High Strain Rate Experiments Of Energetic Material Binder,
2016
Purdue University
High Strain Rate Experiments Of Energetic Material Binder, Roberto Rangel Mendoza, Michael Harr, Weinong Chen
The Summer Undergraduate Research Fellowship (SURF) Symposium
Energetic materials, in particular HMX, is widely used in many applications as polymer bonded explosives (PBX) and rocket propellant. However, when damaged, HMX is known to be an unstable substance which renders it a hazardous material and in some cases unreliable. Finding critical mechanical conditions at high rates that render various forms of energetic materials as unreliable would be vital to understand the effects that vibrations and compression forces have on energetic materials. A better understanding would enable the ability to develop improvements in the manufacturing of PBX and rocker propellant. The method utilized to evaluate the mechanical properties of …
An Experimental Investigation Of Self-Excited Combustion Dynamics In A Single Element Lean Direct Injection (Ldi) Combustor,
2016
Purdue University
An Experimental Investigation Of Self-Excited Combustion Dynamics In A Single Element Lean Direct Injection (Ldi) Combustor, Rohan M. Gejji
Open Access Dissertations
The management of combustion dynamics in gas turbine combustors has become more challenging as strict NOx/CO emission standards have led to engine operation in a narrow, lean regime. While premixed or partially premixed combustor configurations such as the Lean Premixed Pre-vaporized (LPP), Rich Quench Lean burn (RQL), and Lean Direct Injection (LDI) have shown a potential for reduced NOx emissions, they promote a coupling between acoustics, hydrodynamics and combustion that can lead to combustion instabilities. These couplings can be quite complex, and their detailed understanding is a pre-requisite to any engine development program and for the development of predictive capability …
Particle Modeling Of Non-Equilibrium Field Emission Driven Rf Microplasmas,
2016
Purdue University
Particle Modeling Of Non-Equilibrium Field Emission Driven Rf Microplasmas, Siva Sashank Tholeti
Open Access Dissertations
Non-equilibrium microplasmas at atmospheric pressures have been investigated for active flow control, micropropulsion and electronic display applications to name a few. The operational voltages for these microplasmas are on the order of kilovolts. When the electric field at the electrodes reaches GV/m or tens of GV/m either due to reduced interelectrode spacing and surface irregularities or due to carefully designed nanostructures on the electrodes, quantum processes such as field emission and field ionization come into effect. These can potentially reduce the operational voltages of microplasma devices by an order of magnitude. Due to the rarefied and non-equilibrium nature of these …
On The Enhancement Of Thermo-Mechanical And Impact Reliability Of Passive And Active Microelectronic Devices,
2016
University of Texas at Arlington
On The Enhancement Of Thermo-Mechanical And Impact Reliability Of Passive And Active Microelectronic Devices, A R Nazmus Sakib
Mechanical and Aerospace Engineering Dissertations - Archive
Microelectronic devices are an essential part of human life. The idea of Internet of Things (IoT) where all the everyday devices will be connected with each other transmitting information and operating on their own is becoming very popular. A silicon chip which has millions of transistors in it, has been the heart and brain of the everyday components ranging from personal entertainment, communication to Automotive ECU (electronic control Unit), and health care management systems to home security systems. Every aspect of modern human experience is dependent on this tiny silicon chip. Microelectronic devices can be divided into two broad categories …
Investigation Of Exothermic Reaction Dynamics Via Computational Fluid Dynamics Coupled With A Feedback Controller,
2016
University of Texas at Arlington
Investigation Of Exothermic Reaction Dynamics Via Computational Fluid Dynamics Coupled With A Feedback Controller, Siusan Choi
Mechanical and Aerospace Engineering Dissertations - Archive
The control of reaction temperature under continuous flow conditions is important in a variety of chemical manufacturing industries. For many reactions, operating at off-design temperatures can result in the production of undesired products, reduced feedstock conversion and, in some cases, reduced catalyst lifetime. In many exothermic reactions, maintaining a desired set point temperature at high reactant flow rates becomes challenging if the chemical kinetics exhibit highly non-linear behavior. In these situations, the interaction between commonly used linear controllers and the physical system can lead to unexpected dynamic response and undesired swings in reaction temperature. In this research, a computational model …
