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Comparison Of Carbon Steel And Composite Side Wall Of Light Rail Vehicle By Finite Element Analysis, Dilraj Singh 2018 University of Texas at Arlington

Comparison Of Carbon Steel And Composite Side Wall Of Light Rail Vehicle By Finite Element Analysis, Dilraj Singh

Mechanical and Aerospace Engineering Theses - Archive

A Railroad car is a vehicle used for carrying passengers and cargo. In the modern era, rail vehicles are designed as lightweight structures with the aim to minimize mass, operational energy demands, and CO2 emissions. Light rail vehicle is used at street level where they have direct contact with normal traffic and have a short distance between stations. In order to reduce dwell time at stops, and so, the vehicle can accelerate and deaccelerate easily, weight should be less and that is why low floor design is adopted these days. The sidewall is a crucial part of the car body …


Airflow Path And Flow Pattern Analysis Of Sub-Micron Particulate Contaminants In A Data Center With Hot Aisle Containment System Utilizing Direct Air Cooling, Satyam Saini 2018 University of Texas at Arlington

Airflow Path And Flow Pattern Analysis Of Sub-Micron Particulate Contaminants In A Data Center With Hot Aisle Containment System Utilizing Direct Air Cooling, Satyam Saini

Mechanical and Aerospace Engineering Theses - Archive

The percentage of the energy used by data centers for cooling their equipment has been on the rise. With it has been the necessity for exploring new and more efficient methods, both from an engineering as well as business point of view, to contain this energy demand. The PCB boards are becoming more densely populated with multitude of smaller hardware on them, thereby, increasing its cooling requirements. Literature suggests that almost 40% of the total energy consumption in a typical Data Center is used for cooling purposes. Air cooling has always been the first choice for IT companies to cool …


Experimental Characterization Of Vertically Split Distribution Wet- Cooling Media Used In Direct Evaporative Cooling Of Data Center, Ahmed Al Khazraji 2018 University of Texas at Arlington

Experimental Characterization Of Vertically Split Distribution Wet- Cooling Media Used In Direct Evaporative Cooling Of Data Center, Ahmed Al Khazraji

Mechanical and Aerospace Engineering Theses - Archive

When operating in direct evaporative cooling (DEC) mode, the amount of moisture added to a system can be controlled by frequently modulating water supply to the wet cooling media. Though many challenges arise due to geographical and site conditions, this concept can be applied to data centers to serve as a cost-effective alternative for maintaining the operating temperature of the facility at any weather condition. However, this method results in scale and mineral build up on the media because of an irregular water distribution. To prevent the scale formation, the operators allow the water supply continuously on the cooling media …


Investigation On Effective Modulus And Stress Concentration Factor Of 3d Reinforced Composite By Finite Element Analysis Method, Chandra Bhaskar Reddy Pittu 2018 University of Texas at Arlington

Investigation On Effective Modulus And Stress Concentration Factor Of 3d Reinforced Composite By Finite Element Analysis Method, Chandra Bhaskar Reddy Pittu

Mechanical and Aerospace Engineering Theses - Archive

Micromechanics of Composites aims to analyze the localized stresses inside any given constituents of the composite structure. This Thesis is focused on Calculating the effective modulus and the Stress concentration factor of the 3D straight Fiber Composite using Finite Element(FE). The compressive and a Shear response of a 3D Straight fiber composite comprising three directional E Glass Fibers reinforced in an epoxy matrix is analysed. This result is the 10% of overall Composite Ductility and a 10% of overall Shear displacement load in the orthogonal directions. FE calculations are reported to analyse the response of 3d reinforcement as of with …


Optimization Of Heating, Ventilation, And Air-Conditioning (Hvac) Chilled Water Plant Systems, Cliff Odhiambo Nudi 2018 University of Texas at Arlington

Optimization Of Heating, Ventilation, And Air-Conditioning (Hvac) Chilled Water Plant Systems, Cliff Odhiambo Nudi

Mechanical and Aerospace Engineering Theses - Archive

Heating, Ventilation, and Air-conditioning accounts for about 60% of the total energy consumed in commercial facilities including office buildings, hospitals, retail stores, warehouses, campuses, manufacturing facilities, medical facilities, etc. As the cost of electricity and energy continue to rise, building owners and facility managers continue to witness a rise in the Total Cost of Ownership. Chilled water plant system is the largest consumer of energy in HVAC system consuming 75% of the total energy used in HVAC according to the Department of Energy. Operating chilled water plant systems at the recommended AHRI Standard 550/590 for performance rating of water chilling …


