Mechanical Engineering Commons^™

Comparative Performance Analysis: Hers Index Score Dependencies Related To Home Geometries And Operating Assumptions, Florida Solar Energy Center, Philip W. Fairey

FSEC Energy Research Center®

EnergyGauge USA v.3.1.02 is used examine the impact of geometry and operating conditions on comparative simulation analysis techniques that are used to evaluate home energy performance with respect to a standardized reference case. A cohort of homes is simulated using the HERS Index scoring system in 15 U.S. cities that are representative of the 8 International Energy Conservation Code (IECC) climate zones. All of the homes are configured to have the thermal envelope characteristics specified by Table R402.1.1 of the 2012 IECC. All homes are also configured to meet all other mandatory requirements of the 2012 IECC, including 75% high …

Ground-Effect Flight, Troy Schank, Dr. Paul Eastman

Journal of Undergraduate Research

Ground-effect is a well-known phenomenon that occurs as an aircraft approaches the surface of the earth. Flight in ground-effect changes the characteristics of the airflow around the wing causing both positive and negative effects. Though ground-effect is a well-known phenomenon, the details of lift and drag are less understood. I was able to gain an understanding of the details of ground effect from existing studies and learn from my own experiments in this research.

Design And Fabrication Of A Water Tunnel For The Byu Mechanical Engineering Department, Lon M. Stevens, Dr. Daniel R. Maynes

Journal of Undergraduate Research

A water tunnel is essential for visualization, validation, and experimental analysis of the fundamental fluid dynamic behavior of flowing liquids. Water tunnels come in a variety of geometric dimensions, which are dependent upon the type of fluid flows that are of interest. It was proposed for this project that a water tunnel be designed to be used for research and instruction in the Mechanical Engineering Department. The test section of the proposed design will be three feet long, eight inches wide, and eight inches high and manufactured from transparent Plexiglas. Water will flow from one side of the tunnel to …

Systems Integration Of The Goldhelox X-Ray Telescope, Paul F. Eastman, Dr. Thomas J. Utley Jr.

Journal of Undergraduate Research

The GoldHelox X-Ray Telescope is an undergraduate project of the Brigham Young University Physics Department in conjunction with the National Aeronautics and Space Administration. It is a fully autonomous robotic telescope and camera system capable of converting x-rays in the range of 171 angstroms into visible light and capturing the source images on 35mm film. This particular wavelength corresponds to the frequency of x-rays emitted by solar flares erupting from the surface of the sun, and by imaging only the x-rays emitted by the flares themselves, the effect will be to strip away much of the rest of the solar …

Considerations In The Design Of A Prosthetic Foot Using Compliant Design And Analysis Techniques, Kenneth E. Richardson

Journal of Undergraduate Research

The modeling of the human body is not an easy task. Designers of artificial organs and prosthetic devices have the unenviable goal of attempting to duplicate (or at least satisfactorily approximate) the motion and function of the greatest and most powerful machine on the face of the earth. Any new tool that could be used in such design would be valuable and useful. Compliant mechanism theory and design is one such tool.

Anti-Icing Coatings And Methods, Russell G. Alger

Michigan Tech Patents

A method of inhibiting or preventing bonding between snow or ice and a substrate. The method includes applying an adhesive to the substrate, broadcasting an aggregate onto the adhesive, the aggregate having the capacity to receive an anti-icing chemical into the aggregate, and applying the antiicing chemical onto the aggregate so that at least a portion of the anti-icing chemical is received into at least a portion of the aggregate.

