Mechanical Engineering Commons^™

Monte Carlo Uncertainty Analysis For Photothermal Radiometry Measurements Using A Curve Fit Process, Kyle Horne, Austin Fleming, Heng Ban

Utah Space Grant Consortium

Photothermal Radiometry (PTR) has become a popular method to measure thermal properties of layered materials. Much research has been done to determine the capabilities of PTR, but with little uncertainty analysis. This study performs a Monte Carlo uncertainty analysis to quantify uncertainty of film diffusivity and effusivity measurements, presents a sensitivity study for each input parameter, compares linear and logarithmic spacing of data points on frequency scans, and investigates the validity of a 1-D heat transfer assumption.

Transformable Wheelchair, Benjamin Shurtz

Undergraduate Honors Capstone Projects

This report includes the development, design, and analysis of a transformable wheelchair. There was a need to design and build a wheelchair that transformed to be pushed, pulled, or self-propelled. This design meets the need of physically restricted wheelchair users who frequent simple hiking trails without needing to move to a secondary off-road capable device. Documentation for concepts, analysis, and completed design details follows.

Towed Water Turbine Computational Fluid Dynamics Analysis, Robert G. Maughan

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Computational fluid dynamics can be used to predict operating conditions of towed water turbines which are used in long distance sailing applications to meet electrical demands. The design consists of a turbine fastened to a shaft which is attached to a generator by a rope. The turbine is pulled in water behind a sailboat and torque is transmitted through the rope to turn the onboard generator and produce power. Torque curves from an alternator, generator, and from computational fluid dynamics were used to determine the operating spin rate and output power of the system. On-water tests were conducted to determine …

Miniature Wire Boom System For Cubsat Application, Keith R. Bradford

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Small satellites and especially CubeSats are becoming more widely used to study the space environment. The Ionosphere is one region of particular interest, more specifically the altitude region of 85 km to 600 km. Small satellites are particularly useful for studying this region of the Earth’s atmosphere since the effects of aerodynamic drag on a CubeSat are much less than those on a larger more traditional satellite, thus the lifespan of a CubeSat in this region is much longer. In order to observe the electric field in space, the electric potential between various points needs to be measured. These measurements …

Energy-Vorticity Turbulence Model With Application To Flow Near Rough Surfaces, W. F. Phillips, E. B. Fowler, Doug F. Hunsaker

Mechanical and Aerospace Engineering Faculty Publications

Based on a more direct analogy between turbulent and molecular transport, a foundation is presented for an energy–vorticity turbulence model. Whereas traditional k-εk-ε, k-ωk-ω, and k-ζk-ζ models relate the eddy viscosity to a dissipation length scale associated with the smaller eddies having the highest strain rates, the proposed model relates the eddy viscosity to a mean vortex wavelength associated with the larger eddies primarily responsible for turbulent transport. A rigorous development of the turbulent-energy-transport equation from the Navier–Stokes equations includes exact relations for the viscous dissipation and molecular transport of turbulent kinetic energy. Application of Boussinesq’s analogy between turbulent and …

Analysis And Design Of A Thermal Capacitor For Use In The Food Industry, Karen Nielson

Undergraduate Honors Capstone Projects

Team Hot Stuff is working with Thermal Management Technologies (TMT) of Logan, UT to explore the concept of a thermal capacitor serving platter. With the funding from TMT, Hot Stuff will design, build, and test a prototype serving platter. This report is written by Hot Stuff for MAE 4800, Capstone Design I; it covers the design and analysis of a serving platter.

Variational Asymptotic Method For Unit Cell Homogenization Of Thermomechanical Behavior Of Composite Materials, Chong Teng

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

To seek better material behaviors, the research of material properties has been massively carried out in both industrial and academic fields throughout the twentieth century. Composite materials are known for their abilities of combining constituent materials in or- der to fulfill the desirable overall material performance. One of the advantages of composite materials is the adjustment between stiffness and lightness of materials in order to meet the needs of various engineering designs. Even though the finite element analysis is mature, composites are heterogeneous in nature and can present difficulties at the structural level with the acceptable computational time. A way …

Hybrid Photothermal Technique For Microscale Thermal Conductivity Measurement, Zilong Hua

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In nuclear reactors, the thermal energy generated from the nuclear reactions needs to be transferred all the way through the core of the fuels to the surrounding steam to be utilized. Therefore, thermal conductivity is considered an important thermophysical property of the fuel which needs to be measured. The nuclear fuel microstructure is known to be damaged by neutronirradiation, which can result in sharp, local changes of thermal conductivity. However, most existing thermal conductivity measurement techniques of nuclear fuel are not able to make high spatial-resolution measurements. The objective of this study was to develop a non-contact thermal conductivity measurement …

