Buckling And Post Buckling Of Structural Components,
2010
University of Texas at Arlington
Buckling And Post Buckling Of Structural Components, Shruti Deshpande
Mechanical and Aerospace Engineering Theses - Archive
Structural members and components, such as shells and trusses of different geometries, form the intricate and deep seated parts in the manufacturing of missiles submarines, rockets, airplanes, automobiles etc and find applications in civil structures such as bridges. These members are comprised of components like conical frusta, cylindrical panels and shallow trusses. In many cases, the sole purpose of such shell structures is to absorb the energy generated due to impact which means, that these structures are subjected to heavy loads and can experience failure due to buckling. The objective of this work is to study the buckling and post …
Aerodynamic Shape Optimization Of 3d Gas Turbine Blade Using Differerential Evolution Method,
2010
University of Texas at Arlington
Aerodynamic Shape Optimization Of 3d Gas Turbine Blade Using Differerential Evolution Method, Darshak Joshi
Mechanical and Aerospace Engineering Theses - Archive
This paper outlines the aerodynamics shape optimization process of a 3D VKI gas turbine blade using Computational Fluid Dynamics (CFD) and differential evolution optimization method. The main objective of this work is to improve outlet total pressure for better aerodynamic performance. This benefit is achieved by optimizing the stacking line path of the turbine blade in 3D annular cascade for which higher exit total pressure is achieved. The optimization process starts with generating a 3D annular cascade with a boundary domain and meshing it using GAMBIT and is then solved in FLUENT using viscous flow analysis. The original stacking line …
Simulation Of Indeterminate Multi-Point Impact And Contact With Friction,
2010
University of Texas at Arlington
Simulation Of Indeterminate Multi-Point Impact And Contact With Friction, Adrian Rodriguez
Mechanical and Aerospace Engineering Theses - Archive
This work presents a method for determining the post-impact behavior of a rigid-body undergoing simultaneous, multiple impacts with friction. A discrete algebraic model is used with an event-driven function which finds impact events. In this work, the indeterminate nature of the equations of motion encountered at impact are examined. A velocity constraint is developed based on the rigid-body assumption to address the equations and an impact law is used to determine the impulsive forces. The slip-state of each contact point is then determined and appropriate methods are used to resolve the post-impact velocities. Friction is treated as a complementarity problem …
Reanalysis For Static And Steady State Structure Response,
2010
University of Texas at Arlington
Reanalysis For Static And Steady State Structure Response, Kunal Rohit Parikh
Mechanical and Aerospace Engineering Theses - Archive
Reanalysis of a structure has become very important in structural analysis, as it reduces the cost and the computational time required to measure the response of the structure after it has been modified. As the importance of reanalysis has become clear, more and more research has been carried out in the field of reanalysis, which has lead to many different methods to carry out reanalysis. There are various methods which can be used for any single structural reanalysis problem and it would give us different results depending upon the method selected. Due to lot of methods which are available to …
Richtmyer-Meshkov Instability In Reactive Mixtures.,
2010
University of Texas at Arlington
Richtmyer-Meshkov Instability In Reactive Mixtures., Madhuri Ungarala
Mechanical and Aerospace Engineering Theses - Archive
This research analyzes the effect of reactivity on the Richtmyer-Meshkov instability with particular emphasis on the velocity and wave number scaling and on the effect of free detonation instability modes on the interface corrugation rate. This analysis is performed by solving numerically for the first order perturbation generated by the shock-induced acceleration of an initially corrugated interface. The objective of this research is to analyze the effect of mixture reactivity on the process supported by a shock sweeping across a corrugated interface from high density to low density fluid. This scenario is antithetical to the classical Richtmyer analysis where transmitted …
Analysis Of Thrust Development In A Pulse Detonaton Engine,
2010
