Implementing multicomponent diffusion in numerical combustion studies is computationally expensive due to the challenges involved in computing diffusion coefficients. As a result, mixture-averaged diffusion treatments or simpler methods are used to avoid these costs. However, the accuracy and appropriateness of the mixture-averaged diffusion model has not been verified for three-dimensional...
Heat flux measurements of radiation emissions from turbulent premixed flames diluted with N 2 and CO 2 were taken to identify sensitivities of radiation heat loss to diluent fraction and species. This work is motivated by the desire to better characterise radiant heat transfer in the presence of combustion products,...
Digital Human Modeling (DHM) is a computational design tool that allows designers to use virtual prototypes of design for exploring ergonomics requirements. DHM brings in the advantage of reducing the time and finances committed to building the physical prototypes as well as minimizing the efforts put on performing human subject...
Topology optimization (TO) is a mathematical method to find the optimal size, shape and connectivity of a domain under specified conditions, and has had many applications in engineering design. However, challenges remain in realizing TO as an effective design tool for many design situations. Uncertainty is ubiquitous in nature and...
This dissertation details the application of digital image correlation (DIC) in novel methods for mechanical testing and shape characterization. The first usage manifested in the development of a novel composite test specimen that provided the ability to characterize the matrix compression energy release rate at initiation and subsequent crack propagation....
The behavior of the thin liquid film formed between a bubble and hydrophobic membrane is of high interest in applications where separating two-phase mixtures is beneficial. One such application is in-situ vapor extraction heat sinks. In these systems, high heat transfer rates are accomplished by taking advantage of the high...
The orb web is a multipurpose structure---serving as a home for its inhabitant spider, as a prey capture device, and as a physical extension of the spider’s sensing abilities. Biologists are particularly interested in the spider’s ability to locate prey trapped in its web by sensing the vibrations induced from...
The rising global trend to reduce dependence on fossil fuels has provided significant motivation toward the development of alternative energy conversion methods and new technologies to improve their efficiency. Recently, oscillating energy harvesters have shown promise as highly efficient and scalable turbines, which can be implemented in areas where traditional...
Microchannel high temperature recuperators have the advantage of higher heat transfer coefficients and lower size and weight than traditional high temperature recuperators. However, the industrial application of microchannel recuperators are restricted by the high cost of photochemical machining and diffusion bonding. The objective of this paper is to introduce a...
In order to solve some classic problems in traditional topology optimization, such as unknown material distribution, checker-boarding and curse of dimensionality, this thesis introduces a new method to construct a mechanical structure that can reduce mass and increase stiffness. It uses a graph to represent the skeleton of a structure....
The SpiderHarp is a bio-inspired electronic musical instrument that uses a localization algorithm developed at Oregon State University to translate plucks of its strings into musical notes. This localization algorithm was inspired by the way spiders locate prey in their webs. The SpiderHarp frame, sensors, and web design are also...
This thesis presents accurate and time-optimal smooth reference trajectory generation techniques for manufacturing equipment such as high-speed machine tools (MT) and industrial robots (IR). Typical machining tool-paths for MTs and IRs are defined as a series of discrete linear moves. Although Point-to-Point (P2P) feed motion can be generated by interpolating...
The aviation industry is pushing for better fuels and gas turbine engines for several reasons: cost, emissions, and to a lesser extent high-altitude relights. One aspect that research has been focused on to help reduce costs, emissions and better understand high-altitude relights is studying the combustion behavior of the fuel...
Controllers for robotic systems can be complex and difficult to write by hand. Learning offers an approach to improve a controller through direct feedback. Learning is not trivial, as the feedback does not tell the agent how to improve, only how well its current actions solve the given task. Learning...
To investigate the melting stage of indirect freeze desalination three numerical models were developed. A zeroth, first, and second order analyses modeled the melting of ice around the outside of a pipe as a function of time. The zeroth order analysis assumes the system to be steady state. The first...
Breakthroughs in heat sink design are now limited by conventional manufacturing techniques which can only produce basic fin shapes with homogenous surface structuring. Additive Manufacturing (AM) is a potential disruptive technology for heat sink design and other convective heat transfer solutions, as surface properties can be directionally varied to maximize...
Modern product development is a complex combination of multidisciplinary processes ranging from market research to design, engineering analysis, and logistics. The product development process has a significant impact on the success or failure of new product launches. The majority of consumer product launches fail, resulting in significant sunk cost in...
The leading edge of a sub-orbital, sounding rocket dictates an aerodynamically optimal profile which is difficult to manufacture. The university level offers no current standard to produce rocket nose cones made with pre-impregnated composites. Of particular interest is the molding technique used to fabricate a nose cone. The focus of...
This research presents a methodology to identify and analyze human-system interactions, and their potential failure modes using a functional decomposition approach during the early system design stage.
The fundamental research contribution of this work is the development of a framework to identify associations between physical user-product interactions, generic human errors...
In a seminal paper published in 1982, scientist have warned that humanity was pushing earth’s ecosystems beyond their capacities to support the web of life. One response to the concern was outlined by NASA with its vision for advanced fixed wing transport aircraft to be environmentally compatible and have revolutionary...
