Open Access. Powered by Scholars. Published by Universities.®
- Discipline
-
- Manufacturing (71)
- Civil and Environmental Engineering (36)
- Construction Engineering and Management (34)
- Other Mechanical Engineering (33)
- Electrical and Computer Engineering (24)
-
- Physical Sciences and Mathematics (12)
- Business (7)
- Architecture (6)
- Arts and Humanities (6)
- Chemical Engineering (6)
- Computer Sciences (6)
- Electro-Mechanical Systems (6)
- Engineering Science and Materials (6)
- Medicine and Health Sciences (6)
- Physics (6)
- Acoustics, Dynamics, and Controls (5)
- Biomechanical Engineering (5)
- Biomedical Engineering and Bioengineering (5)
- Communication Sciences and Disorders (5)
- Energy Systems (5)
- Engineering Physics (5)
- Music (5)
- Other Architecture (5)
- Other Physics (5)
- Signal Processing (5)
- Social and Behavioral Sciences (5)
- Speech and Hearing Science (5)
- Audio Arts and Acoustics (4)
- Keyword
-
- UAV (60)
- Unmanned aircraft (51)
- Compliant mechanisms (50)
- Optimization (39)
- MEMS (35)
-
- Origami (35)
- Friction stir welding (25)
- CFD (22)
- Microstructure (21)
- CAD (20)
- Compliant (20)
- Compliant mechanism (20)
- Design (20)
- Heat transfer (20)
- Mechanical engineering (20)
- Aerodynamics (16)
- FSW (16)
- Superhydrophobic (15)
- Aluminum (14)
- EVTOL (14)
- UAS (14)
- Computational fluid dynamics (13)
- Modeling (13)
- Vocal folds (13)
- Additive manufacturing (12)
- Grain boundaries (12)
- Carbon nanotubes (11)
- Compliant Mechanisms (11)
- Manufacturing (11)
- Mechanism (11)
- Publication Year
- Publication
-
- Theses and Dissertations (724)
- Faculty Publications (400)
- Journal of Undergraduate Research (164)
- ScholarsArchive Data (13)
- Student Works (11)
-
- Undergraduate Honors Theses (10)
- Biomedical Engineering Western Regional Conference (9)
- Directivity (5)
- Reviews, Analyses, and Instructional Studies in Electrochemistry (RAISE) (2)
- BYU Research Development Office Research Networking Conference (1)
- Journal of Nonprofit Innovation (1)
- Library/Life Sciences Undergraduate Poster Competition 2022 (1)
- Marriott Student Review (1)
- Publication Type
- File Type
Articles 541 - 570 of 1342
Full-Text Articles in Mechanical Engineering
A New Stereology, Ryan J. Larsen, Dr. Brent L. Adams
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
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
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
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
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
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 …
The Effects Of Tool And Temperature Parameters On Grain Growth In Friction Stir Welded 7050 And 7475 Aluminum, Kevin Allen Schwendiman, Dr. Tracy Nelson, Dr. Carl Sorenson
The Effects Of Tool And Temperature Parameters On Grain Growth In Friction Stir Welded 7050 And 7475 Aluminum, Kevin Allen Schwendiman, Dr. Tracy Nelson, Dr. Carl Sorenson
Journal of Undergraduate Research
The Welding Institute (TWI) in Cambridge, England invented friction stir welding (FSW) late in 1991. TWI applied in December of that year for worldwide patent protection. The friction stir welding process is simple, energy-efficient and inexpensive relative to other welding methods. FSW can be implemented to make high quality welds with the most versatility – meaning the process can be used in almost all positions. Tensile, fatigue and bending tests have demonstrated that the properties of friction stir welded materials are superior to those made by other welding methods such as fusion or arc welding.
Low Reynolds Number Aerodynamics For Micro Air-Vehicles (Mav), Paul Nelson, Chad Lebaron, Bart Frischknecht, Kristopher Danielson, Jerry Bowman
Low Reynolds Number Aerodynamics For Micro Air-Vehicles (Mav), Paul Nelson, Chad Lebaron, Bart Frischknecht, Kristopher Danielson, Jerry Bowman
Journal of Undergraduate Research
Very little aerodynamic data exists for Reynolds numbers less than 100,000. It is common for there to be a large discrepancy between numerically predicted and experimental airfoil performance, especially at very low Reynolds numbers. In this research, a low Reynolds number airfoil was developed based on aerodynamic measurements.
