Mechanical Engineering Commons^™

Orbital Angular Momentum Transformation Of Optical Vortex With Aluminum Metasurfaces, Yuchao Zhang, Xiaodong Yang, Jie Gao

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The orbital angular momentum (OAM) transformation of optical vortex is realized upon using aluminum metasurfaces with phase distributions derived from the caustic theory. The generated OAM transformation beam has the well-defined Bessel-like patterns with multiple designed topological charges from -1 to +2.5 including both the integer-order and fractional-order optical vortices along the propagation. The detailed OAM transformation process is observed in terms of the variations of both beam intensity and phase profiles. The dynamic distributions of OAM mode density in the transformation are further analyzed to illustrate the conservation of the total OAM. The demonstration of transforming OAM states arbitrarily …

Spatial Variation Of Vector Vortex Beams With Plasmonic Metasurfaces, Yuchao Zhang, Jie Gao, Xiaodong Yang

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The spatial variation of vector vortex beams with arbitrary polarization states and orbital angular momentum (OAM) values along the beam propagation is demonstrated by using plasmonic metasurfaces with the initial geometric phase profiles determined from the caustic theory. The vector vortex beam is produced by the superposition of deflected right- and left-handed circularly polarized component vortices with different helical phase charges, which are simultaneously generated off-axially by the single metasurface. Besides, the detailed evolution processes of intensity profile, polarization distribution and OAM value along the beam propagation distance is analyzed. The demonstrated arbitrary space-variant vector vortex beam will pave the …

A Survey Of Mathematical Models Of Human Performance Using Power And Energy, Vijay Sarthy Mysore Sreedhara, Gregory M. Mocko, Randolph E. Hutchison

Publications

The ability to predict the systematic decrease of power during physical exertion gives valuable insights into health, performance, and injury. This review surveys the research of power-based models of fatigue and recovery within the area of human performance. Upon a thorough review of available literature, it is observed that the two-parameter critical power model is most popular due to its simplicity. This two-parameter model is a hyperbolic relationship between power and time with critical power as the power-asymptote and the curvature constant denoted by W′. Critical power (CP) is a theoretical power output that can be sustained indefinitely by …

Dynamic Pressure Sensing For The Flight Test Data System, Marc Y. Goupil

Master's Theses

This thesis describes the design, assembly, and test of the FTDS-K, a new device in the Boundary Layer Data System (BLDS) family of flight data acquisition systems. The FTDS-K provides high-frequency, high-gain data acquisition capability for up to two pressure sensors and an additional three low-frequency pressure sensors. Development of the FTDS-K was separated into a core module, specialized analog subsystem, and practical testing of the FTDS-K in a flow measurement mission. The core module combines an nRF52840-based microcontroller module, switching regulator, microSD card, real-time clock, temperature sensor, and trio of pressure sensors to provide the same capabilities as previous-generation …

Flight Test Data System For Strain Measurement, Zachary David Wilson

Master's Theses

This thesis describes the design and evaluation of two devices to be included in the next generation of the family of devices called the Boundary Layer Data System (BLDS). The first device, called the Quasi-Static Strain Data Acquisition System, is a continuation of the BLDS-M series of devices to be known as the Flight Test Data System (FTDS) that uses a modular approach to acquire non-flow, quasi-static mechanical strain measurements. Various breakout boards and development boards were used to synthesize the device, which were housed by a custom PCB board. The system is controlled by the Simblee^TM System on …

Advanced Techniques For Carbon Nanotube Templated Microfabrication, Jason Matthew Lund

Theses and Dissertations

Carbon nanotube templated microfabrication (CNT-M) is a term describing a grouping of processes where carbon nanotubes (CNTs) serve a structural role in the fabrication of a material or device. In its basic form, CNT-M is comprised of two steps: produce a template made from carbon nanotubes and infiltrate the porous template with an additional material. Vertically aligned carbon nanotube (VACNT) templates can be grown to heights ranging from microns to millimeters and lithographically patterned to a desired form. Deposition of an existing thin film material onto a CNT template will coat all template surfaces and can produce a near solid …