Design And Experimental Study Of Hydrostatic Thrust Air Foil Bearing, Myong Sok Song 2018 University of Texas at Arlington

Design And Experimental Study Of Hydrostatic Thrust Air Foil Bearing, Myong Sok Song

Mechanical and Aerospace Engineering Theses - Archive

Oil-free bearing technology has several advantages over conventional oil-lubricated bearings. These advantages include high-speed operation, reduced weight, and increased reliability. Consequently, oil-free technology is expected to replace conventional bearings in a variety of applications. However, many challenges need to be addressed for widespread adoption of oil-free technology such as lower load capacity during start/stop and issues with controlling temperature. Thrust bearings, unlike their radial counterparts, are used for supporting axial loads and have become more important in recent years because of layout requirements other than double overhang configuration gaining consideration for specialized applications. Moreover, the requirements are demanding more extreme …


Simulation, Control And Testing Of A Custom 5-Dof Robotic Manipulator System, Roopak M. Karulkar 2018 University of Texas at Arlington

Simulation, Control And Testing Of A Custom 5-Dof Robotic Manipulator System, Roopak M. Karulkar

Mechanical and Aerospace Engineering Theses - Archive

Open chain manipulators are a well posed problem, however it was necessary to build a system customized to meet the needs of the Unmanned Ground Vehicle developed in the Aerospace Systems Laboratory. Considering that there are multiple such small ground vehicles, the main design constraint on the system was to be modular and lightwieght to enable quick swapping from both, a hardware and a software point of view. The purpose of this thesis is design, simulation and control a modular 5-Degree-of-Freedom manipulator with versatility in end effector configuration. This was achieved through the Robot Operating System which brings a high …


Experimental Investigation Of Thermophysical Properties Of Enhanced Nitrate Salt Nanofluids For Thermal Energy Storage (Tes) In Concentrated Solar Power (Csp) Systems, Vamsi Kiran Eruvaram 2018 University of Texas at Arlington

Experimental Investigation Of Thermophysical Properties Of Enhanced Nitrate Salt Nanofluids For Thermal Energy Storage (Tes) In Concentrated Solar Power (Csp) Systems, Vamsi Kiran Eruvaram

Mechanical and Aerospace Engineering Theses - Archive

The main source for energy production right now is from thermal, nuclear energy. But in the near future we might have crisis of coal so we need alternate renewable source for energy production the solution for that is sun, since solar energy is renewable and abundantly available. Concentrated solar power (CSP) technologies is one of the best solution to overcome this energy crisis, because it works from solar energy. If the CSP is incorporated with thermal energy storage (TES) we can produce energy even during night. TES with 15-hour storage capacity (Gemasolar) is already commercialized to operate a CSP plant …


Additive Manufacturing Process Investigation For The Fabrication Of Composite Scaffolds For Soft Tissue Application, Parimal Patel 2018 University of Texas at Arlington

Additive Manufacturing Process Investigation For The Fabrication Of Composite Scaffolds For Soft Tissue Application, Parimal Patel

Mechanical and Aerospace Engineering Theses - Archive

Additive manufacturing has been investigated and employed in the bio-medical domain for the fabrication of various devices and scaffolds. In various soft tissue engineering applications, multi-functional multi-material scaffolds are required for cell proliferation, structural integrity, bio-compatibility and tissue regeneration. In this research, an additive manufacturing methodology is developed to allow the fabrication of bio-composite scaffolds using a multi-modality in-house built platform. The researched materials for printing are Poly-L-Lactic Acid (PLLA) and a newly developed photo-curable radiopaque polymer called Rylar (Poly glycerole sebacate fumarate gadodiamide) mixed with a cross-linking agent Poly (Ethylene glycol) diacrylate (PEGDA). The developed methodology uses a Fused …


Reliability Of A 2.5d Tsv Package, Neha Vinayak Gaikwad 2018 University of Texas at Arlington

Reliability Of A 2.5d Tsv Package, Neha Vinayak Gaikwad

Mechanical and Aerospace Engineering Theses - Archive

In the recent years, the Through Silicon Vias (TSVs) are helping a huge variety of the 3D IC and the 2.5D IC packaging applications to try to fulfill their requirements of functionality and higher connectivity at the expense of lower power consumption and minimum heat dissipation. The TSVs offer great interconnect density, high device density, short connection paths, great space efficiency and high interconnect bandwidth. The basic difference between a 3D TSV package and a 2.5D TSV package is that the 2.5D one interconnects the dies side by side on a silicon interposer, over its entire length. The interposer, placed …