Thermo-Piezo-Electro-Mechanical Simulation Of Algan (Aluminum Gallium Nitride) / Gan (Gallium Nitride) High Electron Mobility Transistor, Lorin E. Stevens

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Due to the current public demand of faster, more powerful, and more reliable electronic devices, research is prolific these days in the area of high electron mobility transistor (HEMT) devices. This is because of their usefulness in RF (radio frequency) and microwave power amplifier applications including microwave vacuum tubes, cellular and personal communications services, and widespread broadband access. Although electrical transistor research has been ongoing since its inception in 1947, the transistor itself continues to evolve and improve much in part because of the many driven researchers and scientists throughout the world who are pushing the limits of what modern …

The Dynamic Analysis Of A Composite Overwrapped Gun Barrel With Constrained Viscoelastic Damping Layers Using The Modal Strain Energy Method, Braydon Day Hall

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

By using composite materials and rubber overwrapped onto a steel liner, a new design for a gun barrel is investigated. Multiple configurations are analyzed and compared using the Finite Element Method and analytical solutions. By alternating layers of composite material and rubber over the steel liner, different reactions in the barrel are obtained when subjected to identical internal pressures from a projectile being fired. The ideal reaction desired from creating this new gun barrel is to dissipate energy more effectively than gun barrels made entirely of steel or overwrapped with just a composite material. The analyses show that multiple thin …

Computational Fluid Dynamics Validation Of Buoyant Turbulent Flow Heat Transfer, Jared M. Iverson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Computational fluid dynamics (CFD) is commonly used to visualize and understand complicated fluid flow and heat transfer in many industries. It is imperative to validate the CFD computer models in order to avoid costly design choices where experimentation cannot be used to ratify the predictions of computer models. Assessments of CFD computer models in the literature conclude that significant errors occur in computer model predictions of fluid flow influenced by buoyancy forces.

The Experimental Fluid Dynamics Laboratory at Utah State University constructed a wind tunnel with which to perform experiments on buoyancy induced fluid flow. The experiments measured the heat …

Verification And Validation Of The Spalart-Allmaras Turbulence Model For Strand Grids, Oisin Tong

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The strand-Cartesian grid approach is a unique method of generating and computing fluid dynamic simulations. The strand-Cartesian approach provides highly desirable qualities of fully-automatic grid generation and high-order accuracy. This thesis focuses on the implementation of the Spalart-Allmaras turbulence model to the strand-Cartesian grid framework. Verification and validation is required to ensure correct implementation of the turbulence model.

Mathematical code verification is used to ensure correct implementation of new algorithms within the code framework. The Spalart-Allmaras model is verified with the Method of Manufactured Solutions (MMS). MMS shows second-order convergence, which implies that the new algorithms are correctly implemented.

Validation …

Analysis Of Star Identification Algorithms Due To Uncompensated Spatial Distortion, Steven Paul Brätt

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

With the evolution of spacecraft systems, we see the growing need for smaller, more affordable, and robust spacecrafts that can be jettisoned with ease and sent to sites to perform a myriad of operations that a larger craft would prohibit, or that can be quickly manipulated from performing one task into another. The developing requirements have led to the creation of Nano-Satellites, or CubeSats. The question then remains, how to navigate the expanse of space with such a minute spacecraft? A solution to this is using the stars themselves as a means of navigation. This can be accomplished by measuring …

Experimental Studies Of Vertical Mixing Patterns In Open Channel Flow Generated By Two Delta Wings Side-By-Side, Garrett Vaughan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Algae-derived biofuels is a hot topic of research interest when it comes to renewable energy applications. Algae can be grown in open systems that are low-cost, easy to maintain, and open to the environment. However, algae does not grow very dense in these systems. Mixing is an important factor in growing algae. If mixing were to be improved in open systems, the algae may be able to grow more dense. Certain studies show that placing a mechanical device such as an airfoil or airplane wing in the water will be able to increase the capability of mixing in the open …

Design And Optimization Of A Thermal Capacitor, Karen Nielson, Jordan Tracy Cox

Undergraduate Honors Capstone Projects

Team Hot Stuff designed a thermal capacitor for Senior Design I at Utah State University. This thermal capacitor is intended for use in the food service industry as a low-cost alternative to chafers. Chafers are platters which use oil burners to keep food warm. The client for this thermal capacitor is Thermal Management Technologies (TMT), a company specializing in thermal science solutions whose mission is “to provide simple, practical thermal science solutions to a wide range of platforms including: Industry, Defense, and Space”¹. The founder and president of TMT, Dr. J. Clair Batty, serves as a mentor for …

Assess The Accuracy Of The Variational Asymptotic Plate And Shell Analysis Using The Generalized Uni, Luciano Demasi, Wenbin Yu