An Examination Of The Usefulness Of Lapping For Reducing Tip Leakage In Scroll Compressors, Jared W. Jensen, Paul Eastman, Jason Hugenroth
An Examination Of The Usefulness Of Lapping For Reducing Tip Leakage In Scroll Compressors, Jared W. Jensen, Paul Eastman, Jason Hugenroth
Journal of Undergraduate Research
Scroll compressors are unique in that the working fluid (in most cases, Freon or Puron™) is continuously compressed in an involute wrap. The geometry of the two scrolls is such that the gas is compressed towards the center in progressively smaller chambers as one scroll orbits the other. Before the gas is discharged, the involute returns to an intake state allowing the compressor to compress several “pockets” of refrigerant at the same time.
Computer Simulation Of Microstructures Based On Two-Point Correlation Functions, Benjamin L. Hansen, Dr. Brent Adams
Computer Simulation Of Microstructures Based On Two-Point Correlation Functions, Benjamin L. Hansen, Dr. Brent Adams
Journal of Undergraduate Research
A great amount of variance exists in the properties of any material. The ability to accurately predict these properties allows for designers to find the “best” material in highly constrained design situations. Many properties, such as elasticity and conductivity, are relatively insensitive to grain boundary interfaces and dislocations, and are thus accurately predicted by simple averaging techniques with a first-order description of the microstructure. However, many properties that effect lifetime to failure such as plastic yielding, intergranular stress corrosion cracking, and embrittlement are sensitive to dislocations and grain boundary interfaces. Therefore, second-order descriptions of the microstructures are needed to estimate …
Use Of A Gradient-Based Search Method To Reconstruct The Temperature Profile Along An Optical Fiber Thermometer, David G. Barker, Dr. Matthew R. Jones
Use Of A Gradient-Based Search Method To Reconstruct The Temperature Profile Along An Optical Fiber Thermometer, David G. Barker, Dr. Matthew R. Jones
Journal of Undergraduate Research
Advances in the area of Optical Fiber Thermometry (OFT) are leading to more accurate temperature measurements in high-temperature environments. A typical OFT application is when the tip of an optical fiber is inserted into an environment where the temperature is to be measured. The other end of the fiber is attached to an optical system where light from the fiber is measured (see Figure 1). From the light emission measurements, the temperature at the heated tip of the fiber can be inferred.1
Sensitivity Analysis Of Wind Plant Performance To Key Turbine Design Parameters: A Systems Engineering Approach, Katherine Dykes, Andrew Ning, Ryan King, Peter Graf, George Scott, Paul Veers
Sensitivity Analysis Of Wind Plant Performance To Key Turbine Design Parameters: A Systems Engineering Approach, Katherine Dykes, Andrew Ning, Ryan King, Peter Graf, George Scott, Paul Veers
Faculty Publications
This paper introduces the development of a new software framework for research, design, and development of wind energy systems which is meant to 1) represent a full wind plant including all physical and nonphysical assets and associated costs up to the point of grid interconnection, 2) allow use of interchangeable models of varying fidelity for different aspects of the system, and 3) support system level multidisciplinary analyses and optimizations. This paper describes the design of the overall software capability and applies it to a global sensitivity analysis of wind turbine and plant performance and cost. The analysis was performed using …
Long Life Electrochemical Diodes For Continuous Electrowetting, Mehdi Khodayari, Ben Hahne, Nathan B. Crane
Long Life Electrochemical Diodes For Continuous Electrowetting, Mehdi Khodayari, Ben Hahne, Nathan B. Crane
Faculty Publications
The rate of electrochemical reactions in some systems varies with the polarity of the overpotential on the working electrode, introducing diode-like behavior at the electrode/electrolyte interface. However, with repeated bipolar cycling, the electrochemical current damages the electrodes. We have connected electrochemical diodes in series with opposing polarities to reduce the diode current while charging a capacitive circuit. We have previously used this capacitive circuit arrangement to actuate aqueous droplets continuously using the electrowetting (EW) effect. In this study, the performance of electrochemical diodes under repeated voltage cycles is investigated. Aluminum and titanium electrodes in contact with three electrolyte solutions (0.1 …
System-Level Simulation Of A Solar Power Tower Plant With Thermocline Thermal Energy Storage, Scott M. Flueckiger, Brian D. Iverson, Suresh V. Garimella, James E. Pacheco
System-Level Simulation Of A Solar Power Tower Plant With Thermocline Thermal Energy Storage, Scott M. Flueckiger, Brian D. Iverson, Suresh V. Garimella, James E. Pacheco
