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Rapid Prediction Of Low-Boom And Aerodynamic Performance Of Supersonic Transport Aircraft Using Panel Methods, Ted N. Giblette Dec 2019

Rapid Prediction Of Low-Boom And Aerodynamic Performance Of Supersonic Transport Aircraft Using Panel Methods, Ted N. Giblette

All Graduate Theses and Dissertations

The Utah State University Aerolab developed and tested a set of tools for rapid prediction of the loudness of a sonic boom generated by supersonic transport aircraft. This work supported a larger effort led by Texas A&M to investigate the use of adaptive aerostructures in lowering sonic boom loudness at off design conditions. Successful completion of this effort will improve the feasibility of supersonic commercial transport over land.

Funding was provided by a NASA University Leadership Initiative grant to several universities, including Utah State University, as well as industry partners to complete this work over a five year period ...


Calibration Of Hot-Film X-Probes For High Accuracy Angle Alignment In Wind Tunnels, Dallin L. Jackson Aug 2019

Calibration Of Hot-Film X-Probes For High Accuracy Angle Alignment In Wind Tunnels, Dallin L. Jackson

All Graduate Theses and Dissertations

This thesis investigates the use of hot-film thermal anemometers to align a plate on a wind tunnel at Hill Air Force Base that is used to calibrate Angle of Attack Transmitters on F-16s. A reoccuring problem with this wind tunnel is that no two instruments can verify an angle reading of the the mounting plate for the Angle of Attack Transmitters to the air stream in the wind tunnel. Multiple thermal anemometer calibration methods, such as Jorgensen’s equation and a look-up table are implemented to attemp to achieve consistent measurements between multiple probes. The results show that it is ...


Isentropic Efficiency And Theoretical Analysis Of The Planetary Rotor Expander, Joseph L. James Aug 2019

Isentropic Efficiency And Theoretical Analysis Of The Planetary Rotor Expander, Joseph L. James

All Graduate Theses and Dissertations

Expanders allow pressurized fluids to undergo a pressure decrease in a controlled environment via volumetric growth to extract fluid energy. There are many types of expanders, and the objective of this thesis is to model the efficiencies of the planetary rotor expander (PRE), a century-old design undeveloped due to insufficient manufacturing capabilities (until recently). Geometric relationships are derived and mathematical models are generated to determine the efficiency of the PRE as a function of design variables. Two industrially relevant case studies show that, to maximize isentropic efficiency, the planetary rotor expander (PRE) rotational frequency is maximized and rotor geometry optimized.


Study Of The 3w Measurement Of The In-Plane And The Cross-Plane Thermal Properties On Anisotropic Thin Film Materials, Daxi Zhang Dec 2018

Study Of The 3w Measurement Of The In-Plane And The Cross-Plane Thermal Properties On Anisotropic Thin Film Materials, Daxi Zhang

All Graduate Theses and Dissertations

Due to the size of the nano-scale and micro-scale materials, traditional method for measuring the thermal properties of the bulk materials cannot be applied. The 3 OmegaMethod was developed by D. G. Cahill in the early 90s. It was used extensively to measure the thermal properties of thin film dielectric materials. Compare with other simulations or experimental methods, the 3 Omega Method has many advantages. Previous research has indicate that the 3 Omega method is capable of measuring the cross-plane thermal conductivity of thin film materials. In extension, an alternative improvement for measurement of the in-plane thermal conductivity and calculating ...


Development Of An Improved Low-Order Model For Propeller-Wing Interactions, Joshua Taylor Goates Dec 2018

Development Of An Improved Low-Order Model For Propeller-Wing Interactions, Joshua Taylor Goates

All Graduate Theses and Dissertations

For aircraft that have propellers mounted in front of the wings or tail, the prop wash produced by the propellers can have a strong influence on the aerodynamics of the aircraft. As the accelerated air from the propeller flows over the wings and tail, it can cause an alteration in the aerodynamic forces produced by those surfaces. Thus, an understanding of propeller-wing interactions is essential for the design and analysis of many aircraft.