Thermoresponsive Switchable Solvents For Enhanced, Simultaneous Microalgae Oil Extraction Reaction For Biodiesel Production, Mukhtar Ahmed Ismail

Mechanical Engineering Theses

In this study, a thermo-responsive switchable solvent (TSS), with a tunable hydrophobicity by simply changing the temperature (between 25 to 45oC) was used for simultaneous lipids extraction from wet microalgae and biodiesel production. By manipulating the hydrophobicity of the solvent, the cell wall disruption, lipid extraction and transesterification, and product separation steps were all carried out in a single pot, while eliminating the need for the energy intensive and time-consuming drying step. To overcome the problems currently encountered by using conventional alkaline catalysts in the transesterification of lipids, immobilized enzyme has been used. The proposed TSS consisted of an ionic …

Cavopulmonary Support For Failing Fontan Patients: Computational And In Vitro Assessment, Masoud Farahmand

All Dissertations

Congenital heart defects are responsible for the mortality of approximately 300,000 newborn each year. One study in 2010 estimated that over 2 million patients were living with congenital heart defects in the United States. Congenital heart defects have the highest hospitalization cost among other birth defect categories. The damage on the U.S economy in 2013 was estimated $6.1 billion. The most complex and severe form of these defects results in single ventricle physiology. Fortunately, over the last 50 years, these patients have been able to survive into adulthood as a result of three stages of surgeries culminating with Fontan operation. …

Stainless-Steel Column For Robust High Temperature Microchip Gas Chromatography, Abhijit Ghosh, Austin R. Foster, Jacob C. Johnson, Carlos R. Vilorio, Luke T. Tolley, Brian D. Iverson, Aaron R. Hawkins, H. Dennis Tolley, Milton L. Lee

Faculty Publications

This paper reports the first results of a robust, high performance, stainless-steel microchip gas chromatography (GC) column that is capable of analyzing complex real world mixtures as well as operating at very high temperatures. Using a serpentine design, a 10 m column with an approximately semicircular cross section with a 52 µm hydraulic diameter (D_h) was produced in a 17 cm x 6.3 cm x 0.1 cm rectangular steel chip. The channels were produced using a multilayer chemical etch and diffusion bonding process, and metal nuts were brazed onto the inlet and outlet ports allowing for column interfacing …

Experimental Investigation Of Flow Pulsation Waveforms In Rectangular Mesochannels For High Heat Flux Electronics Cooling, Jaakko Mcevoy, Sajad Alimohammadi, Tim Persoons

Articles

The ever rising heat fluxes encountered in electronic devices present a challenging thermal engineering problem. Not only is heat transfer enhancement a goal but more recently control of the enhancement is desired, especially in large scale data facilities where the heated outlet coolant fluid may be of use. Flow pulsation is one of the most common active heat transfer enhancement methods studied across all heat sink sizes. While the effects of pulsation have been shown to increase heat transfer under certain conditions there is still disagreement upon its merit for practical applications, with the majority of previous research has been …

A Generalisable Bottom-Up Methodology For Deriving A Residential Stock Model From Large Empirical Databases, Ciara Ahern, Brian Norton

Articles

Specifying representative reference buildings as a prerequisite for calculating cost-optimal energy performance requirements for buildings and building elements. Appropriate characterisation is prerequisite data for an overall national building energy consumption model to produce valid outcomes. Energy Performance Certificates (EPCs) are issued in the EU, for dwellings whenever they are constructed, sold or leased. Where acquiring data for an EPC would be prohibitively costly, nationally applicable default-values are employed for the building envelope thermal transmittance coefficients. Significant levels of retrofits led to the default-values used now being higher than is typical in reality, leading to characterisations of reference dwellings based on …

Investigation Into The Thermodynamics And Kinetics Of The Binding Of Cu2+ And Pb2+ To Tis2 Nanoparticles Synthesized Using A Solvothermal Process, Jesus Cantu, John Valle, Kenneth Flores, Diego Gonzalez, Carolina Valdes, Jorge Lopez, Victoria Padilla, Mataz Alcoutlabi, Jason Parsons

