Stress Analysis In Curved Composite Due To Thermal Loading,
2012
University of Texas at Arlington
Stress Analysis In Curved Composite Due To Thermal Loading, Jared Cornelius Polk
Mechanical and Aerospace Engineering Theses - Archive
Many structures in aircraft, cars, trucks, ships, machines, tools, bridges, and buildings, consist of curved sections. These sections vary from straight line segments that have curvature at either one or both ends, segments with compound curvatures, segments with two mutually perpendicular curvatures or Gaussian curvatures, and segments with a simple curvature. With the advancements made in multi-purpose composites over the past 60 years, composites slowly but steadily have been appearing in these various vehicles, compound structures, and buildings. These composite sections provide added benefits over isotropic, polymeric, and ceramic materials by generally having a higher specific strength, higher specific stiffnesses, …
Using Gpu-Based Computing To Accelerate Finite Element Problems,
2012
University of Texas at Arlington
Using Gpu-Based Computing To Accelerate Finite Element Problems, Jacob Watt
Mechanical and Aerospace Engineering Theses - Archive
Historically Graphics Processing Units (GPU) have been used for offloading graphical visualization and made popular in use for video games, but with the development of NVIDIA's CUDA architecture and programing language there has been an increase in the use of GPUs in general purpose (GPGPU) programing. Problems involving large systems of linear equations, such as the Finite Element Analysis (FEA), can benefit greatly from the parallel computing capabilities of GPUs. In my thesis I will solve Poisson's equation and discuss the advantages and disadvantages of the massively parallel environment of GPUs. I will show that on a unstructured grid that …
Determination Of Factors To Improve Effectiveness Of Triangulation Members For A Formula Sae Race Car Frame,
2012
University of Texas at Arlington
Determination Of Factors To Improve Effectiveness Of Triangulation Members For A Formula Sae Race Car Frame, Vikram Nair
Mechanical and Aerospace Engineering Theses - Archive
This thesis suggests which factors have significant effect on the torsional and flexural stiffness of a space frame without contributing excessively to its weight. These factors are used as design variables to display the interaction plots generated by performing a Design of Experiments (DOE) using the Hyperstudy tool in Hyperworks by Altair®. The DOE will also provide a mathematical model which can help predict the responses by varying several factors in the design. The node - element models are created in ANSYS classic and are analyzed for various load cases that are representative of the loads on a formula SAE …
Characterization Of Uta Hypersonic Shock Tunnel,
2012
University of Texas at Arlington
Characterization Of Uta Hypersonic Shock Tunnel, Derek Glenn Leamon
Mechanical and Aerospace Engineering Theses - Archive
Characterization of a hypersonic shock tunnel was performed under low enthalpy conditions. A rake was designed and fabricated to measure pitot pressure and heat flux at three axial locations in the test section. Pitot pressures at three locations provided an indication of the inviscid core. Thin film RTD sensors with a fast response time were fabricated to measure the heat flux under these low enthalpy conditions. The Cook-Felderman algorithm was used to estimate the heat flux from the temperature history. Results for the first millisecond of test time showed a probe tip surface temperature increase of 15-20 K and a …
Computational Study Of Heat Transfer Enhancement For A Dimpled Surface In A Channel,
2012
University of Texas at Arlington
Computational Study Of Heat Transfer Enhancement For A Dimpled Surface In A Channel, Abhijit Paranjape
Mechanical and Aerospace Engineering Theses - Archive
Heat transfer augmentation techniques have gained great importance in different engineering applications to deal with thermal management issues. In this work, a numerical investigation was carried out to see the effects of spherical dimple arrays on heat transfer characteristics in a channel. These effects were observed for dimples on the bottom wall of the channel for laminar airflows. The effects of a 21×7 staggered array and a 19×4 inline array on the bottom wall were investigated using a 3D steady viscous computational fluid dynamics package with an unstructured grid. The heat transfer characteristics were studied as a function of the …
Spur Gear Analysis Using Mathcad,