University of Texas at Arlington
Analysis Of Thrust Development In A Pulse Detonaton Engine, Kishore Nekkanti
Mechanical and Aerospace Engineering Theses - Archive
Pulse detonation engines (PDE) employ detonation waves to compress and burn the fuel and oxidizer mixture which results in the release of high pressure and temperature. The objective of the present study is to analytically model the PDE cycle and to study the pressure, temperature, velocity and density distributions during the Taylor rarefaction wave, reflected rarefaction wave and the blow down process. A two-dimensional supersonic nozzle is designed analytically by using the method of characteristics. The average values of nozzle thrust for one PDE cycle are calculated analytically using the impulse function and thrust coefficient. The variation of PDE thrust …
Multiscale Modeling Of Targeted Drug Delivery And Diep Flap Perfusion,
2010
University of Texas at Arlington
Multiscale Modeling Of Targeted Drug Delivery And Diep Flap Perfusion, Manohara Mariyappa
Mechanical and Aerospace Engineering Theses - Archive
Advances in computational techniques have changed diagnosis and treatment of chronic diseases. This thesis work is composed of developing computational models in two application areas: nanomedicine and determining DIEP flap perfusion for reconstructive surgery. Nanomedicine poses a new frontier in medical technology with the advantages of targeted delivery and patient specific medicine. Current advances in nanomedicine are aiding the discovery and rationale design of many new classes of nanoparticles as drug delivery vectors for cancer treatment and image enhancing. An important advantage of targeted drug delivery is reduced drug dosage that enables the minimization of adverse effects associated with elevated …
Thermal Management Of Outside Plant Telecommunication Cabinets: Design And Cfd Modeling Methodology,
2010
University of Texas at Arlington
Thermal Management Of Outside Plant Telecommunication Cabinets: Design And Cfd Modeling Methodology, Feroz Ahamed Iqbal Mariam
Mechanical and Aerospace Engineering Theses - Archive
Over the years there has been a steady increase in the number of transistors being packed into the same footprint of a die, which has led to an increase in the power densities of electronics. The thermal management of electronic equipment therefore is becoming an integral part of packaging design. Access networks provide the last mile of connectivity for the telecommunication network users. In the access network, the outside plant telecommunication cabinets houses electronic components and switching devices. These cabinets are standalone outdoor cabinets and many a times they are located in hostile environments. Therefore, it is necessary that these …
A Low Cost Micro Scale Cyclone Seperator- Design And Computational Fluid Dynamics Analysis,
2010
University of Texas at Arlington
A Low Cost Micro Scale Cyclone Seperator- Design And Computational Fluid Dynamics Analysis, Deval Pandya
Mechanical and Aerospace Engineering Theses - Archive
Microparticle separation process has a variety of application varying from application in biological and biomedical industries for analysis and diagnosis, in biogas manufacturing to separate phases as well as in defense sector for detection of biological weapons like anthrax. Available electrical, magnetic, acoustic and various other methods are either very costly or not portable. The proposed design of micro scale cyclone separator is low cost as well as portable and easy to manufacture. Huge cyclone separators are widely used in various industries since decades but due to lack of research in micro scale cyclones no direct and sufficient data is …
Effect Of Friction On The Zel'dovich Von Neumann Doring To Chapman Jouguet Transition,
2010
University of Texas at Arlington
Effect Of Friction On The Zel'dovich Von Neumann Doring To Chapman Jouguet Transition, Sushma Rao
Mechanical and Aerospace Engineering Theses - Archive
Detonation theory proposes Chapman-Jouguet state of equilibrium due to the sonic speed of the products relative to the wave. Experimental observations however indicated the existence of a sub-Chapman-Jouguet state. The dissertation proposes that friction plays a role in defining such a sub-optimal state in detonation wave propagation in ducts. The problem is addressed analytically by decoupling the friction losses from the chemical reactions. The non-equilibrium conditions associated with detonation is modeled by detailed chemistry.