There are multiple existing methods for analyzing the propeller-wing interactions. High order methods, such as wind tunnel testing or computational fluid dynamics, provide very accurate results but ...


Droplet Impact Onto Super-Hydrophobic Surfaces And Determining The Response To Heat And Light Of Terrestrial Cyanobacteria, Benjamin B. Lovett Dec 2018

Droplet Impact Onto Super-Hydrophobic Surfaces And Determining The Response To Heat And Light Of Terrestrial Cyanobacteria, Benjamin B. Lovett

All Graduate Theses and Dissertations

This thesis examines droplets striking water repelling surfaces as well as the movement of a soil based bacteria under various light and heat conditions. Droplet impact studies have shown that introducing a macroscopic feature to a water repelling surface can reduce the amount of time that droplet is in contact with the surface. By manipulating water droplets to impact different sized needles at varying speeds, we present how a needle can induce a similar reduction in the residence time of the droplet to more widely studied features. Results show the spreading and lift-off characteristics of the droplet are dependent on ...


Ultraviolet Diffraction Assisted Image Correlation (Uv-Daic) For Single-Camera 3d Strain Measurement At Extreme Temperatures, Ethan K. Nickerson Aug 2018

Ultraviolet Diffraction Assisted Image Correlation (Uv-Daic) For Single-Camera 3d Strain Measurement At Extreme Temperatures, Ethan K. Nickerson

All Graduate Theses and Dissertations

Digital Image Correlation (DIC) is a technique which uses images taken before and after deformation to determine displacement and strain data over the surface of the sample. In order to obtain this data for both in-plane as well as out-of-plane direction, multiple views of the sample are required. Typically, this is accomplished using multiple cameras, but it is possible to use diffraction gratings to bend the light coming from the specimen in order to allow a single camera to capture multiple views. This technique is referred to as Diffraction Assisted Image Correlation (DAIC) and has been previously demonstrated at room ...


Water Entry Cavity Dynamics, Nathan B. Speirs Aug 2018

Water Entry Cavity Dynamics, Nathan B. Speirs

All Graduate Theses and Dissertations

When a sphere or a stream of water hits the surface of a pool of water and enters a crater or air cavity often forms. This topic has been studied, both formally and informally, for a long time. This dissertation investigates four areas of water impact that are still poorly understood using high-speed photography. First, it examines a stream of droplets impacting on a pool of water, similar to a faucet drizzling into a full bucket. For these types of impacts we predict the depth, diameter, velocity, and shape of the cavities that the droplet stream forms. Second, it examines ...


The Effects Of Geometric And Stoichometric Change In Nanoparticles And Materials On Lattice Thermal Conductivity, W. Tanner Yorgason Aug 2018

The Effects Of Geometric And Stoichometric Change In Nanoparticles And Materials On Lattice Thermal Conductivity, W. Tanner Yorgason

All Graduate Theses and Dissertations

Thermal transport properties are critical for applications ranging from thermal management to energy conversion. Passive thermal management has been an area of study for over a century and has only grown as technology has advanced because it requires no additional energy to remove heat. Changing the nanostructure of the materials involved in passive heat transfer methods, either by geometric changes or stoichiometric changes, can greatly improve the effectiveness of this heat transfer method. In order to explore this further, this work employs LAMMPS molecular dynamics (MD) simulation software to calculate the lattice thermal conductivity (λp) of a nanoparticle (NP ...


Uncertainty Quantification And Sensitivity Analysis Of Multiphysics Environments For Application In Pressurized Water Reactor Design, Cole David Blakely Aug 2018

Uncertainty Quantification And Sensitivity Analysis Of Multiphysics Environments For Application In Pressurized Water Reactor Design, Cole David Blakely

All Graduate Theses and Dissertations

The most common design among U.S. nuclear power plants is the pressurized water reactor (PWR). The three primary design disciplines of these plants are system analysis (which includes thermal hydraulics), neutronics, and fuel performance. The nuclear industry has developed a variety of codes over the course of forty years, each with an emphasis within a specific discipline. Perhaps the greatest difficulty in mathematically modeling a nuclear reactor, is choosing which specific phenomena need to be modeled, and to what detail.