Development Of Tailsitter Hover Estimation And Control, Jason M. Beach

Theses and Dissertations

UAVs have become an essential tool in many market segments, particularly the military where critical intelligence can be gathered by them. A tailsitter aircraft is a platform whose purpose is to efficiently merge the range and endurance of fixed-wing aircraft with the VTOL capabilities of rotorcraft and is of significant value in applications where launch and recovery area is limited or the use of launch and recovery equipment is not desirable. Developing autopilot software for a tailsitter UAV is unique in that the aircraft must be autonomously controlled over a much wider range of attitudes than conventional UAVs. Assumptions made …

The Origin Of Interferometric Effect Involving Surface Plasmon Polariton In Scattering Near-Field Scanning Optical Microscopy, Yan Li, Nan Zhou, Edward C. Kinzel, Xifeng Ren, Xianfan Xu

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Scattering near-field scanning optical microscopy (s-NSOM) has been developed to characterize optical near field with spatial resolution on the order of 10 nm. In this work we report investigation of the interferometric patterns commonly occurred in s-NSOM measurements. To reveal the origin of such interference patterns, a simple nano slit is used. Comparing the measured result with a simplified analytical model as well as full-field numerical simulations, it is shown that the interference pattern is predominantly formed by the in-plane component of incidence light and surface plasmon polariton (SPP) launched by the nano slit. This result helps to understand the …

The Effects Of Winglets At Low Speeds, Brian Johansen

Journal of Undergraduate Research

The purpose of an airplane wing is to provide lift by creating a pressure gradient between the top and bottom of the wing. However, this pressure gradient causes some inherent problems at the wing tip. A vortex forms when the high pressure from the bottom side of the wing flows around the wig tip to the top side of the wing. This vortex is detrimental not only to the lift that the wing can produce but to the fuel efficiency of the airplane.

The Role Of Grain Boundary Misorientation In Intergranular Cracking Of Copper, John W. Bean

Journal of Undergraduate Research

This report will summarize the efforts and results of the research conducted by John Bean on the role of grain boundary misorientations in intergranular cracking of copper-based metals. This research was conducted during the period of Sept. 1993 toApril1994. I was not able to prove all that I had originally proposed to do because of certain difficulties I will explain below. My research was ended when the equipment I was using was moved at the end of the 1994 winter semester. This report will briefly describe the purpose of my research and the difficulties that I encountered.

The General Public’S Weather Information-Seeking And Decision-Making Behavior During Tornado Outbreaks In The Oklahoma City Metroplex In May 2013, Chen Ling, Michelle Madison, Jessica Adams, Kevin Warren, Michael Mudd, Kim Graves Wolfinbarger, Lans Rothfusz

Mechanical Engineering Faculty Research

Severe weather impacts the lives of many people. Today's technology allows weather information to be distributed to the general public in many ways. However, it is not clear how people obtain information regarding severe weather, and how they make decisions based on the information. This study surveyed people in the Oklahoma City metroplex about their weather information–seeking and decision-making behaviors during the May 2013 tornado outbreaks. The preliminary results based on 124 survey responses show that people used and trusted television news most to obtain the severe weather information, followed by siren, weather radio, radio, looking at the sky, and …

Femtosecond And Nanosecond Dual-Laser Optical Emission Spectroscopy Of Gas Mixtures, Cheng Hsiang Lin, Zhi Liang, Jun Zhou, Hai-Lung Tsai

Mechanical and Aerospace Engineering Faculty Research & Creative Works

A Method Employing an Integrated Femtosecond (Fs) and Nanosecond (Ns) Dual-Laser System Was Developed to Generate Plasma with Desired Radical Species from Gas Mixtures Via a Fs Laser Pulse and Then to Excite Selected Radical Species to Higher Electronic States using a Wavelength-Tunable Ns Laser Pulse. an Optical Spectrometer Was Used to Measure the Emission Spectra and Identify the Transition from the Excited Electronic State to the Ground State. the Proposed Technique Has Been Demonstrated for an N2-CO2 Mixture with Various Time Delays between the Two Fs and Ns Pulses. the Results Have Indicated that the Population of Selected Radical …

High-Efficiency Thermodynamic Power Cycles For Concentrated Solar Power Systems, Marc T. Dunham, Brian Iverson