Multi Objective Thermal And Energy Based Design Optimization Of Telecommunication Cabinets/Shelters,
2010
University of Texas at Arlington
Multi Objective Thermal And Energy Based Design Optimization Of Telecommunication Cabinets/Shelters, Bharathkrishnan Muralidharan
Mechanical and Aerospace Engineering Theses - Archive
The miniaturization and convergence of the consumer electronic products such as cell phones and digital cameras has necessitated an increase in the number of transistors on a die, board and systems. This has resulted in a requirement for a more robust thermal management of such electronics to increase the reliability of the system. Access networks provide the last mile of connectivity for the telecommunication network users. In the access network, the outside plant telecommunication cabinets houses electronic components and switching devices. These cabinets are standalone outdoor enclosures, and many a times they are located in hostile environments. With the current …
Experimental Study Of Micro-Vortex Generators At Mach 2.5,
2010
University of Texas at Arlington
Experimental Study Of Micro-Vortex Generators At Mach 2.5, Adam J. Pierce
Mechanical and Aerospace Engineering Theses - Archive
Vortex generators are geometrical shapes that produce trailing vortices and are widely used for their ability to improve the flow quality over areas where flow separation may occur. Current topics involve utilizing the performance capabilities of vortex generators to influence the boundary layer under supersonic conditions. Such influence may provide an alternative means of reducing boundary layer flow separation and improving the overall quality of the flow in the boundary layer. This influence would maintain low drag in supersonic inlets and reduce the need for mechanical equipment used for boundary layer bleed leading to a reduction in aircraft weight and …
Experimental Investigation Of Thermal Behaviour Of Air Foil Bearings,
2010
University of Texas at Arlington
Experimental Investigation Of Thermal Behaviour Of Air Foil Bearings, Ramesh Pandeshwara Sadashiva
Mechanical and Aerospace Engineering Theses - Archive
Micro-turbo machinery demands gas bearings to ensure compactness, lightweight and extreme temperature operation. Gas bearings with large stiffness and damping, and preferably of low cost, will enable successful commercial applications. One of the gas bearing which is used for experimental investigation is the Air foil bearing. Previously developed test rig has been modified and further developed for investigating this bearing at various temperatures and speeds. These gas bearings are self acting hydrodynamic air bearings which have been successfully applied to a variety of turbo machinery applications. This new modified test rig also has the capability to measure bearing torque during …
Analysis And Design Of A Two-Wheeled Robot With Multiple User Interface Inputs And Vision Feedback Control,
2010
University of Texas at Arlington
Analysis And Design Of A Two-Wheeled Robot With Multiple User Interface Inputs And Vision Feedback Control, Eric Stephen Olson
Mechanical and Aerospace Engineering Theses - Archive
This thesis describes the development of a small, inexpensive, controllable mobile two-wheeled robot. It also describes the development of a software interface which allows several open- and closed-loop control methods to be easily implemented. The developed hardware and software modules provide for an open and modular system for research purposes. This is demonstrated through the Bluetooth wireless control of the robot using LabVIEW based software modules. The open-loop control inputs implemented are sliders in a LabVIEW GUI, joystick, and voice commands. The closed-loop control methods included a PD control algorithm that guides the robot to go directly to a user …
Applications Of Sensitivity Data To Eigensolution Reanalysis Of Modified Structures,
2010
University of Texas at Arlington
Applications Of Sensitivity Data To Eigensolution Reanalysis Of Modified Structures, Chandrashekhar Sureshchandra Patadia
Mechanical and Aerospace Engineering Theses - Archive
Methods of computing eigensolution sensitivity have been known for a long time. Both exact and approximate methods are available in the literature. While eigenvalue sensitivity is used routinely in structural optimization with eigenvalue constraints, few application of eigenvector derivatives are reported in the literature. The objective of this thesis is to present an effective eigensolution reanalysis approach using first and second order eigenvector sensitivity data. In the proposed new approach, modes shapes and their derivatives are used as basis vector for eigensolution of the modified system. Comparison of numerical results with several existing eigensolution reanalysis methods shows the proposed algorithms …