Faculty Publications
A thermocline tank is a low-cost thermal energy storage subsystem for concentrating solar power plants that typically utilizes molten salt and quartzite rock as storage media. Longterm thermal stability of the storage concept remains a design concern. A new model is developed to provide comprehensive simulation of thermocline tank operation at low computational cost, addressing deficiencies with previous models in the literature. The proposed model is then incorporated into a system-level model of a 100 MWe power tower plant to investigate storage performance during long-term operation. Solar irradiance data, taken from measurements for the year 1977 near Barstow, CA, are …
Review Of High-Temperature Central Receiver Designs For Concentrating Solar Power, Brian D. Iverson, Clifford K. Ho
Review Of High-Temperature Central Receiver Designs For Concentrating Solar Power, Brian D. Iverson, Clifford K. Ho
Faculty Publications
This paper reviews central receiver designs for concentrating solar power applications with high-temperature power cycles. Desired features include low-cost and durable materials that can withstand high concentration ratios (~1000 suns), heat-transfer fluids that can withstand temperatures > 650°C, high solar absorptance, and low radiative and convective heat losses leading to a thermal efficiency > 90%. Different receiver designs are categorized and evaluated in this paper: (1) gas receivers, (2) liquid receivers, and (3) solid particle receivers. For each design, the following information is provided: general principle and review of previous modeling and testing activities, expected outlet temperature and thermal efficiency, benefits, perceived …
Effect Of Full-Annular Pressure Pulses On Axial Turbine Performance, Mark H. Fernelius
Effect Of Full-Annular Pressure Pulses On Axial Turbine Performance, Mark H. Fernelius
Theses and Dissertations
Pulse detonation engines show potential to increase the efficiency of conventional gas turbine engines if used in place of the steady combustor. However, since the interaction of pressure pulses with the turbine is not yet well understood, a rig was built to compare steady flow with pulsing flow. Compressed air is used in place of combustion gases and pressure pulses are created by rotating a ball valve with a motor. This work accomplishes two main objectives that are different from previous research in this area. First, steady flow through an axial turbine is compared with full annular pulsed flow closely …
An Experimental Analysis Of The Weighted Sum Of Spatial Gradients Minimization Quantity In Active Structural Acoustic Control Of Vibrating Plates, Daniel R. Hendricks
An Experimental Analysis Of The Weighted Sum Of Spatial Gradients Minimization Quantity In Active Structural Acoustic Control Of Vibrating Plates, Daniel R. Hendricks
Theses and Dissertations
Active Structural Acoustic Control (ASAC) is a subcategory of the more widely known field of Active Noise control (ANC). ASAC is different from traditional ANC methods because it seeks to attenuate noise by altering the noise producing structure instead of altering the acoustic waves traveling through the air. The greatest challenge currently facing ASAC researchers is that a suitable parameter has not yet been discovered which can be easily implemented as the minimization quantity in the control algorithms. Many parameters have been tried but none effectively attenuate the sound radiation in a way that can be easily implemented. A new …
Computational And Experimental Study Of Degeneration, Damage And Failure In Biological Soft Tissues, Gregory Allen Von Forell
Computational And Experimental Study Of Degeneration, Damage And Failure In Biological Soft Tissues, Gregory Allen Von Forell
Theses and Dissertations
The purpose of this work was to analyze the biomechanics of degeneration, damage, and failure in biological soft tissues both experimentally and computationally to provide insight into tendon or ligament tearing, tendo-achilles lengthening and lumbar spine dysfunction. For soft tissue tearing, experimental studies for calculating fracture toughness were performed and determined that tendons and ligaments are able to completely resist tear propagation. For tendo-achilles lengthening, a damage model was developed to mimic the behavior of the lengthening that occurs as a result of the percutaneous triple hemisection technique. The model provided insight for predicting the amount of lengthening that occurs …
Active Structural Acoustic Control Of Clamped And Ribbed Plates, William Richard Johnson
Active Structural Acoustic Control Of Clamped And Ribbed Plates, William Richard Johnson
Theses and Dissertations