Faculty Publications

This paper provides a review of high-efficiency thermodynamic cycles and their applicability to concentrating solar power systems, primarily focusing on high-efficiency single and combined cycles. Novel approaches to power generation proposed in the literature are also highlighted. The review is followed by analyses of promising candidates, including regenerated He-Brayton, regenerated CO2-Brayton, CO2 recompression Brayton, steam Rankine, and CO2-ORC combined cycle. Steam Rankine is shown to offer higher thermal efficiencies at temperatures up to about 600 ˚C but requires a change in materials for components above this temperature. Above this temperature, CO2 recompression Brayton cycles are shown to have very high …

Quadrotors And Accelerometers: State Estimation With An Improved Dynamic Model, Robert C. Leishman, John Macdonald, Randal W. Beard, Timothy W. Mclain

Faculty Publications

The article examines consequences and practical aspects of using an improved dynamic model for quadrotor state estimation with only IMU measurements. The improved model correctly explains the measurements available from the accelerometers on a quadrotor. We give a brief tutorial to explain the difference between accelerometer measurements on a ground vehicle and a quadrotor. We demonstrate several observers based on the improved model to illustrate the estimation improvements available. It is shown that the parameters for this model can be estimated as elements of the state, which makes the model simple to implement and utilize. Finally, we provide hardware results …

Computational Optimization Methods For Modeling The Effect Of Muscle Forces On Bone Strength Adaptation, Catherine Siena Florio

Dissertations

An improved understanding of the mechanical influences that alter the strength of a bone can aid in the refinement of the wide array of currently available techniques to counteract the losses of bone strength that occur due to age or disuse both on Earth and in Space. To address this need, computational modeling methods to quantitatively analyze and compare the effects of mechanical factors on the strength of a targeted bone within a multibone, multimuscle system are developed and implemented in this work. Through a more detailed representation of the system in which the bone acts and the creation of …

Influence Of Lateral Boundaries In Tapped Densification Of Granular Materials, Nathaniel Ching

Theses

Granular systems are widely present in the world. Soil, pharmaceutical pills, and silos filled with grain all are examples of granular systems. Experiments have long established an empirical understanding of granular systems, but an analytical understanding has been much more difficult to establish. One of the behaviors of a granular system that is well documented but poorly understood is the change in density the system undergoes when excited, also known as the densification process.

This thesis investigates the densification process of a tapped granular system using Discrete Element Model (DEM) simulations. Contact interactions in the simulations obey a well-established inelastic …

Sr3<−3xNa3xSi3O9−1.5x (X = 0.45) As A Superior Solid Oxide-Ion Electrolyte For Intermediate Temperature-Solid Oxide Fuel Cells, Tao Wei, Preetam Singh, Yunhui Gong, John B. Goodenough, Yunhui Huang, Kevin Huang

Faculty Publications

We here report that a newly discovered superior oxide-ion conductor Sr_3−3xNa_3xSi₃O_9−1.5x (x = 0.45) (SNS) demonstrates full potential to be a practical solid electrolyte for intermediate temperature-solid oxide fuel cells (IT-SOFCs). It exhibits the highest oxide-ion conductivity with the lowest activation energy among all the chemically stable solid oxide-ion conductors reported. The ionic conductivity is stable over a broad range of partial pressures of oxygen (10⁻³⁰ to 1 atm) for an extended period of time. A SOFC based on a 294 μm thick SNS-electrolyte produces peak power densities …

Using “Expert Employees” To Identify Duties And Tasks For Cadd Technicians In North Central Idaho: Lessons Learned From A Modified Dacum Process, Raymond A. Dixon Ph.D., Linda S. Stricklin Ph.D.