A multiphysics computational environment provides a means of advancing simulations of nuclear plants. Put simply, users are able to ...


Methods For The Aerostructural Design And Optimization Of Wings With Arbitrary Planform And Payload Distribution, Jeffrey D. Taylor May 2018

Methods For The Aerostructural Design And Optimization Of Wings With Arbitrary Planform And Payload Distribution, Jeffrey D. Taylor

All Graduate Theses and Dissertations

The design of an aircraft wing often involves the use of mathematical methods for simultaneous aerodynamic and structural design. The goal of many of these methods is to minimize the drag on the wing. A variety of computer models exist for this purpose, but some require the use of expensive time and computational resources to give meaningful results. As an alternative, some mathematical methods have been developed that give reason ably accurate results without the need for a computer. However, most of these methods can only be used for wings with specific shapes and payload distributions. In this thesis, a ...


Importance Of Exposure Time On Digital Image Correlation (Dic) At Extreme Temperatures, Thinh Quang Thai May 2018

Importance Of Exposure Time On Digital Image Correlation (Dic) At Extreme Temperatures, Thinh Quang Thai

All Graduate Theses and Dissertations

Extreme temperatures have increasingly played an important role in engineering applications, including leading edges during hypersonic flight, spacecraft re-entry, and propulsion systems. In order to design for such thermo-mechanical conditions, materials must be characterized using suitable measurement methods. DIC is a popular and versatile method in full-field measurement. In brief, DIC compares images of a sample between its undeformed and deformed state in order to get displacement and strain field maps. Since the images are acquired from digital cameras, it is important to have high contrast images for meaningful correlation. Exposure time is a pivotal camera setting relating to camera ...


A Propeller Model Based On A Modern Numerical Lifting-Line Algorithm With An Iterativesemi-Free Wake Solver, Zachary S. Montgomery May 2018

A Propeller Model Based On A Modern Numerical Lifting-Line Algorithm With An Iterativesemi-Free Wake Solver, Zachary S. Montgomery

All Graduate Theses and Dissertations

A fundamental aerodynamic analysis technique for a single straight fixed wing has been expounded upon and turned into a modern technique that can analyze multiple wings of more realistic shapes common on aircraft. This modern technique is extended further to apply towards propellers. A method to overcome propeller analysis problems at low airspeeds is presented. This method is compared to more traditional propeller analysis techniques.


Characterization Of Carbon Nanostructured Composite Film Using Photothermal Measurement Technique, Kurt E. Harris May 2018

Characterization Of Carbon Nanostructured Composite Film Using Photothermal Measurement Technique, Kurt E. Harris

All Graduate Theses and Dissertations

Graphene is a form of carbon with unique thermal and structural properties, giving it high potential in many applications, from electronics to driveway heating. Advanced fabrication techniques putting small, graphene-like structures in a polymer matrix could allow for incorporation of some of the benefits of graphene into very lightweight materials, and allow for broader commercialization. Measuring the thermal properties of these thin-film samples is a technical capability in need of development for use with the specific specimens used in this study. Relating those thermal properties to the microstructural composition was the focus of this work.

Several conclusions could be drawn ...


Numerical Evaluation Of Energy Release Rate At Material Interfaces For Fatigue Life Predictions, Robert L. Hendrickson May 2018

Numerical Evaluation Of Energy Release Rate At Material Interfaces For Fatigue Life Predictions, Robert L. Hendrickson

All Graduate Theses and Dissertations

Composite materials are becoming popular in almost all industries. Carbon-fiber and glass-fiber composites are used in aircraft, sports equipment, boats, prosthetics, and wind turbine blades. In all these applications, the composites are subjected to different loads. Loads can take the form of impact or cyclic/fatigue loading, both of which decrease the strength of composites as micro-cracks grow through the composite. Composite laminates are made up of fiber plies (thin layers of fiber) and the fibers are surrounded by a resin like epoxy. It is common for laminates to fail because of delamination growth (plies peeling apart). Small delaminations do ...