2012
University of Texas at Arlington
Spur Gear Analysis Using Mathcad, Jaydeep K. Panchal
Mechanical and Aerospace Engineering Theses - Archive
In gear manufacturing applications, it is required to calculate surface stress and bending stress with minimum error. This thesis represents engineering calculation of bending and surface compression of external teethed involute spur gear. One may change the input values to calculate the engineering data for gears. The freedom of changing input values gives the capability to program to calculate for factor, Y; and the bending geometry factor, J to analyze spur gear geometry. Here the engineering gear calculation has been done by developing program in Mathcad software. The program is designed to calculate surface and bending stress data by input …
Torsional Analysis Of A Composite I-Beam,
2012
University of Texas at Arlington
Torsional Analysis Of A Composite I-Beam, Vishal Mukesh Smita Sanghavi
Mechanical and Aerospace Engineering Theses - Archive
A simple methodology for analysis of thin walled composite I-Beam subjected to free torsion and restrained torsion is developed. Classical Lamination Theory is extended from the laminate level to the structural level for analysis purpose.The developed expressions for shear center, equivalent torsional rigidity and equivalent warping rigidity for a composite mono-symmetric I-Beam depends on the material properties, ply stacking sequence, fiber orientation and geometryThe results from the proposed theory gives better agreement with the ANSYSTM results than the traditional smeared property approach.
Control Of A Teleoperating Robotic Arm Subject To Time Delays,
2012
University of Texas at Arlington
Control Of A Teleoperating Robotic Arm Subject To Time Delays, Pankaj Prakash Sarda
Mechanical and Aerospace Engineering Theses - Archive
Robotics in Minimally Invasive Surgeries (MIS) can be explored to its full potential if there is complete transparency between the surgeon and the virtual environment. In the setup, haptic device which conveys force from the surgeon to the surgery site and vice verse acts as the master station and robotic arm at the surgery site acts as the slave robot. In surgeries carried out remotely, time delays in the communication channels can cause commanded velocity/force to overshoot before the surgeon can even pull out during a task causing temporary or permanent damage during the surgery. Since the physical capability of …
Study Of The Surface Roughness Evolution In Fatigued 316l Stainless Steel,
2012
University of Texas at Arlington
Study Of The Surface Roughness Evolution In Fatigued 316l Stainless Steel, Ye Wang
Mechanical and Aerospace Engineering Theses - Archive
Fatigue is a critical design consideration in many aerospace structures. As improvements are sought in overall performance, maintenance requirements, and total service life of modern aircrafts, the demands for fatigue control techniques, such as material design for fatigue resistance, reliable fatigue life prediction, and continuous material damage monitoring, have increased. The most common practices to ensure fatigue safety include: fracture mechanics based fatigue life prediction, periodic non-destructive inspections, and material processing control. Reasonable successes have been achieved by applying these three techniques to ensure the safe operation of aerospace structures. It is worth mentioning that most of the present fatigue …
New Developments In Cognitive Optimization,
2012
University of Texas at Arlington
New Developments In Cognitive Optimization, Parvati Aruna Kandala
Mechanical and Aerospace Engineering Theses - Archive
This work presents an approach to solve function optimization problems using cognitive optimization. A cognitive search algorithm which is developed mimics human cognition in structure and characteristics. This algorithm is developed based on the key aspects of a cognitive system, namely, the use of prior knowledge, communication, and self-organization. The processes have the knowledge of how to solve the optimization problems from traditional techniques such as bracketing, gradient search and interval-halving methods. This search algorithm shows that, by passing messages, the processes communicate, share information, and self-organize around the solution. A mat lab program is coded to perform the tests …
Transient Analysis Of A Pulsed Detonation Combustor Using The Numerical Propulsion System Simulation,
2012
University of Texas at Arlington
Transient Analysis Of A Pulsed Detonation Combustor Using The Numerical Propulsion System Simulation, Anthony Scott Hasler