A control metric, the weighted sum of spatial gradients (WSSG), has been developed for use in active structural acoustic control (ASAC). Previous development of WSSG [1] showed that it was an effective control metric on simply supported plates, while being simpler to measure than other control metrics, such as volume velocity. The purpose of the current work is to demonstrate that the previous research can be generalized to plates with a wider variety of boundary conditions and on less ideal plates. Two classes of plates have been considered: clamped flat plates, and ribbed plates. On clamped flat plates an analytical …
The Effects Of Wrist Orthoses On The Stiffness Of Wrist Rotations, Daniel Brad Seegmiller
The Effects Of Wrist Orthoses On The Stiffness Of Wrist Rotations, Daniel Brad Seegmiller
Theses and Dissertations
Wrist orthoses are the most common upper limb orthoses, being used by thousands of individuals each year to stabilize, immobilize, or support the wrist joint. Wrist orthoses achieve their function by altering the stiffness of the wrist joint (Figure 1-1). However, there is no quantitative understanding of how wrist orthoses affect wrist stiffness, and consequently, wrist orthosis development often relies on feel, intuition, or empirical heuristics rather than a methodical, quantitative approach. Because wrist movement control is dominated by wrist joint stiffness (Charles and Hogan 2011) a quantitative understanding of how wrist orthoses alter the stiffness of the wrist is …
Burnout, No, Flame Temperature, And Radiant Intensity From Oxygen-Enriched Combustion Of A Hardwood Biomass, Joshua David Thornock
Burnout, No, Flame Temperature, And Radiant Intensity From Oxygen-Enriched Combustion Of A Hardwood Biomass, Joshua David Thornock
Theses and Dissertations
Increasing concern for energy sustainability has created motivation for the combustion of renewable, CO2 neutral fuels. Biomass co-firing with coal provides a means of utilizing the scaled efficiencies of coal with the lower supply availability of biomass. One of the challenges of co-firing is the burnout of biomass particles which are typically larger than coal but must be oxidized in the same residence time. Larger biomass particles also can increase the length of the radiative region and alter heat flux profiles. As a result, oxygen injection is being investigated as a means of improving biomass combustion performance.An Air Liquide designed …
Wax Pattern Shrinkage Project Summary, David Bishop, Perry Carter
Wax Pattern Shrinkage Project Summary, David Bishop, Perry Carter
Journal of Undergraduate Research
Purpose: The purpose of this project was to better understand the sources of variation that influence the shrinkage of wax patterns in investment casting. With a better understanding of the variation, manufacturers will be able to produce parts that have more precise dimensions.
Cad Tools For Thermal Growth Research, C. Porter Bassett, Dr. C. Greg Jensen
Cad Tools For Thermal Growth Research, C. Porter Bassett, Dr. C. Greg Jensen
Journal of Undergraduate Research
For my project I developed two tools to aid in manufacturing research that is currently being conducted in the Mechanical Engineering Department. This research is about milling, a type of manufacturing where metal is machined bye a spinning cutting tool, very similar to a drill bit, that cuts away the metal. This process generates a lot of heat and causes the cutting tool to heat up. When it heats up, it also expands and changes shape. The change in size of the cutting tool effects how much metal it removes. In precision work, this change in shape can be enough …
Strain In Polysilicon Microbeams: The Relationship Between Beam Geometry And The Nominal Strain At Failure, Susan Norma, Candland Bromley, Dr. Larry L. Howell
Strain In Polysilicon Microbeams: The Relationship Between Beam Geometry And The Nominal Strain At Failure, Susan Norma, Candland Bromley, Dr. Larry L. Howell
Journal of Undergraduate Research
The objective of this research was to investigate the stress and strain behavior of microscopic cantilevered polycrystallin silicon (polysilicon) beams. A knowledge of this behavior is necessary to accomplish reliable mechanical design of micro-electro-mechanical systems (MEMS).
Developing An Architecture Framework For Cloud-Based, Multi-User, Finite Element Pre-Processing, Jared Calvin Briggs
Developing An Architecture Framework For Cloud-Based, Multi-User, Finite Element Pre-Processing, Jared Calvin Briggs
Theses and Dissertations
This research proposes an architecture for a cloud-based, multi-user FEA pre-processing system, where multiple engineers can access and operate on the same model in a parallel environment. A prototype is discussed and tested, the results of which show that a multi-user preprocessor, where all computing is done on a central server that is hosted on a high performance system, provides significant benefits to the analysis team. These benefits include a shortened preprocessing time, and potentially higher-quality models.