Distribution Of Particle Image Velocimetry (Piv) Errors In A Planar Jet, Jaron A. Howell May 2018

Distribution Of Particle Image Velocimetry (Piv) Errors In A Planar Jet, Jaron A. Howell

All Graduate Theses and Dissertations

Particle Image Velocimetry (PIV) is an optical fluid measurement technique used to obtain velocity measurements. Two PIV systems were used to capture data simultaneously and measurement error for the MS PIV system is calculated. An investigation of error distribution is performed to determine when uncertainty estimations fail for the CS PIV-UQ method. Investigation of when results from multi pass PIV processing are achieve were performed so that reliable uncertainty estimations are produced with the CS method. An investigation was also performed which determined that error distributions in PIV systems are correlated with flow shear and particle seeding density. Correlation of ...


Water Surface Impact And Ricochet Of Deformable Elastomeric Spheres, Randy Craig Hurd Dec 2017

Water Surface Impact And Ricochet Of Deformable Elastomeric Spheres, Randy Craig Hurd

All Graduate Theses and Dissertations

Soft and deformable silicone rubber spheres ricochet from a water surface when rigid spheres and disks (or skipping stones) cannot. This dissertation investigates why these objects are able to skip so successfully. High speed cameras allow us to see that these unique spheres deform significantly as they impact the water surface, flattening into pancake-like shapes with greater area. Though the water entry behavior of deformable spheres deviates from that of rigid spheres, our research shows that if this deformation is accounted for, their behavior can be predicted from previously established methods. Soft spheres skip more easily because they deform significantly ...


Fuel Performance Modeling Of Reactivity-Initiated Accidents Using The Bison Code, Charles Pearson Folsom Dec 2017

Fuel Performance Modeling Of Reactivity-Initiated Accidents Using The Bison Code, Charles Pearson Folsom

All Graduate Theses and Dissertations

The Fukushima Daiichi nuclear accidents in 2011 sparked considerable interest in the U.S. to develop new nuclear fuel with enhanced accident tolerance. Throughout the development of these new fuel concepts they will be extensively modeled using specialized computer codes and experimentally tested for a variety of different postulated accident scenarios. One accident scenario of interest, reactivity-initiated accident, is a nuclear reactor event involving a sudden increase in fission rate that causes a rapid increase in reactor power and temperature of the fuel which can lead to the failure of the fuel rods and are lease of radioactive material. The ...


The Influence Of Varying Fiber Stacking Sequence On The Tensile, Impact, And Water Absorption Properties Of Unidirectional Flax/E-Glass Fiber Reinforced Epoxy Composite, Mohammed F. Al-Edhari Dec 2017

The Influence Of Varying Fiber Stacking Sequence On The Tensile, Impact, And Water Absorption Properties Of Unidirectional Flax/E-Glass Fiber Reinforced Epoxy Composite, Mohammed F. Al-Edhari

All Graduate Theses and Dissertations

This thesis includes the study of the mechanical performance of two different types of fibers reinforced hybrid composites. Two kinds of fibers, natural fiber (flax) and synthetic fiber (E-glass), are used to reinforce epoxy resin. To evaluate the effective properties of the hybrid composites, a micromechanical analysis of the structure genome (SG) of a unidirectional fiber hybrid composites is performed using nite element analysis (FEA). Both fibers are assumed to be circular and packed in a hexagonal pattern. The effects of varying volume fractions and fiber locations, of the two fibers, on the elastic properties of the hybrid composites are ...


Aerodynamic Centers Of Arbitrary Airfoils, Orrin Dean Pope Dec 2017

Aerodynamic Centers Of Arbitrary Airfoils, Orrin Dean Pope

All Graduate Theses and Dissertations

The study of designing stable aircraft has been widespread and ongoing since the early days of Orville and Wilbur Wright and their famous Wright Flyer airplane. All aircraft as they fly through the air are subject to minor changes in the forces acting on them. The field of aircraft stability seeks to understand and predict how aircraft will respond to these changes in forces and to design aircraft such that when these forces change the aircraft remains stable. The mathematical equations used to predict aircraft stability rely on knowledge of the location of the aerodynamic center, the point through which ...


