials; its major feature is a systematic increase in grain size. Two different types of grain growth can be distinguished: the normal and abnormal grain growth. During normal grain growth, the microstructure exhibits a uniform increase in grain size with time and the grain size distribution follows the log-normal distribution with the grain sizes ranging from 0 - 2.2 times the average grain size (R). On the contrary, when the abnormal grain growth is the dominant mechanism, there are certain grains (abnormal grains) in the microstructure that grow …

Design Of A Microfabricated Device For Ligase Detection Reaction (Ldr), Dwhyte Omar Barrett

LSU Master's Theses

The Ligase Detection Reaction (LDR) is a mutation detection technique used to identify point mutations in deoxyribonucleic acid (DNA). Developed by Francis Barany and associates at Cornell University it is used to find specific low abundant point mutations that may lead to colorectal cancer in the early stages of disease development. The research objective was to design and manufacture a microscale Ligase Detection Reaction (LDR) device in polycarbonate. The LDR module will be incorporated with other microdevices such as: Continuous Flow Polymerase Chain Reaction (CFRCR) and Capillary Electrophoresis (CE) in modular lab-on-a-chip technology. In making the microdevice, the duration of …

Design, Fabrication And Thermomechanical Testing Of A Vertical Bimorph Sensor In The Wafer Plane, Madhulika Sathe

LSU Master's Theses

A bimetallic recurve device was designed, fabricated and tested as a temperature sensor. The device is to be used for sensing temperatures up to 300 C inside oil wells for downhole condition monitoring. Continuous downhole measurements at high temperatures and pressures are required to monitor conditions downhole instruments are exposed to during use. Currently mercury thermometers and resistive temperature detectors (RTD) are used for downhole temperature measurements. Microsensors have potential application downhole, due to their small size and inherent robustness. The principle of a bimetallic beam was used to measure temperature. A bimetallic beam deflects with changes in temperature due …

Study Of Characteristics Of Plasma Nitriding And Oxidation Of Superalloy In738lc, Mary Shanti Pampana

LSU Master's Theses

IN738LC is a nickel base superalloy, widely used in various applications in turbine engines at high temperatures. Its oxidation and nitriding characteristics were focused in this study. Oxidation kinetics of IN738LC in dry air was studied at selected temperatures, specially chosen depending on the chemical dynamics of the alloy at such high temperatures during annealing. Isothermal oxidation in dry air was carried out at 1000°C, 1090°C, 1140°C and 1190°C. XRD results indicated an interesting onset of preferred orientation in the ã’ depleted layer in all the samples. The XPS and XRD analyses revealed the main oxide phases present in the …

The Spectral Conforming Model And Its Applications, Jaeho Shim

LSU Doctoral Dissertations

It has been observed that finite element or finite difference model of order can approximate with fair accuracy less than one-third of the eigenvalues of the underlying continuous system corresponding to the low spectrum. The new discrete model, namely the spectral conforming model, is developed to predict the eigenvalues of continuous systems in both the low and high spectra. The spectral conforming models are developed using an inverse vibration method. The classical vibration problem is the direct method. In the direct approach, the characteristic behaviors of the system, i.e. frequency response, natural frequency, and steady state response are analyzed and …

Algorithms For Autonomous Tandem Operation Of A Dual M113 System, Jared L. Dinkel

Dissertations, Master's Theses and Master's Reports - Open

In mid-July 2003, the U.S. Army Tank-Automotive & Armaments Command (TACOM) performed a series of experiments at Keweenaw Research Center (KRC), with a remote operated mine roller system. This system, named Panther Lite, consists of two M113 Armored Personnel Carriers (APC’s) connected by a Tandem Vehicle Linkage Assembly (TVLA). The system has three sets of mine rollers, two of which are connected to the front of the lead vehicle with one set trailing from the trail vehicle. Currently, the system requires two joystick controllers. One regulates the braking of the tracks, throttle, and transmission of the lead vehicle and …

Microscale Investigation Of Thermo-Fluid Transport In The Transition Fil, Region Of An Evaporating Capillary Meniscus Using A Microgravity Environment, Kenneth D. Kihm, Jeffrey S. Allen, Kevin P. Hallinan, David M. Pratt

Mechanical and Aerospace Engineering Faculty Publications

In order to enhance the fundamental understanding of thin film evaporation and thereby improve the critical design concept for two-phase heat transfer devices, microscale heat and mass transport is to be investigated for the transition film region using state-of-the-art optical diagnostic techniques. By utilizing a microgravity environment, the length scales of the transition film region can be extended sufficiently, from submicron to micron, to probe and measure the microscale transport fields which are affected by intermolecular forces. Extension of the thin film dimensions under microgravity will be achieved by using a conical evaporator made of a thin silicon substrate under …

Estimating Energy Savings In Compressed Air Systems, Chris Schmidt, J. Kelly Kissock

Mechanical and Aerospace Engineering Faculty Publications

Compressed air is typically one of the most expensive utilities in an industrial facility. As a result, potential savings opportunities are aggressively sought out and identified. Once identified, projected energy savings must be calculated in order to justify the cost of implementing the savings opportunity. It is important to calculate projected energy and cost savings as accurately as possible. Unfortunately, savings are frequently overestimated because the methods used to estimate savings neglect to consider important factors such as compressor control and type, storage, and multiple compressor operation.