Mechanical and Aerospace Engineering Theses - Archive
The performance of a hybrid mixed flow turbofan (with detonation tubes installed in the bypass duct) is investigated in this study and compared with a baseline model of a mixed flow turbofan with a standard combustion chamber as a duct burner. Previous studies have shown that pulsed detonation combustors have the potential to be more efficient than standard combustors, but they also present new challenges that must be overcome before they can be utilized. The Numerical Propulsion System Simulation (NPSS) will be used to perform the analysis with a pulsed detonation combustor model based on a numerical simulation done by …
Analytical Method For Analyzing C-Channel Stiffener Made Of Laminate Composite,
2012
University of Texas at Arlington
Analytical Method For Analyzing C-Channel Stiffener Made Of Laminate Composite, Tattchapong Kumton
Mechanical and Aerospace Engineering Theses - Archive
Composite materials play the important role in the aviation industry. Conventional materials such as aluminum were replaced by composite material on the main structures. The objective of this study focuses on development of analytical method to analyze the laminated composite structure with C-channel cross-section. A lamination theory base closed-form solution was developed to analysis ply stresses on the C-channel cross-section. The developed method contains the effects of coupling due to unsymmetrical of both laminate and structural configuration levels. The present method also included the expression of the sectional properties such as centroid, axial and bending stiffnesses of cross-section. The results …
Particle Advection Using The Lattice-Boltzmann Method,
2012
University of Texas at Arlington
Particle Advection Using The Lattice-Boltzmann Method, Matthew Carroll
Mechanical and Aerospace Engineering Theses - Archive
Lattice-Boltzmann Method (LBM) CFD analysis can be helpful in analysing fluid flow through porous media and complex geometries that may be difficult to simulate using traditional CFD methods. In this thesis, the technical details of lattice Botlzmann particle advection are presented. The lattice Botlzmann equations are explained as well as a method for introducing a particle in a fluid flow and advecting the particle using viscous, pressure, and gravitational forces. A method is developed to advect a particle through a computational lattice mesh using pressure forces, gravitational forces, as well as LBM-specific viscous force equations. The capability of the particle …
Stress Concentrations Around A Square Cutout In A Composite Plate,
2012
University of Texas at Arlington
Stress Concentrations Around A Square Cutout In A Composite Plate, Colin Cannon
Mechanical and Aerospace Engineering Theses - Archive
Composite structure in the aircraft industry has been in development for well over half a century and yet the understanding of the effects of a square cutout is generally limited to quasi-isotropic laminates. Currently, the closed-form solution to calculate the stresses around a cutout is limited to symmetric anisotropic laminates with limitations on the cutout shapes. Finite Element Analysis, using MSC PATRAN and NASTRAN, was performed on 2D composite laminates containing square cutouts with rounded corners. The laminate stacking sequence was varied from symmetrical and balanced to unsymmetrical and unbalanced and the square cutouts each had different radii at the …
Cfd Based Aerodynamic Modeling To Study Flight Dynamics Of A Flapping Wing Micro Air Vehicle,
2012
University of Texas at Arlington
Cfd Based Aerodynamic Modeling To Study Flight Dynamics Of A Flapping Wing Micro Air Vehicle, Alok Ashok Rege
Mechanical and Aerospace Engineering Theses - Archive
The demand for small unmanned air vehicles, commonly termed micro air vehicles or MAV's, is rapidly increasing. Driven by applications ranging from civil search-and-rescue missions to military surveillance missions, there is a rising level of interest and investment in better vehicle designs, and miniaturized components are enabling many rapid advances. The need to better understand fundamental aspects of flight for small vehicles has spawned a surge in high quality research in the area of micro air vehicles. These aircraft have a set of constraints which are, in many ways, considerably different from that of traditional aircraft and are often best …
Impact Of Louver Orientation On Air Flow Distribution And Thermal Management Of Data Centers,