Facilitation Of Nanoscale Thermal Transport By Hydrogen Bonds, Lin Zhang Aug 2017

Facilitation Of Nanoscale Thermal Transport By Hydrogen Bonds, Lin Zhang

All Graduate Theses and Dissertations

Thermal transport performance at the nanoscale and/or of biomaterials is essential to the success of many new technologies including nanoelectronics, biomedical devices, and various nanocomposites. Due to complicated microstructures and chemical bonding, thermal transport process in these materials has not been well understood yet. In terms of chemical bonding, it is well known that the strength of atomic bonding can significantly affect thermal transport across materials or across interfaces between materials. Given the intrinsic high strength of hydrogen bonds, this dissertation explores the role of hydrogen bonds in nanoscale thermal transport in various materials, and investigates novel material designs ...


Heat Transfer Analysis Of Localized Heat-Treatment For Grade 91 Steel, Jacob D. Walker Aug 2017

Heat Transfer Analysis Of Localized Heat-Treatment For Grade 91 Steel, Jacob D. Walker

All Graduate Theses and Dissertations

Many of the projects utilizing Grade 91 steel are large in scale, therefore it is necessary to assemble on site. The assembly of the major pieces often requires welding in the assembly; welding drastically changes the superior mechanical properties of Grade 91 steel that it was specifically developed for. Therefore, because of the adverse effects of welding on the mechanical properties of Grade 91, it is necessary to do a localized post weld heat treatment.

In this study a localized post weld heat treatment is used to gather experimental data. The data is then used to derive unknown heat transfer ...


Analysis Of Angles-Only Hybrid Space-Based/Ground-Based Approach For Geosynchronous Orbit Catalog Maintenance, Blythe A. Andrews Aug 2017

Analysis Of Angles-Only Hybrid Space-Based/Ground-Based Approach For Geosynchronous Orbit Catalog Maintenance, Blythe A. Andrews

All Graduate Theses and Dissertations

Geosynchronous Equatorial Orbit (GEO) is critical to Earth communications, weather monitoring, and national defense. Orbit estimation of GEO objects is difficult due to physical constraints placed on ground-based tracking devices such as weather, object range, and tracking frequency restrictions. These constraints are commonly mitigated through the use of two-way signaling devices for cooperative GEO satellites. However, determining the position and velocity of uncooperative GEO satellites and/or objects is more challenging. The objective of this dissertation is to quantify the increased orbital accuracy of objects in the GEO catalog when the Air Force Space Command Space Surveillance Network (AFSPC SSN ...


Nonlinear Photothermal Radiometry And Its Applications To Pyrometry And Thermal Property Measurements, Austin Drew Fleming May 2017

Nonlinear Photothermal Radiometry And Its Applications To Pyrometry And Thermal Property Measurements, Austin Drew Fleming

All Graduate Theses and Dissertations

Accurate temperature and thermal property measurements are critical for the modeling and prediction of heat transfer. In many industries thermal management is a limiting factor of performance, and rely on advanced modeling techniques to develop and design methods to better manage thermal energy. This study expands the thermal property and pyrometry measurement capabilities by developing three new techniques based on thermal emission’s nonlinear dependence on temperature.


Water Entry Impact Dynamics Of Diving Birds, Saberul Islam Sharker May 2017

Water Entry Impact Dynamics Of Diving Birds, Saberul Islam Sharker

All Graduate Theses and Dissertations

Some seabirds (such as Northern Gannets and Brown Boobies) can dive from heights as high as 30 m reaching speeds of up to 24 m/s as they impact the water surface. It is perceived that physical geometry, particularly of the beak, allows them to endure relatively high impact forces that could otherwise kill non-diving birds. Acceleration data from simplified models of diving birds agree with simulated data for one species (Northern Gannet), however, no reliable experimental data with real bird geometries exist for comparison purposes. This study utilizes eleven 3D printed diving birds (five plunge-diving, five surface-diving and one ...