In this paper, a methodology is presented for modeling air compressor performance and …

Effects Of Corrosion Prevention Compounds And Overload Induced Residual Stress Field On Fatigue Life In Aluminum Alloy, Jin Hee Park

LSU Master's Theses

Corrosion-Prevention Compounds (CPC) are commonly used to prevent corrosion in the aircraft industry. The presence of corrosive environment (salt-fog, water-fog, even dry air) on aircraft structures has detrimental effects on the integrity of aircraft components which reduces the fatigue life and may accelerate the crack growth rate in the structures. This thesis work is aimed at identifying the effect of CPC and corrosion fatigue on the fatigue life of test specimen. This study describes the results of an experimental study on aluminum alloy 2024-T3 with center-crack specimen to investigate the effect of CPC on fatigue life. Generally, these compounds contain …

A Novel Mechanical Seal Design With Superior Thermal Characteristics, Anoop Kumar Somanchi

LSU Master's Theses

A mechanical face seal is an important component of variety of pumps used in chemical, petrochemical and process industry. The primary function of a mechanical seal is to prevent leakage of the process fluid from the pump housing and shaft to the environment. The factors that affect the performance of a mechanical seal to leak are friction, wear and its thermal characteristics. Improving upon the thermal characteristics of a mating ring in a mechanical seal would enhance its performance. Implanting a heat exchanger in the mating ring hold great promise for improving the performance of mechanical seals from the viewpoint …

Optimization Of Thermal Interface Materials For Electronics Cooling Applications, Vishal Singhal, Thomas Siegmund, Suresh V. Garimella

School of Mechanical Engineering Faculty Publications

Thermal interface materials (TIMs) are used in electronics cooling applications to decrease the thermal contact resistance between surfaces in contact. A methodology to determine the optimal volume fraction of filler particles in TIMs for minimizing the thermal contact resistance is presented. The method uses finite element analysis to solve the coupled thermo-mechanical problem. It is shown that there exists an optimal filler volume fraction which depends not only on the distribution of the filler particles in a TIM but also on the thickness of the TIM layer, the contact pressure and the shape and the size of the filler particles. …

Optimisation Of Heat Transfer And Fluid Flow In The Cooling Of Building Integrated Photovoltaic Facades., Eoin Patrick Hodge

Theses

The aim of this research was to explore the effects of mature and developing technologies from aeronautical industries such as impingement and film cooling, and electronic cooling techniques, in the setting up of different laminar and turbulent flow regimes on PV cooling duct heat transfer rates, with air flow as that brought about with natural buoyancy effects in a vertical building facade. The problem of efficiency losses in PV panels, due to overheating, is one of the factors restricting the development and use of this renewable power source. PV panels can experience very high temperatures, due to the heat input …

Nebraska Summary 446: Agco Rt135 Powermaxx Diesel, Nebraska Tractor Test Lab

Nebraska Tractor Tests

No abstract provided.

Nebraska Summary 521: Agco Rt140a Cvt Diesel, Nebraska Tractor Test Lab

Nebraska Tractor Tests

No abstract provided.

Nebraska Summary 447: Agco Rt150 Powermaxx Diesel, Nebraska Tractor Test Lab

Nebraska Tractor Tests

No abstract provided.

Test 1845: John Deere 9620t 18 Speed, Nebraska Tractor Test Lab

Nebraska Tractor Tests

No abstract provided.

Tests 2156 & 2157: Case Ih Jx 1060c Diesel, Nebraska Tractor Test Lab

Nebraska Tractor Tests

No abstract provided.

Tests 2278 & 2319: Case Ih Jx 1100u Diesel, Nebraska Tractor Test Lab

Nebraska Tractor Tests

No abstract provided.

Test 2228: Case Ih Mxu115 Limited Diesel, Nebraska Tractor Test Lab

Nebraska Tractor Tests

No abstract provided.

Test 1836a: Case Ih Dx48 Diesel, Nebraska Tractor Test Lab

Nebraska Tractor Tests

No abstract provided.

Test 1837: Case Ih Dx 55 Diesel, Nebraska Tractor Test Lab

Nebraska Tractor Tests

No abstract provided.

Tests 2248 & 2272: New Holland Tl 90a Diesel, Nebraska Tractor Test Lab

Nebraska Tractor Tests

No abstract provided.

Tests 2166 & 2167: New Holland Tn70da Diesel, Nebraska Tractor Test Lab

Nebraska Tractor Tests

No abstract provided.

Tests 2130 & 2151: New Holland Tn75a Diesel, Nebraska Tractor Test Lab

Nebraska Tractor Tests

No abstract provided.

Tests 2131 & 2150: New Holland Tn75da Diesel, Nebraska Tractor Test Lab

Nebraska Tractor Tests

No abstract provided.

Test 2203: New Holland Ts135a Diesel, Nebraska Tractor Test Lab

Nebraska Tractor Tests

No abstract provided.

Test 1837a: New Holland Tc 55da Diesel, Nebraska Tractor Test Lab

Nebraska Tractor Tests

No abstract provided.

Tests 2288 & 2289: Challenger Mt455b Diesel, Nebraska Tractor Test Lab

Nebraska Tractor Tests

No abstract provided.