Online Journal for Workforce Education and Development

Objective: We conducted a job analysis to identify the competency profile of an entry level CADD technician in North central Idaho. Background: In 2011, the Clearwater Economic Development Association and NIMA collaborated with Lewis-Clark State College and the University of Idaho in a project to strengthen the capacity of Career and Technology Education (CTE) teachers to teach computer aided drafting and designing (CADD). An application to the National Science Foundation, Advanced Technology Education (NSF ATE) program was made and funding began July of 2011. Method: A modified DACUM was used. A total of seven expert workers from …

Impact Of Residential Mechanical Ventilation On Energy Cost And Humidity Control, Florida Solar Energy Center, Eric Martin

FSEC Energy Research Center®

The DOE Building America program has been conducting research leading to cost effective high performance homes since the early 1990's. Optimizing whole house mechanical ventilation as part of the program's systems engineered approach to constructing housing has been an important subject of the program's research. Ventilation in residential buildings is one component of an effective, comprehensive strategy for creation and maintenance of a comfortable and healthy indoor air environment. The study described in this white paper is based on building energy modeling with an important focus on the indoor humidity impacts of ventilation. The modeling tools used were EnergyPlus version …

Unity Iv: Fuselage Body Design, Analysis, Testing, And Construction, Alexis J. Pabst, Dr. Paul Eastman

Journal of Undergraduate Research

The Unity IV rocket is a twenty-foot tall rocket with a 16.5-inch diameter. It is a super-sonic, hybrid rocket that uses a solid propellant and liquid oxidizer. The rocket has been designed and built by students from three Utah universities. It is intended to take an instrumentation package super-sonically to an altitude of 130,000 ft and return it safely to earth.

Comparing Nox Emissions Of Diesel Fuel And Oxygenated Fuels, Timothy M. Allred, Dr. Dale R. Tree

Journal of Undergraduate Research

The emissions produced by both passenger and commercial vehicles are a significant contributor to pollution problems that face many cities and areas around the world. One of these pollutants is known as NOx, which refers to the chemical compounds NO2 and NO. These gases are formed when fuel is burned at high temperatures and are an undesirable by-product of the internal combustion engine. Nitrogen dioxide reacts in air to form acid rain as well as contributing to ground-level ozone and smog.

A New Stereology, Ryan J. Larsen, Dr. Brent L. Adams

Journal of Undergraduate Research

Much research in recent years has focused on producing polycrystalline materials with high numbers of special grain boundaries. Special grain boundaries are defined as boundaries with desirable properties, such as resistance to corrosion, cracking, or precipitation. Most researchers describe grain boundary geometry only with the three parameters of misorientation between adjacent crystal lattices. Although misorientation data have been successfully linked to some properties, knowledge of misorientation alone is insufficient to predict grain boundary energy, and can thus provide only a first-order approximation of a boundary’s properties.

Developing Mechanisms As Liga Microstructures, Jordan E. Brough, Dr. Larry Howell

Journal of Undergraduate Research

Microelectromechanical Systems (MEMS) is a rapidly developing field which uses technology similar to that used to carve out the millions of tiny channels found in today’s computer processors. MEMS, however, uses this technology to make mechanical structures and mechanisms instead of electrical pathways. My effort over the past eight months has been to research the developing LIGA MEMS design (an electromolding process), fabricate a test structure via the LIGA technology, and in the process establish a working relationship between Sandia National Laboratories California (a leader in MEMS) and BYU’s microengineering team.

Use Of Linear Analysis Of Microstructures In Defining Performance Closures For Highly Constrained Mechanical Design, Mark Lyon, Dr. Brent L. Adams

Journal of Undergraduate Research

Using methods described by Adams1, the design of a compliant beam was modeled in a multidimensional Fourier design space. A compliant beam is one that achieves motion through bending. The motivation for the problem was a bicycle derailleur. A compliant beam could replace the entire rear derailleur if a large amount of flexibility could be obtained and yet have a relatively strong force when displaced to return the beam to its original position. The compliant derailleur would be simpler and cheaper than current derailleur designs. In general, metals are too stiff and plastics are too weak for this application. The …

A Compliant Orthoplanar Piezoelectric Actuator, Aaron Shelley, Dr. Larry Howell

Journal of Undergraduate Research

This research focused on developing a new actuator/motor by integrating two previously unrelated technologies. In the past, piezoelectric crystals have been used primarily to measure acceleration in the engineering field, because of their unique nature of generating electricity when changes in their position occur. Modern researchers now use piezoelectric crystals in the opposite way, in that they put electricity through the crystals, causing them to expand or contract. The ability to cause the crystals to expand/contract merely by having a voltage difference across the crystal represents a whole new method of creating actuators/motors.