2012
University of Texas at Arlington
Impact Of Louver Orientation On Air Flow Distribution And Thermal Management Of Data Centers, Kushal A. Aurangabadkar
Mechanical and Aerospace Engineering Theses - Archive
Nowadays with the increasing use of technology, Traditional data centers are being replaced by the highly efficient Containerized or Modular Data centers. The cooling systems and constructional cost employed for Traditional Data centers is more and inefficient. The research intricate, about 23% of the power is consumed by HVAC cooling units and which in turn leads to increase in operational costs. Hence in order to reduce the operational costs, free cooling with Air side economizer is incorporated, compared to other cooling systems. Airflow Distribution plays an important role in the Thermal management, if the airflow is less in quantity it …
Assessment Of The Mechanical Integrity Of Cu/Low-K Dielectric In A Flip Chip Package,
2012
University of Texas at Arlington
Assessment Of The Mechanical Integrity Of Cu/Low-K Dielectric In A Flip Chip Package, Thiagarajan Raman
Mechanical and Aerospace Engineering Theses - Archive
Miniaturization and more recently convergence have been driving the industry since the invention of the transistor and integrated circuit (IC). Though the gate delay has decreased with transistor scaling, the increase in the resistive capacitive (RC) interconnect delay due to shrinking interconnect dimensions has become a serious concern for the development of future-generation electronics. To reduce the delay due to resistance R, a major technology change was the replacement of Aluminum (Al) with Copper (Cu) interconnect layers in the BEoL (Back-end-of-line). Recently, some investigators have suggested using low-k dielectric (having dielectric constant less than 4) instead of SiO2 (k= 3.9) …
Numerical Study Of Sidewall Filling For Gas-Fed Pulse Detonation Engines,
2012
University of Texas at Arlington
Numerical Study Of Sidewall Filling For Gas-Fed Pulse Detonation Engines, Wunnarat Rongrat
Mechanical and Aerospace Engineering Theses - Archive
Pulse detonation engines for aerospace propulsion are required to operate at 50-100 Hz meaning that each pulse is 10-20 ms long. Filling of the engine and the related purging process become dominant due to their long duration compared to ignition and detonation wave propagation. This study uses ANSYS FLUENT to investigate the filling of a 1 m long tube with an internal diameter of 100 mm. Six different configurations were investigated with an endwall port and various sidewall arrangements, including stagger and inclination. A stoichiometric mixture of gaseous octane and air at STP was used to ll the tube at …
Thermal Analysis Of High End Servers Based On Development Of Detail Model And Experiments,
2012
University of Texas at Arlington
Thermal Analysis Of High End Servers Based On Development Of Detail Model And Experiments, Shreyas Sampath
Mechanical and Aerospace Engineering Theses - Archive
Thermal management of an efficient data center can be primarily dictated by efficient servers. Continued increase in power density and power dissipation of high end processors, thermal analysis and management has made it strategically important in the challenge of advanced thermal solutions. Present day CFD software provides powerful tools to create very accurate fluid and heat transfer solutions. Validation of a detailed model of a server in CFD corresponds to accurate flow and temperature models and these detailed server models are the foundational blocks for accurate data center thermal management solutions. In this research, an experimental study of the thermal …
New Detonation Concepts For Propulsion And Power Generation,
2012
University of Texas at Arlington
New Detonation Concepts For Propulsion And Power Generation, Eric Braun
Mechanical and Aerospace Engineering Dissertations - Archive
A series of related analytical and experimental studies are focused on utilizing detonations for emerging propulsion and power generation devices. An understanding of the physical and thermodynamic processes for this unsteady thermodynamic cycle has taken over 100 years to develop. An overview of the thermodynamic processes and development history is provided.Thermodynamic cycle analysis of detonation-based systems has often been studied using surrogate models. A real gas model is used for a thermal efficiency prediction of a detonation wave based on the work and heat specified by process path diagrams and a control volume analysis. A combined first and second law …