An Investigation Into The Mechanisms Of Formation Of The Hard Zone In Fsw X65, Jacob D. Allred
An Investigation Into The Mechanisms Of Formation Of The Hard Zone In Fsw X65, Jacob D. Allred
Theses and Dissertations
Friction stir welding (FSW) of HSLA steel commonly produces a hard zone (HZ) on the advancing side (AS) of the weld. Despite its detrimental effects on weld toughness, the mechanisms of its formation have not been thoroughly investigated and are not well understood. This paper investigates the various mechanisms in FSW believed to affect the weld HZ, namely: strain, strain-rate, peak temperature and cooling rate. Gleeble tests indicate that strain and strain rate have negligible effects on weld HZ with cooling rate and peak temperature as dominant effects. Jominy tests resulted in cooling rate having 270% greater influence than peak …
Trajectory Generation And Optimization For Experimental Investigation Of Flapping Flight, Michael Schnebly Wilcox
Trajectory Generation And Optimization For Experimental Investigation Of Flapping Flight, Michael Schnebly Wilcox
Theses and Dissertations
Though still in relative infancy, the field of flapping flight has potential to have a far-reaching impact on human life. Nature presents a myriad of examples of successful uses of this locomotion. Human efforts in flapping flight have seen substantial improvement in recent times. Wing kinematics are a key aspect of this study. This study summarizes previous wing trajectory generators and presents a new trajectory generation method built upon previous methods. This includes a novel means of commanding unequal half-stroke durations subject to robotic trajectory continuity requirements. Additionally, previous optimization methods are improved upon. Experimental optimization is performed using the …
Optical Measurements Of Diesel Soot Formation, Michael Joseph Richards, Dr. Dale Tree
Optical Measurements Of Diesel Soot Formation, Michael Joseph Richards, Dr. Dale Tree
Journal of Undergraduate Research
The purpose of this project was to aid in the research of Kenth Svensson, PhD. student at BYU. I was able to perform many vital tasks in preparation for data acquisition. The proposal which we submitted named three tasks which were measuring and mapping the temperature gradient within a combustion chamber, mapping the mass of the fuel as a function of injection duration and pressure, and calibrating a CCD camera. A partial summary of Svensson’s research topic and objectives is provided below to help others understand the importance of this research.
Apparatus To Measure The Performance And Manufacturability Of The Multiple-Layer Floating-Opposing Arm Centrifugal Force Clutch, Derek Wright, Dr. Robert Todd
Apparatus To Measure The Performance And Manufacturability Of The Multiple-Layer Floating-Opposing Arm Centrifugal Force Clutch, Derek Wright, Dr. Robert Todd
Journal of Undergraduate Research
Centrifugal force clutches are used around the globe in devices from washing machines to garden tillers. Considering methods of reducing the cost of such clutches, the Utah Center of Excellence for Compliant Mechanism Research developed a fully compliant version, known as the Floating- Opposing Arm Centrifugal Force (FOA) Clutch. Unfortunately, the thickness required for the FOA clutch to perform competitively with comparable clutches makes manufacturing solid FOA clutches slow and costly. To overcome this difficulty, the clutch may be produced as stackable thin layers that sum to the desired performance characteristics. A testing apparatus is required to quantify the performance …
Comparison Of The Variance In The R-Value Calculated Using The Power Law In If Steel To Experimental Measurements, Craig Przybyla, Dr. Brent Adams
Comparison Of The Variance In The R-Value Calculated Using The Power Law In If Steel To Experimental Measurements, Craig Przybyla, Dr. Brent Adams
Journal of Undergraduate Research
As advances in engineering and technology increasingly require engineers and scientists to work in smaller length scales, they must have a greater understanding about how materials and their properties behave at these scales. This is true particularly in the field of mechanical engineering with the development of MicroElectroMechanical Systems or MEMS. These are tiny mechanical systems that are only measured in micrometers and that can only be seen with the aid of high powered microscopes. In order to build MEMS that are reliable and perform as they should, engineers not only must have an understanding of the material properties of …