Design Of Equipment To Test Compliant Centrifugal Clutches, Nathan B. Crane, Dr. Larry L. Howell

Journal of Undergraduate Research

A compliant mechanism is a mechanism in which some or all motion comes from deflection of its members. Several years ago, a one piece centrifugal clutch based on a compliant mechanism was developed and implemented in several products. It offers many cost and assembly advantages over traditional clutch designs containing at least five components.

The Developing Length Of Electro-Osmotic Flow, Joseph Scott Tenny, Dr. Daniel Maynes

Journal of Undergraduate Research

Recent advancements in technology have created the need for increased understanding of fluid flow in microtubes with a diameter of a 100μm or less. These types of flows can occur in many practical applications, one of which is a concept proposed for DNA analysis called “lab on a chip.” At this physical scale, the pressures required to drive the flow of the fluid are often too large for any type of potential application. An alternative approach to driving the fluid through a microtube is to use electro-osmosis. This type of flow uses an applied voltage potential to drive the fluid …

Optimization Of Wind Turbine Airfoils/Blades And Wind Farm Layouts, Xiaomin Chen

All Theses and Dissertations (ETDs)

Shape optimization is widely used in the design of wind turbine blades. In this dissertation, a numerical optimization method called Genetic Algorithm (GA) is applied to address the shape optimization of wind turbine airfoils and blades. In recent years, the airfoil sections with blunt trailing edge (called flatback airfoils) have been proposed for the inboard regions of large wind-turbine blades because they provide several structural and aerodynamic performance advantages. The FX, DU and NACA 64 series airfoils are thick airfoils widely used for wind turbine blade application. They have several advantages in meeting the intrinsic requirements for wind turbines in …

Nasa Human Exploration Rover Challenge, Estelle Fortes, Aaron Taylor, Caitlin Talerico, Jessica Chow, Jessica Turcios, Johnnie Perry, Joshua Beck, Juana Cecilia Martin-Gonzalez, Lisa Ferguson, Michaela Branscomb, Mo Sabliny, Raeann Vansickle, Sarah Pearson, Sierra Dryer, Zach Henney, Brenda Haven

Aviation / Aeronautics / Aerospace International Research Conference

NASA's Great Moonbuggy Race, held annually in at the Marshall Space Flight Center in Huntsville, Alabama, is an engineering design challenge that asks teams of student engineers to design a human-­‐powered vehicle capable of traversing a simulated lunar surface. However, there is an interesCng sCpulaCon in the design of the moonbuggy: it must be able to be transported in a 4x4x4 foot cube, echoing the design constraint faced by the engineers who built the Lunar Roving Vehicles used by the astronauts of the later Apollo missions. The vehicle in this proposal, Ocelot, designed by the Society of Women Engineers at …

Applications Of Long-Wave Thermal Infrared Imagers On Unmanned Aerial Systems For First Responders, Nick Harris, Lorenzo Coykendall

Aviation / Aeronautics / Aerospace International Research Conference

The Embry-Riddle Prescott UAS Team will design, build, and test three Unmanned Aerial Systems (UAS) for competing in the student UAS Competition June 18 - 22 in Patuxent River, MD hosted by the Association for Unmanned Vehicle Systems International (AUVSI).

The team will design and build these unmanned aircraft to carry a five-pound payload, sustain flight for at least forty minutes, and be hand-launchable and rugged; they will be constructed from composite materials and will be fully autonomous through the use of open-source autopilots.