Mass Fabrication & Evolution Of Beads On Fiber, Kirthika Suresh 2018 University of Texas at Arlington

Mass Fabrication & Evolution Of Beads On Fiber, Kirthika Suresh

Mechanical and Aerospace Engineering Theses - Archive

In this work, we systematically explore the relation between the coating speeds and the finally formed liquid beads on fiber. The main focus of the paper lies with contact angle, length and height of beads on fiber and the fiber drawing velocity. For this purpose, free energy variation method is applied, based upon which the boundary conditions for the beads-on-fiber system and governing equations were re-derived. A combination of both, first and the second kind of the Legendre’s elliptical functions are used to determine the geometrical shape of the beads. Contact angle is extracted from the experimental data by using …


Predicting Mechanical Behavior Of 3d Printed Structures Using Mechanics Of Composites And Fracture, Megha Tangri 2018 University of Texas at Arlington

Predicting Mechanical Behavior Of 3d Printed Structures Using Mechanics Of Composites And Fracture, Megha Tangri

Mechanical and Aerospace Engineering Theses - Archive

Recently, additive manufacturing, or 3D printing as it is more commonly called, has taken a big leap in the manufacturing industry. This technology is rapidly moving from prototyping to manufacturing using metals, polymers, concrete and even composites. Unlike subtractive methods of manufacturing, additive manufacturing can be used to manufacture parts with highly directional mechanical properties. This research focuses on predicting tensile failure of 3D printed polymer structures in different raster orientations using composites lamination theory. Previously it was found experimentally that tensile strengths of 3D printed specimens decrease when raster orientations changes from 0° to 90°. The proposed model developed …


Numerical Simulation Of Unsteady Normal Detonation Combustion, Ajjay Omprakas 2018 University of Texas at Arlington

Numerical Simulation Of Unsteady Normal Detonation Combustion, Ajjay Omprakas

Mechanical and Aerospace Engineering Theses - Archive

The objective of this research is to simulate normal detonation combustion which is a mode of operation for a Pulsed Detonation Engine (PDE). A supersonic flow with stoichiometric hydrogen-air mixture is made to impinge on a wedge, thus resulting in increasing the temperature and pressure across a shock wave leading to the formation of detonation wave. Different modes of the operations can be simulated by varying the incoming Mach number, pressure, temperature and equivalence ratio. For the case of normal detonation wave mode which is an unsteady process, after the detonation being initiated due to the shock induced by the …


Experimental And Analytical Study Of A Self-Regulated Flow Control Device Developed For Dynamic Cold-Plates To Cool High-Power Density Multi-Chip Modules, Rishi Ruben Palanikumar 2018 University of Texas at Arlington

Experimental And Analytical Study Of A Self-Regulated Flow Control Device Developed For Dynamic Cold-Plates To Cool High-Power Density Multi-Chip Modules, Rishi Ruben Palanikumar

Mechanical and Aerospace Engineering Theses - Archive

Modern high-power density modules often demand high amounts of power be invested in their cooling processes. Uneven heating at the chip level creates hotspots and temperature gradients across the module. A very effective way to conserve pumping power and address hotspots on the module is by targeted delivery of liquid coolant. One way to enable such targeted delivery of coolant is by using dynamic cold-plates (DCP) coupled with self-regulated flow control devices. This paper deals with the optimization and characterization of one such flow control device (FCD). The self-regulated FCD is actuated by a heat reactive shape memory alloy, Nitinol. …


Comparison Of Nonlinear Filters For An Autonomous Lunar Mission Using Existing Navigation Techniques, Matthew David Shaver 2018 University of Texas at Arlington

Comparison Of Nonlinear Filters For An Autonomous Lunar Mission Using Existing Navigation Techniques, Matthew David Shaver

Mechanical and Aerospace Engineering Theses - Archive

Navigation systems play an important role for autonomous spacecraft. Earth based navigation systems such as GPS provide accurate positioning for orbiting spacecraft. In the case of lunar orbit, GPS is not available so other navigation techniques have to be used. This thesis proposes a novel idea to use Laser Ranging Retroreflectors, placed on the Moon's surface during the Apollo program, as a means of providing position information to an orbiting autonomous spacecraft. An Inertial Navigation System consisting of fusion of LRRR position data and Inertial Measurement Unit providing gyro and accelerometer data will be utilized during orbit about the Moon. …