Mechanical and Aerospace Engineering Faculty Publications

The accuracy of the Variational Asymptotic Plate and Shell Analysis (VAPAS) is assessed against several higher order, zig zag and layerwise theories generated by using the invariant axiomatic framework denoted as Generalized Unified Formulation (GUF). These theories are also compared against the elasticity solution developed for the case of a sandwich structure with high Face to Core Stiffness Ratio. GUF allows to use an infinite number of axiomatic theories (Equivalent Single Layer theories with or without zig zag effects and Layerwise theories as well) with any combination of orders of the displacements and it is an ideal tool to precisely …

Dnad, A Simple Tool For Automatic Differentiation Of Fortran Codes Using Dual Numbers, Wenbin Yu, Maxwell Blair

Mechanical and Aerospace Engineering Faculty Publications

DNAD (dual number automatic differentiation) is a simple, general-purpose tool to automatically differentiate Fortran codes written in modern Fortran (F90/95/2003) or legacy codes written in previous version of the Fortran language. It implements the forward mode of automatic differentiation using the arithmetic of dual numbers and the operator overloading feature of F90/95/2003. Very minimum changes of the source codes are needed to compute the first derivatives of Fortran programs. The advantages of DNAD in comparison to other existing similar computer codes are its programming simplicity, extensibility, and computational efficiency. Specifically, DNAD is more accurate and efficient than the popular complex-step …

Thermal Conductivity Profile Determination In Proton-Irradiated Zrc By Spatial And Frequency Scanning Thermal Wave Methods, C. Jensen, M. Chirtoc, N. Horny, J. S. Antoniow, H. Pron, Heng Ban

Mechanical and Aerospace Engineering Faculty Publications

Using complementary thermal wave methods, the irradiation damaged region of zirconium carbide (ZrC) is characterized by quantifiably profiling the thermophysical property degradation. The ZrC sample was irradiated by a 2.6 MeV proton beam at 600 °C to a dose of 1.75 displacements per atom. Spatial scanning techniques including scanning thermal microscopy (SThM), lock-in infrared thermography (lock-in IRT), and photothermal radiometry (PTR) were used to directly map the in-depth profile of thermal conductivity on a cross section of the ZrC sample. The advantages and limitations of each system are discussed and compared, finding consistent results from all techniques. SThM provides the …

Investigation Of The Noise Floor Of The Standard Piv Cross-Correlation Algorithm, Kyle L. Jones

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Particle image velocimetry (PIV) is a powerful measurement technique used to acquire instantaneous measurements of entire flow fields at a given instant in time. Quantifying the uncertainty and error in PIV is a critical part of realizing the full potential of PIV as a flow measurement technique.

The noise floor of PIV is the minimum amount of random error that can be achieved for a particular standard cross-correlation (SCC) algorithm. The noise floor of the SCC used by DaVis in correlating image pairs is explored. Two methods for creating image pairs for correlation are compared, namely pseudo image pairs and …

Performance Characterization Of Complex Fuel Port Geometries For Hybrid Rocket Fuel Grains, Andrew Bath

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Extensive research in hybrid rocket motors has taken place at the department of Mechanical and Aerospace Engineering at USU (Utah State University) in the last several years. USU has one of the few facilities in the country capable of static-test firing rocket motors on-campus, which allows for fast-paced testing and development not available elsewhere. Research has involved investigating propulsion devices for a range of applications, including micro-satellite thrusters, hot-gas generators, and even jet-assisted takeoff kick motors. Hybrid motors have the advantage of safety over any other chemical propulsion. Since the fuel and oxidizer are stored seperately, they are relatively inert …

Closed-Loop Thrust And Pressure Profile Throttling Of A Nitrous Oxide/Hydroxyl-Terminated Polybutadiene Hybrid Rocket Motor, Zachary W. Peterson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Hybrid motors that employ non-toxic, non-explosive components with a liquid oxidizer and a solid hydrocarbon fuel grain have inherently safe operating characteristics. The inherent safety of hybrid rocket motors offers the potential to greatly reduce overall operating costs. Another key advantage of hybrid rocket motors is the potential for in-flight shutdown, restart, and throttle by controlling the pressure drop between the oxidizer tank and the injector. This research designed, developed, and ground tested a closed-loop throttle controller for a hybrid rocket motor using nitrous oxide and hydroxyl-terminated polybutadiene as propellants. The research simultaneously developed closed-loop throttle algorithms and lab scale …

Design And Construction Of A Tunable Light Source With Light Emitting Diodes For Photosynthetic Organisms, Nathan Phillipps

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This thesis describes and documents the design and construction of a light source which is tunable and has the ability to mimic the spectral output of the sun in the photosynthetic active radiation range (400 - 700 nm). To adjust the spectral output at different wavelengths different types of LEDs were chosen and combined. This thesis describes the design, construction, testing, and suggestions for further improvements to this light source. The light source is comprised of 900 LEDs with 26 different peak wavelengths within the photosynthetically active radiation range. The light source is made tunable through the use of a …