General Solutions To Temperature Distribution In Orthotropic Systems Subject To Variable Heat Transfer And Biological Systems During Bioheat Transfer,
2016
University of Texas at Arlington
General Solutions To Temperature Distribution In Orthotropic Systems Subject To Variable Heat Transfer And Biological Systems During Bioheat Transfer, Daipayan Sakar
Mechanical and Aerospace Engineering Dissertations - Archive
Bioheat transfer is the phenomenon of heat transfer in biological systems where the dominant modes of heat transfer are conduction and advection. Other factors such as rate of metabolism that are unique to biological systems contribute significantly towards bioheat transfer. In the present work, the Pennes bioheat equation has been solved for a multilayer system to derive steady state and transient temperature solutions in the multilayer skin tissue with a tumor. In nanoparticle based hyperthermia therapy, the body temperature elevates from the physiological core body temperature, 37 deg. C. Analytical solutions for three different therapeutic techniques have been developed to …
Integration Of A Portfolio-Based Approach To Evaluate Aerospace R&D Problem Formulation Into A Parametric Synthesis Tool,
2016
University of Texas at Arlington
Integration Of A Portfolio-Based Approach To Evaluate Aerospace R&D Problem Formulation Into A Parametric Synthesis Tool, Amit R. Oza
Mechanical and Aerospace Engineering Dissertations - Archive
The focus of this study is to improve R&D effectiveness towards aerospace and defense planning in the early stages of the product development lifecycle. Emphasis is on: correct formulation of a decision problem, with special attention to account for data relationships between the individual design problem and the system capability required to size the aircraft, understanding of the meaning of the acquisition strategy objective and subjective data requirements that are required to arrive at a balanced analysis and/or “correct” mix of technology projects, understanding the meaning of the outputs that can be created from the technology analysis, and methods the …
Performance Analysis, Dynamic Simulation And Control Of Mass-Actuated Airplane,
2016
University of Texas at Arlington
Performance Analysis, Dynamic Simulation And Control Of Mass-Actuated Airplane, Sukru Akif Erturk
Mechanical and Aerospace Engineering Dissertations - Archive
The control of space, aerial and underwater vehicles requires moment generation mechanisms to change their orientation. In addition to or in place of conventional moment generation actuators, internally moving-mass actuation has been proposed and/or used for such vehicles. The primary principle for mass-actuation is to reposition gravitational force to change the associated moment while the secondary effect may come from the inertial force due to the motion of the masses. Recent development/miniaturization in flight control sensor, computing and actuation, and electric motors and expansion of applications for small UAV (Unmanned Aerial Vehicle) offer a potential for implementation of internal mass-actuation …
Complex Multidisciplinary System Composition For Aerospace Vehicle Conceptual Design,
2016
University of Texas at Arlington
Complex Multidisciplinary System Composition For Aerospace Vehicle Conceptual Design, Alexis R. Gonzalez
Mechanical and Aerospace Engineering Dissertations - Archive
Although, there exists a vast amount of work concerning the analysis, design, integration of aerospace vehicle systems, there is no standard for how this data and knowledge should be combined in order to create a synthesis system. Each institution creating a synthesis system has in house vehicle and hardware components they are attempting to model and proprietary methods with which to model them. This leads to the fact that synthesis systems begin as one-off creations meant to answer a specific problem. As the scope of the synthesis system grows to encompass more and more problems, so does its size and …
Experimental Investigation Of Methane Reformer With A Continuous Flow Reactor,
2016
University of Texas at Arlington
Experimental Investigation Of Methane Reformer With A Continuous Flow Reactor, Xiao Zhang
Mechanical and Aerospace Engineering Dissertations - Archive
Over the decades, seeking for an alternative energy source has been more and more significant because of increasing demand with rapid industry expansion. Liquid hydrocarbon from Fischer-Tropsch process is considered as an alternative fuel source because the product is considered as subtle for petroleum-derived. Syngas as feedstock for F-T process plays a crucial role in liquid hydrocarbon production. Among several commercial and experiment technologies, the most common technology for syngas production is natural gas reforming. The product from reforming process has proper carbon monoxide/hydrogen ratio for direct application in F-T synthesis. Meanwhile, combined carbon dioxide into reforming reaction has attracted …