Mechanical Engineering Faculty Publications

In the present study, titanium (IV) sulfide (TiS2) was synthesized and investigated for the removal of Cu2+ and Pb2+ ions from aqueous solutions. TiS2 nanoparticles synthesized through a solvothermal synthesis were characterized using x-ray diffraction (XRD) and scanning electron microscopy (SEM). The average particle size for the TiS2 material was determined to be 8.03 ± 0.98 nm from the diffraction pattern. Studies were performed to examine the effects of pH, temperature, time, and interfering ions on the binding of Cu2+ and Pb2+ to the TiS2. As well isotherm studies were performed to determine the binding capacity of TiS2 for both …

Integration Of Inboard Propulsion In Shock Mitigating Membrane Hull Technology, Korrey Rotkiske

Theses and Dissertations

Membrane Hull Technology is a strength based marine vessel design concept that seeks to utilize the in-plane properties of fiber reinforced composites to generate a lighter weight vessel with inherent shock mitigation benefits. MHT has been applied on several Naval crafts yet the design features of inboard propulsion systems have not been addressed. Inboard propulsion systems are a very common form of propulsion used in many types of marine vessels especially larger vessels. This thesis seeks to overcome the inboard engine mounting challenges of MHT which limits use of this technology in the marine industry. The fundamental design elements of …

Nanothermomechanical Logic Gates For Thermal Computing, Ahmed Hamed

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

Limited performance and reliability of electronic devices at extreme temperatures, intensive electromagnetic fields, and radiation found in space exploration missions (i.e., Venus & Jupiter planetary exploration, and heliophysics missions) and earth-based applications require the development of alternative computing technologies. Thermal computing, data processing based on heat instead of electricity, is proposed as a practical alternative and opens a new scientific area at the interface between thermal and computational sciences.

We successfully developed thermal AND, OR and NOT logic gates, achieved through the coupling between near-field thermal radiation and MEMS thermal actuation. In the process, we developed two novel non-linear thermal …

Magnetic Properties Of Nd–Fe–B Permanent Magnets Under Thermal Experimentation, Géraldine Houis

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

Neodymium-Iron-Boron (Nd-Fe-B) magnets were developed in the 1980s, and since then, they have appeared as a common component in many fields. From the industry to consumers or defense applications, from turbines, computers, cellphones to most audio systems, Nd-Fe-B magnets are present everywhere. But when Nd-Fe-B magnets are applied to the motors of electric vehicles and wind-turbine generators, their temperature rises, therefore Nd-Fe-B-Dy magnets are used. However, while the use of these magnets is common at low temperatures, their properties decrease dramatically with the increase of temperature. In this paper, the Nd-Fe-B-based samples used were prepared by using arc melting, melt …

Development And Characterization Of A Biopolymer Direct-Write Process For 3d Microvascular Structures Formation., Xiaoming Fan

Electronic Theses and Dissertations

Engineering of bulk tissues has been limited by the lack of nutrient and waste exchange in these tissues without an adjacent capillary network. To produce microvasculature, a scaffold must be produced that provides temporary mechanical support and stimulate endothelial cell adhesion, growth, and morphogenesis into a vessel. However, current well-established techniques for producing microvasculature, such as electrospinning, are limited since they lack both the precision to control fiber placement in three-dimensional space and the ability to create fiber networks with predefined diameters to replicate the physiological microvascular progression from arteriole to capillary to venule. Our group has developed a “Direct-write” …

Estimation Of The Fatigue Life Of Additively Manufactured Metallic Components Using Modified Strain Life Parameters Based On Surface Roughness, Peter Grohs

Masters Theses

In this study, a method is developed to estimate the effects of surface roughness on the fatigue life of additively manufactured titanium Ti6Al4V, aluminum 7075–T6, and steel 4340 alloys through modified strain life parameters using finite element analysis (FEA). This method is highly beneficial to the fatigue analysis of as-built additively manufactured metal components, which possess rough surfaces that reduce fatigue life significantly but are challenging to analyze directly using finite element simulation because of complex geometries, i.e., modeling an exact surface profile is arduous.