Development Of A Ripple Rejection Controller For Dc Commutated Motors, Spencer M. Atkin

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

The requirement of modern systems to be quiet and run smoothly increases production costs. The manufacture and purchase of high quality motors that meet these demands becomes increasingly costly. By using the ever increasing computer power available in micro-controllers, at the same costs, it is possible to use current sensing to develop control adjustments which decrease power ripples caused by the commutators of basic DC commutated motors. These ripples if left unmitigated propagate through to torque ripples which then increase the acoustic noise level present.

Merrill-Cazier Library Gas Exhibition, Betty Rozum, Andrew Wesolek, Pamela N. Martin

Education and Outreach

This exhibition, presented in the Merrill-Cazier Library, captured the history and accomplishments of the GAS program. Click the download button to see a PowerPoint presentation featuring images and text from the exhibition.

Application Of An Energy-Vorticity Turbulence Model To Fully Rough Pipe Flow, E. B. Fowler, Doug F. Hunsaker, W. F. Phillips

Mechanical and Aerospace Engineering Faculty Publications

Based on a more direct analogy between turbulent and molecular transport, a foundation was recently presented for an energy-vorticity turbulence model. The new turbulent-energytransport equation contains two closure coefficients; a viscous-dissipation coefficient and a turbulent-transport coefficient. To help evaluate the closure coefficients and provide insight into the energy-vorticity turbulence variables, fully rough pipe flow is considered. For this fully developed flow, excellent agreement with experimental data for velocity profiles and friction factors is attained over a wide range of closure coefficients, provided that a given relation between the coefficients is maintained.

Re-Configurable Putting Green, Matthew Ralphs

Undergraduate Honors Capstone Projects

This report discusses the design of a prototype transformable putting green that can be programmed to recreate the topography of any putting green. The goal of the design was to give a realistic putting experience with real topography in an indoor environment. This report discusses the design of a pair of 4’x4’ module prototypes; a commercial implementation of this design would utilize a number of modules to create putting greens on a more realistic scale (example 12’x32’). The design of a full size transformable putting green necessitates a topographical range of up to 30”. After initial concepts and preliminary designs …

Streambed Thermal Property Instrument (Spi), James Alwel Dayie

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

The purpose of this research, the Streambed thermal Property Instrument (SPI) is to determine the applicability of this instrument for in situ thermal (conductivity and diffusivity) and porous flow (magnitude and direction) measurements. Currently, no such thermal instrument exists for such in situ measurements and the reason for developing this unique instrument, the SPI to fill the technology gap in sediment thermal property measurement devices. Prior to testing the instrument under controlled laboratory conditions to determine its functionality through a series of static and flow tests, the instrument was designed and built. A lab-sized version of an actual river called …

Heater Geometry And Heat Flux Effects On Subcooled, Thin Wire, Nucleate Pool Boiling In Microgravity, Troy Munro

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this thesis is to study the effects of microgravity, surface geometry, and heat dissipation per unit area (heat flux) on boiling heat transfer. Boiling is able to move a significant amount of heat for a small area in comparison to other heat transfer methods. Space systems could benefit from the development of thermal management systems that use boiling heat transfer because they would be smaller, more robust, and less expensive. However, boiling is an extremely complicated process which has no comprehensive models to predict its behavior. Multiple correlations have been developed which relate heat transfer efficiencies to …

Investigation Of Relative Importance Of Some Error Sources In Particle Image Velocimetry, Jeff R. Harris

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Particle image velocimetry (PIV) is an optical technique used to measure fluid velocity. PIV measurements have many sources that create uncertainty in the velocity results. The objective of this report is to investigate some commonly cited uncertainty sources and to show methods than can be used to find the value of the uncertainty sources. These sources are: magnification, calibration, perspective, resolution and the computation scheme. Experiments were conducted to find the impact that sources have on the velocity measurements. Several methods are presented to demonstrate how to measure the uncertainty of error for a PIV experiment. Some error quantities are …

Effect Of Orifice Shape On Synthetic Jet Efficiency, David J. Nani

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

A synthetic jet is formed by periodic oscillation of a fluid through an orifice. The oscillatory motion is driven by diaphragm or other driver. Previous studies have demonstrated that synthetic jet formation and time-averaged cavity pressure are a function of the orifice shape. Traditionally, the performance of the jet is evaluated with varying configurations of fixed driver input voltage or fixed driver displacement. Neither of these measures accurately reflect the efficiency of the actuator. Defining efficiency as "desired output divided by required input," these traditional measures may not account for increase in required driving current or force.

A sharp inside …