Complex Multidisciplinary Systems Decomposition For Aerospace Vehicle Conceptual Design And Technology Acquisition,
2016
University of Texas at Arlington
Complex Multidisciplinary Systems Decomposition For Aerospace Vehicle Conceptual Design And Technology Acquisition, Amen Omoragbon
Mechanical and Aerospace Engineering Dissertations - Archive
Although, the Aerospace and Defense (A&D) industry is a significant contributor to the United States’ economy, national prestige and national security, it experiences significant cost and schedule overruns. This problem is related to the differences between technology acquisition assessments and aerospace vehicle conceptual design. Acquisition assessments evaluate broad sets of alternatives with mostly qualitative techniques, while conceptual design tools evaluate narrow set of alternatives with multidisciplinary tools. In order for these two fields to communicate effectively, a common platform for both concerns is desired. This research is an original contribution to a three-part solution to this problem. It discusses the …
The Effects Of Temperature And Relative Humidity On Exposure Of Legacy And Future Technology Hardware, Under Real Data Center Conditions In An Ansi/Isa Classified G2 Environment,
2016
University of Texas at Arlington
The Effects Of Temperature And Relative Humidity On Exposure Of Legacy And Future Technology Hardware, Under Real Data Center Conditions In An Ansi/Isa Classified G2 Environment, Oluwaseun Michael Awe
Mechanical and Aerospace Engineering Dissertations - Archive
It is well established that it is safe to operate information technology (IT) equipment in a G1 classified contaminant severity level when operating within specified ASHRAE recommended and allowable limits in an air-side economizer data center. This is basis for which electronic equipment manufacturers provide warranty for their products. IT equipment manufacturers in the US now requires data centers operators to demonstrate that they meet all the specified conditions consistently before fulfilling warranty equipment failure. This places limitation to where data center utilizing air-side economizer can be located. In order to determine the reliability of electronic hardware in higher severity …
Analysis Of Composite Beams With Airfoil Cross-Sections With I-Section Stiffener Under Tension And Bi-Directional Moments,
2016
University of Texas at Arlington
Analysis Of Composite Beams With Airfoil Cross-Sections With I-Section Stiffener Under Tension And Bi-Directional Moments, Peter Louis Leboulluec
Mechanical and Aerospace Engineering Dissertations - Archive
Annual wind power generation capacity in the US has increased from 3 gigawatts in 2000 to 61 gigawatts in 2013 and is on track to fulfill 20% of projected U.S. electricity needs (305 gigawatts) by 2030. To enable the increase in electricity generation of wind turbines, longer blades are being designed which require improved engineered blades to handle higher loads. Thus, the wind turbine industry is turning to the use of carbon-epoxy composite materials to take advantage of their low weight yet high strength ratio and improved fatigue resistance. Current analyses to design turbine blades utilize either Finite Element Analysis …
Thermal Energy Storage For Expanded Use Of Data Center Indirect/Direct Evaporative Cooling,
2016
University of Texas at Arlington
Thermal Energy Storage For Expanded Use Of Data Center Indirect/Direct Evaporative Cooling, Jefferey Luttrell
Mechanical and Aerospace Engineering Dissertations - Archive
Computer cooling system design evolved over time with goals of increasing efficiency and decreasing cost. Early computers were essentially hand-built and very expensive. Reliable operation required aggressive cooling to maintain acceptable component temperatures and this was achieved with relatively low ventilation air temperatures. With time, the scale of operations increased to the point that operating cost began to strongly influence design decisions. Computer room air conditioners consumed substantial amounts of electrical power, in some situations almost as much power as the computer equipment. One cost saving idea used outside air when the ambient temperature fell below the normal cooling supply …
Understanding The Alchemilla Leaf And Its Hydrophobicity,
2016
University of Texas at Arlington
Understanding The Alchemilla Leaf And Its Hydrophobicity, Atul Mohandas Kootathil
Mechanical and Aerospace Engineering Theses - Archive
The Alchemilla leaf has been well known and studied frequently for its hydrophobic ability. However, much difficulty has been met in replicating its microstructure for hydrophobic applications. Also, not much experimental data was found on the behavior of leaf’s microstructure. Gathering information from experimental results may provide new understanding of its wetting properties before attempting to mimetic its wetting behavior. In this research, the focus is to detail the observed solid-water-air interaction on Alchemilla leaf by simulating condensation, evaporation and rainfall conditions, which are the common ways that a plant may interact with water drops in nature. Documenting these observations …