An effective stress concentration factor, incorporating roughness data, is defined to quantify their effects on …

Gearbox Baffle Optimization, Megan Arduin

Masters Theses

Current literature reveals there is limited consensus on the placement of baffles within a gearbox to reduce churning losses. Thus, there is a need for a process to identify baffle clearances that result in maximum and minimum churning losses. There are two types of baffles: axial and radial. While both axial and radial baffles cause reductions in churning losses to various degrees, the focus is on the effect of radial baffles. The effect of a board (rectangular plate) baffle location on the churning losses of a single gear gearbox are evaluated using computational fluid dynamics (CFD) implemented in Ansys. Several …

Exploring Convergence Of Snake Skin-Inspired Texture Designs And Additive Manufacturing For Mechanical Traction, Catherine Sue Tiner

Graduate Theses and Dissertations

This research focuses on the understanding, development, and additive manufacture of a 3D printed snake skin-inspired texture pattern. The design functionalities of snake skin were determined through the study of the snake species Python Regius otherwise known as the ball python. Each scale of a snake has hierarchical texture with hexagonal macro-patterns aligned on the ventral surface of the skin with overriding anisotropic micro textured patterns such as denticulations and fibrils. Using a laser-powder bed fusion (L-PBF) process, 420 stainless steel samples were 3D printed which closely resemble the above described directional texture of natural snake skin. This printed surface …

Semantic And Qualitative Physics-Based Formal Reasoning For Functional Decomposition In Mechanical Design, Xiaoyang Mao

Theses and Dissertations

Function modeling plays an essential role in academy design studies, yet a lack of acceptance in industry. A possible reason is that the designer must have well understand of the controlled vocabularies and grammars to utilize this method. The research presented in this dissertation is to fill this gap so that designers can use function-based design method without relevant knowledge. In graph-based function models, the function verbs and flow nouns are usually chosen from predefined vocabularies. The vocabulary class definitions, combined with function modeling grammars defined at various levels of formalism, enable function-based reasoning. However, the text written in plain …

Numerical Modeling Of Phase Transition In Shock Tube Problem, Man Minh Le

Theses and Dissertations

In this work, we developed a numerical model for phase transition in shock-tube problem. This work focused on simulating shock-tube problem and the numerical framework is based on a two-phase flow model. Our simulation tool is an in-house FORTRAN multiphase compressible flow solver, RocSDT [31]. Specifically, this involves the Euler equations along with the Stiffened Gas Equation of State (EOS), an interface of liquid-gas type, and the effects of heat and mass transfer due to phase transition. This thesis described the implementation and incorporation of a phase transition model into a system of five partial differential equation model and the …

Hydrodynamic Ram Analysis Of Bonded Composite Fuel Tanks, Teddy Sedalor

Theses and Dissertations

Military aircraft are tested against a variety of ballistics threats as part of their design to assess their vulnerability. One aspect of this approach/requirement is Hydrodynamic Ram testing which accounts for projectile impact into fuel tanks. Hydrodynamic Ram (HRAM), which occurs due to overpressure created in an enclosed fluid as a result of the transfer of energy and momentum from a penetrating projectile, can be quite destructive to the enclosing structure, which makes testing expensive. Therefore the need arises for numerical methods to supplement the testing and provide more test data than can be obtained directly from the article test. …

Numerical Simulations Of Comprehensive Hydrodynamic Performance Of Darpa Suboff Submarine, Kenshiro Takahashi

Theses and Dissertations

A numerical study of the DARPA SUBOFF model using computational fluid dynamics (CFD) has been presented for developing a CFD application procedure to compute the hydrodynamic performance of underwater vehicles, including submarines. Several configurations, such as bare hull, fairwater, sterns, and/or ringwing-appended hulls, were examined for the straight-ahead, steady translation and turning, and self-propelled conditions. A systematic study was conducted to ensure an adequate computational domain expansion and reasonable prism layer mesh properties for solutions independent of the parameters. The hydrodynamic forces exerted on the hull and the appendages were verified and validated in accordance with a published methodology under …

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

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

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. The …

Experimental Investigation Of N2o/O2 Mixtures As Volumetrically Efficient Oxidizers For Small Spacecraft Hybrid Propulsion Systems, Rob L. Stoddard