Impact Of Thermal Aging On Crack Growth Behavior Of Lead Free Solder Interconnects, Anuraag Girish Karnik 2018 University of Texas at Arlington

Impact Of Thermal Aging On Crack Growth Behavior Of Lead Free Solder Interconnects, Anuraag Girish Karnik

Mechanical and Aerospace Engineering Theses - Archive

Reliability assessment helps in better performance of electronic packages. This also helps electronic device manufacturing company as well as the users to evaluate the life of any device. The microstructure, mechanical response, and failure behavior of Pb-free solder joints in electronic assemblies are constantly evolving when exposed to isothermal aging and/or thermal cycling environments. Due to reflow process or exposure to harsh environment conditions, packages are subject to fatigue loads which can accelerate crack growth in the solder interconnects. But, some material after aging get hardened and decrease in plastic deformation capacity. This effect sometimes leads to better crack resistance …


Finite Element Analysis Of Composite Reactor Pressure Vessel, Tejas Vasant Mhetre 2018 University of Texas at Arlington

Finite Element Analysis Of Composite Reactor Pressure Vessel, Tejas Vasant Mhetre

Mechanical and Aerospace Engineering Theses - Archive

Reactor Pressure Vessel is the container designed to hold gases or liquids above atmospheric pressure. The focus of this study is to develop Finite Element Model to predict the performance of composite reactor pressure vessel subjected to extreme pressure and temperature and compare with pressure vessel manufactured using conventional materials. In the first part of the study, a pressure vessel system with Carbon steel material under design pressure and temperature have been analyzed for stresses, deformation and Safety Factor. Various loading cases have been discussed during the analysis of pressure vessel. Composite materials have been a suitable replacement to the …


Development And Validation Of The Deliquescent Relative Humidity Test Method For The Accumulated Particulate Matter Found In A Data Center Utilizing An Airside Economizer, Roshan Anand 2018 University of Texas at Arlington

Development And Validation Of The Deliquescent Relative Humidity Test Method For The Accumulated Particulate Matter Found In A Data Center Utilizing An Airside Economizer, Roshan Anand

Mechanical and Aerospace Engineering Theses - Archive

Data centers are virtual or physical infrastructure utilized by enterprises to house computer, server and networking systems and other vital components for the needs of the company’s information technology mainly serving the purpose of storing, processing and serving large amounts of mission critical data to clients. As data centers house a network’s most critical systems and are extremely vital for the continuity of daily operations, every organization prioritizes the reliability and security of data centers and their information. A remarkable amount of data center energy is consumed in eliminating the heat generated by Information Technology (IT) equipment to maintain and …


Accelerated Thermal Cycling Of Printed Circuit Board For Single Phase Immersion Cooling Systems, Surya Duraisamy Asokan 2018 University of Texas at Arlington

Accelerated Thermal Cycling Of Printed Circuit Board For Single Phase Immersion Cooling Systems, Surya Duraisamy Asokan

Mechanical and Aerospace Engineering Theses - Archive

The adoption of immersion cooling of data center over conventional air-cooling is one among the more up to date advances that individuals have begun embracing to. Acknowledgement of Single phase Liquid Immersion cooling (Sp-LIC) of Information Technology equipment gives proficient cooling frameworks and significant vitality energy savings. This study centers on the unwavering reliability assessment in analyzing the material property of Printed Circuit Board (PCB) and performing Scanning Electron Microscope (SEM) scanning of the samples for any penetration of liquids into PCB. The Accelerated Thermal Cycling (ATC) test in view of ATC JEDEC is relevant just for air cooling. The …


Human Robot Interaction With Cloud Assisted Voice Control And Vision System, Ravi Patel 2018 University of Texas at Arlington

Human Robot Interaction With Cloud Assisted Voice Control And Vision System, Ravi Patel

Mechanical and Aerospace Engineering Theses - Archive

The objective of this research is to investigate a way of interaction between humans and robots, which is through voice or speech commands. A Biomimetic Artificial Hand (BAH) is used as a platform to perform grasping tasks using human voice as an interacting and instructing medium between humans and robots. It is a hands-free approach of issuing commands to the BAH since it does not require the user to wear any specialized equipment. Previous research has shown difficulties in recognizing more than one word, database management for stored voice, and requirement of sufficient computing power. National Instruments software LabVIEW and …


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