Attitude Stabilization Of Spacecraft Using Moving Masses,
2016
University of Texas at Arlington
Attitude Stabilization Of Spacecraft Using Moving Masses, Juran Hwang
Mechanical and Aerospace Engineering Theses - Archive
This research investigates the ability of stabilizing spacecraft rotational motion by internal mass actuation. The mass actuation mechanism consists of three internal masses placed along the three axes at some offset distance that can move to induce inertial forces and moments and change the inertia matrix and center of mass. A set of nonlinear equations of motion are developed to model the motion, both orbital and rotational dynamics and kinematics, of a spacecraft with mass and inertial variation due to internal mass actuation, under the gravitational field of Earth. The equations inherently include the inertia effect of the mass motion …
Developing And Validating Energy Models For Indirect And Direct Evaporative Cooling Used In Datacenters,
2016
University of Texas at Arlington
Developing And Validating Energy Models For Indirect And Direct Evaporative Cooling Used In Datacenters, Rajesh Kasukurthy
Mechanical and Aerospace Engineering Theses - Archive
In the present day to day life, Internet of things is everything, i.e., we need internet and telecommunication for almost every task of our life and these require data from data centers. These data centers provide various facilities like data processing, storage, and transmission, and maintenance, operations etc., for performing these tasks, a huge amount of power is consumed by the data center, which in turn generates large amount of heat. As these data centers are to be made operational throughout the year, cooling of data centers is of utmost importance. These cooling systems like air conditioners, economizers and evaporative …
Mechanical Property Evaluation Of Magnesium Rich Primer Coating System Over Aa 2024 T-3 Aluminum Alloy By Nano-Inedntation,
2016
University of Texas at Arlington
Mechanical Property Evaluation Of Magnesium Rich Primer Coating System Over Aa 2024 T-3 Aluminum Alloy By Nano-Inedntation, Hongyi Qu
Mechanical and Aerospace Engineering Theses - Archive
Aluminum alloy is widely used as a major structural material, such as for wing and fuselage, in aerospace industry. Corrosion is the most insidious form of damage to aluminum alloy, which can cause aircraft structure damage and related safety issue. Coating is generally used in industry to protect metal structure. An alternative to present toxic chromium primer coating system, magnesium rich primer (MgRP) has been developed to protect AA 2024 T-3. Studies have demonstrated the anti-corrosion performance of MgRP. However, the interlayer material heterogeneity can affect the mechanical properties of coating such as modulus, hardness and interfacial behavior. In the …
Active Torque Vectoring For All Wheel Drive Fsae Electric Car,
2016
University of Texas at Arlington
Active Torque Vectoring For All Wheel Drive Fsae Electric Car, Vikas Tukaram T Pawar
Mechanical and Aerospace Engineering Theses - Archive
UTA Racing is known for building well-engineered FSAE racecars. This year team is building, its first electric car by using AWD in-wheel motor concept car E-16. All wheel drive electric vehicles has an ability to apply instantaneous torque to all four wheels permit increased car performance. An ‘Active Model Based Torque Vectoring System controller’ is designed to realize this objective. The controller was designed to replicate three electronically controlled LSD's on an all-wheel drive platform with different control strategies. This was achieved based on the principal of distributing total driver requested torque between wheels, equivalent to the percentage of the …
Guidance Navigation And Control Implementation For Unmanned Ground Vehicle Using Ni-Myrio,
2016
University of Texas at Arlington
Guidance Navigation And Control Implementation For Unmanned Ground Vehicle Using Ni-Myrio, Ishwarya Srinivasan
Mechanical and Aerospace Engineering Theses - Archive
This research effort aims at investigating alternative real-time implementation software and hardware for Guidance, Navigation and Control (GNC) algorithms for an Unmanned Ground Vehicle (UGV). A GNC algorithm was previously developed for a skid-steered tracked UGV to go through assigned waypoints based on encoder counts. The UGV has two electric motors driving the tracks on each side and two encoders providing the speeds of the drive wheels. This algorithm was implemented using Matlab/Simulink-based model running on a mini computer, interfacing with the electric motors and encoders through a specialty control board. This current effort is to implement the same GNC …