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A hybrid thruster system utilizes propellants in two different stages, traditionally a solid fuel and a gaseous or liquid oxidizer. Recently hybrid thrusters have become a popular topic of research due to the high demand of a ”green” replacement for hydrazine. Not only are hybrid thruster systems typically much safer than hydrazine, but they are also a low-cost system with a high reliability in performance. The Propulsion Research Laboratory (PRL) at Utah State University (USU) has developed a hybrid thruster system using 3-D printed acrylonitrile butadiene styrene (ABS) as the fuel and gaseous oxygen (GOX) as the oxidizer. This system …

The Flame Characteristics Of Diesel Fuel Blend With Kepuh (Sterculia Foetida) Biodiesel, Dani Hari Tunggal Prasetiyo, Nasrul Ilminnafik, Salahuddin Junus

Journal of Mechanical Engineering Science and Technology (JMEST)

Kepuh biodiesel fuel (sterculia foetida) is an alternative fuel that can be used to replace fossil fuel. Diesel fuel is performed to determine the laminar burning velocity and high flame by adding biodiesel kepuh volume of 10%, 20%, 30%. The purpose of this study was to study the effect of biodiesel and the effect of bunsen burners on the laminar burning velocity and flame height. Bunsen burner is made of copper and stainless steel. Testing of flame characteristics was carried out by heating the mixture of fuel and air at a temperature of 200°C. The purpose of heating the air …

Critical Solid Fraction Point Analysis: Case Study On Cement Mill Machine Diaphragm, Mochamad Achyarsyah, Poppy Puspitasari

Journal of Mechanical Engineering Science and Technology (JMEST)

During the solidification process, metal liquids turn into solid geometry units including the riser and gating system. The disruption in the liquid flow often causes shrinkage in the object. Critical Solid Fraction Point is a critical point where the continuous liquid supply turned solid and unable to pour to some sections. Simulation software can predict the critical solid fraction time of an object and the liquid supply behavior. The simulation helps the designer in the casting design. The application of low steel alloys in the cement industry, e.g., the Diaphragm, needs development to minimize the shrinkage. This research aimed to …

Characteristic Analysis Of Horizontal Axis Wind Turbine Using Airfoil Naca 4712, Bili Darnanto Susilo, Gaguk Jatisukamto, Nurkoyim Kustanto

Journal of Mechanical Engineering Science and Technology (JMEST)

Wind energy has been developed and used as a source of electrical energy by converting wind energy into electrical energy using a generator. There are some wind turbine parameters that important for wind turbines design and model, includes the size of the rotor radius, airfoil selection, chord length, and pitch angle. The study aims to characterize the performance of a horizontal axis wind turbine using computational methods. The methods used a design and simulation of NACA 4412 and NACA 4712 airfoil using QBlade software using wind conditions in the region of Pancer, Jember. Results show that the maximum Cl value …

The Effect Of Chlorophyll Concentration From Papaya Leaves On The Performance Of Dye-Sensitized Solar Cell, Dede Rizali, Heru Suryanto, Sukarni Sukarni

Journal of Mechanical Engineering Science and Technology (JMEST)

Dye-Sensitized Solar Cell (DSSC) is the third generation solar cell that has sandwich structure consisted of organic dye material and other components such as titanium dioxide (TiO2) semiconductor, electrolyte, and substrates (counter electrode and working electrode). The dye in the device was made from green plant chlorophyll such as papaya. This research aimed to find the influence of dye concentration from papaya leaves chlorophyll on the performance of DSCC. The discussion covered the output power (Pout), Fill Factor (FF), and efficiency (ɳ). The method in this research was explorative experimental with independent variables such as direct and indirect sunlight. The …

Synthesis And Applications Of Hematite Α-Fe2o3 : A Review, Muhamad Muhajir, Poppy Puspitasari, Jeefferie Abdul Razak

Journal of Mechanical Engineering Science and Technology (JMEST)

This article reviewed the hematite α-Fe2O3. It focuses on its material properties, nanostructures, synthesis techniques, and its numerous applications. Researchers prepared the hematite nanostructure using the synthesis methods such as hydrothermal, and, further, enhanced it by improving the techniques to accommodate the best performance for specific applications and to explore new applications of hematite in humidity sensing.