Applications Of Relative Motion Models Using Curvilinear Coordinate Frames, Alex C. Perez May 2017

Applications Of Relative Motion Models Using Curvilinear Coordinate Frames, Alex C. Perez

All Graduate Theses and Dissertations

A new angles-only initial relative orbit determination (IROD) algorithm is derived using three line-of-sight observations. This algorithm accomplishes this by taking a Singular Value Decomposition of a 6x6 matrix to arrive at an approximate initial relative orbit determination solution. This involves the approximate solution of 6 polynomial equations in 6 unknowns. An iterative improvement algorithm is also derived that provides the exact solution, to numerical precision, of the 6 polynomial equations in 6 unknowns. The initial relative orbit algorithm is also expanded for more than three line-of-sight observations with an iterative improvement algorithm for more than three line-of-sight observations. The ...


Role Of Dispersion And Functionalization On Mechanical Properties In Carbon Nanotube - Polymer Composite, Medisetti Sai Praveen Kumar May 2017

Role Of Dispersion And Functionalization On Mechanical Properties In Carbon Nanotube - Polymer Composite, Medisetti Sai Praveen Kumar

All Graduate Theses and Dissertations

Polymer composites with carbon nanotubes (CNT) as filler material is an exciting research area, having a huge potential of offering better mechanical properties. One of the main challenges of using CNT as a filler material is mixing of CNTs within the matrix material, as this mixing determines the strength of the composite. Some of the methods being researched for improving mixing are chemical, mechanical and surfactants. Many studies have suggested high frequency mechanical stirring as the preferred way for better mixing, but challenges exist with finding the proper solvent which can be used for stirring and at the same time ...


Evaluation Of Flux Correction On Three-Dimensional Strand Grids With An Overset Cartesian Grid, Dalon G. Work May 2017

Evaluation Of Flux Correction On Three-Dimensional Strand Grids With An Overset Cartesian Grid, Dalon G. Work

All Graduate Theses and Dissertations

Simulations of fluid flows over complex geometries are typically solved using a solution technique known as the overset meshing method. The geometry is meshed using grid types appropriate to the local geometry in a patchwork fashion, rather than meshing the entire geometry with one type of mesh. The strand-Cartesian approach is a simplification of this process. While high-order accurate solvers on Cartesian grids are simple to implement, strand grids are usually restricted to second-order accuracy, resulting in poor quality solutions. Flux correction is a high-order accurate solution method, specifically designed for use on strand grids. The flux correction method on ...


Characterization Of The Thermal Resistance Of Grain Boundaries Of Cerium Oxide, Jesse Spackman May 2017

Characterization Of The Thermal Resistance Of Grain Boundaries Of Cerium Oxide, Jesse Spackman

All Graduate Theses and Dissertations

Many materials are made up of small crystals, or grains. Grain boundaries are the interfaces between two grains and affect the flow of heat through the material. These interfaces serve to interfere with the energy carriers by scattering or disrupting them. Because of the negative effect these interfaces have on these energy carriers, they inhibit heat flow and act as thermal resistors. The thermal boundary resistance between two grains of the same material is sometimes referred to as the Kapitza resistance, although this term is also used to describe the thermal resistance between solid/solid interfaces of different materials or ...


Mechanical Performance Of Natural / Natural Fiber Reinforced Hybrid Composite Materials Using Finite Element Method Based Micromechanics And Experiments, Muhammad Ziaur Rahman May 2017

Mechanical Performance Of Natural / Natural Fiber Reinforced Hybrid Composite Materials Using Finite Element Method Based Micromechanics And Experiments, Muhammad Ziaur Rahman

All Graduate Theses and Dissertations

A micromechanical analysis of the representative volume element (RVE) of a unidirectional flax/jute fiber reinforced epoxy composite is performed using finite element analysis (FEA). To do so, first effective mechanical properties of flax fiber and jute fiber are evaluated numerically and then used in evaluating the effective properties of ax/jute/epoxy hybrid composite. Mechanics of Structure Genome (MSG), a new homogenization tool developed in Purdue University, is used to calculate the homogenized effective properties. Numerical results are compared with analytical solution based on rule of mixture, Halpin-Tsai as well as Tsai-Hahn equations. The effect of the volume fraction ...