Inverse Design Of Airfoils Using A Flexible Membrane Method,
2010
University of Texas at Arlington
Inverse Design Of Airfoils Using A Flexible Membrane Method, Kamon Thinsurat
Mechanical and Aerospace Engineering Theses - Archive
The Modified Garabedian Mc-Fadden (MGM) method is used to inversely design airfoils. The Finite Difference Method (FDM) for Non-Uniform Grids was developed to discretize the MGM equation for numerical solving. The Finite Difference Method (FDM) for Non-Uniform Grids has the advantage of being used flexibly with an unstructured grids airfoil. The commercial software FLUENT is being used as the flow solver. Several conditions are set in FLUENT such as subsonic inviscid flow, subsonic viscous flow, transonic inviscid flow, and transonic viscous flow to test the inverse design code for each condition. A moving grid program is used to create a …
Effective Thermal Management Of Electronic Devices From System To Die Level,
2010
University of Texas at Arlington
Effective Thermal Management Of Electronic Devices From System To Die Level, Saket Karajgikar
Mechanical and Aerospace Engineering Dissertations - Archive
In any electronic device, the resistance to the flow of current through the transistors, interconnects, etc. results in a significant heat generation. If this heat is not removed from the device by providing appropriate cooling solutions, the possibility of thermal run away is very high. Under this condition the temperature would continue to rise until it reaches a point at which the device ceases to operate or loses its physical integrity. In presence of a cooling mechanism, the temperature rise is moderated as it asymptotically reaches an acceptable steady state value. Before any device is introduced in the market, it …
Trajectory Uncertainty Analysis For The Development Of A Queuing Model For The National Airspace System,
2010
University of Texas at Arlington
Trajectory Uncertainty Analysis For The Development Of A Queuing Model For The National Airspace System, Manju Nag
Mechanical and Aerospace Engineering Theses - Archive
In this research, we propose to support the development of a queuing model for the National Airspace System (NAS) by providing distributions for the various phases of flight, accounting for the uncertainties in flight trajectory which includes factors such as weight, power factor, lift co-efficient. In addition to this, a detailed study is done on the impact of weather on flight routes and two days in 2006 are compared to show the effect of weather on flight times. The research develops from a good understanding of the NAS and its requirements to implement a system capable of dealing with issues …
Aerodynamic Shape Optimization Of A Vertical Axis Wind Turbine,
2010
University of Texas at Arlington
Aerodynamic Shape Optimization Of A Vertical Axis Wind Turbine, Travis Justin Carrigan
Mechanical and Aerospace Engineering Theses - Archive
The purpose of this study is to introduce and demonstrate a fully automated process for optimizing the airfoil cross-section of a vertical axis wind turbine (VAWT). The objective is to maximize the torque while enforcing typical wind turbine design constraints such as tip speed ratio, solidity, and blade profile. By fixing the tip speed ratio and solidity of the wind turbine, there exists an airfoil cross-section for which the torque can be maximized, requiring the development of an iterative design system.The design system required to maximize torque incorporates rapid geometry generation and automated hybrid mesh generation tools with viscous, unsteady …
Effect Of Structural Design Parameters On Wafer Level Csp Ball Shear Strength And Their Influence On Accelerated Thermal Cycling Reliability,
2010
University of Texas at Arlington
Effect Of Structural Design Parameters On Wafer Level Csp Ball Shear Strength And Their Influence On Accelerated Thermal Cycling Reliability, Nikhil R. Lakhkar
Mechanical and Aerospace Engineering Dissertations - Archive
Wafer level chip scale package (WLCSP) is one of the most popular packages due to its size and cost advantages. It is expected that the usage of WLCSP in microelectronics and MEMS industry combined is going to cross 16000 Million Units by 2013. One of the main advantages of implementing WLCSP is its time to market because most of the package is done at the wafer level. Once the wafer processing is completed the package is just diced and mounted on board and the board is ready to go. However, just like any other package WLCSP too is not ideal …