The fuzzy front end of engineering design can present a difficult challenge, and as such, recent engineering design research has focused on guiding and influencing the way a designer ideates. Early ideation can be especially difficult when attempting to integrate specific design objectives in product design, called Design for X...
Unmanned Aerial System (UAS) technology is a rapidly developing technological marketspace. This thesis focuses on micro, tethered, coaxial UASs and the development of an electrically-tethered observation platform (ETOP). The thesis details the current status of the technology as well as current products on the market. Stability considerations, critical when adding...
Legged robots, while advancing quickly, have far to go before they can recover from major disturbances safely and consistently. Reflected inertia, which affects how quickly the actuators can physically respond to an environmental disturbance, and delay, which describes the time necessary for the controller to sense, re-plan, and respond to...
As CAD tools become more sophisticated, engineers are able to more easily create complex part geometries with minimal mass given strength and stiffness requirements. However, these complex part geometries can be difficult to subtractively manufacture, which consequently increases manufacturing cost and production time. This thesis presents a method independent of...
For the 2019 season, a new chassis layup was designed that is much stronger than in previous years, yet only slightly heavier. Compared to the baseline steel tube frame, the 2019 chassis has safety factors of about 110% for most zones. Also, a new impact attenuator was designed that absorbs...
With the widespread replacement of aluminum with composite materials, particularly in aircraft structures, the lack of comprehensive understanding of these materials is unsettling. The complex nature of these materials, with respect to isotropic aluminum, makes the prediction of their mechanical response equally complex. The failure of carbon fiber reinforced plastic...
Clean cooking technologies and fuels have been cited as a viable way to slow climate change and reduce the health and environmental impacts associated with traditional cooking devices used by 40% of the world. While engineers in the Design for Development sector have created hundreds of stove designs that perform...
Clean technologies can address multiple challenges associated with climate change, environmental protection, and human health. However, the impact desired by introduction of such technologies is achievable only if new options effectively replace inefficient, conventional practices. This ‘design for adoption’ requires understanding of user motivations, associated beliefs, context of use, and...
Selective laser melting (SLM) is an additive manufacturing (AM) process that uses a laser beam to melt metal powder as it is spread onto the build surface using a roller or scraper, followed by rapid solidification to manufacture a 3D component, one layer at a time.
In SLM process, density...
The unsustainable use of fresh water sources and unavailability of fresh water in certain parts of the world have created a demand for water desalination systems. Desalination methods are effective at producing consumable water, but often require large scale setups, high energy consumption, and careful maintenance. A team of students...
This work develops the Global Formula Racing computational fluid dynamics (CFD) model in StarCCM+ to allow for vehicle attitude studies to be ran to evaluate Formula Student (FS) vehicle aerodynamic loads. Attitudes that this model allows to be studied include roll, pitch, yaw, heave, tire angle, and vehicle speed. The...
The current knowledge on the microstructural evolutions and mechanical properties of selective laser melting (SLM) produced H13 tool steel components is limited. This research is focused on optimization of SLM processing parameters for H13 tool steel and investigation of microstructure and mechanical properties of H13 tool steel components after SLM...
The purpose of this report is to detail the design and validation of a prototype robot that feeds biomass into a range of small household cookstoves at a programmable rate. Improved design and testing methods for the development of improved biomass cookstoves are needed to design stoves that alleviate the...
Freeze desalination poses as a potential solution to many of the issues that accompany current desalination methods. The research detailed in this manuscript involves creating and analyzing a numerical model of the freezing operation of an indirect contact freeze-melting (FM) desalination system. In this initial analysis, pure water is frozen...
Energy from offshore wind could provide substantial power generation if further utilized. One area of significant research focus is in developing floating offshore wind devices, which would allow for wind energy to be gathered in deep water where driven monopile turbines are infeasible. However, floating offshore wind is not currently...
Marching band activities consist of both physically and cognitively demanding tasks. The demands that this activity has on players has largely been unstudied. The goal of this study was to investigate the effects of players’ experience level, role, and gender on the workload of marching band players via a field...
Vortical structures are the driving mechanism of transition to turbulence in porous media requiring adequately resolved observations along with analysis of the scale and energy of flow within the pores. Of specific interest is to understand the vortex dynamics, energy, and turbulent mixing and transport properties in the scale of...
As carbon emissions are negatively impacting ecosystems across the globe, researchers are in a race against time to provide cleaner and more eÿcient power. Detonation engines can help meet the increasing demands for cleaner and more eÿcient power generation by providing an alternative means to use oxy-fuel combustion for carbon...
Gasoline direct injection engines, with downsized boosted technology, present a promising option for enhancing power density and reducing fuel consumption for next-generation engine designs to meet stringent fuel economy and emission standards. However, these developments in the low-speed and high-load operating regime are challenged by the occurrence of a new...
Spot fires caused by lofted embers (i.e., firebrands) can be a significant factor in the spread of wildland fires. Embers can be especially dangerous near the wildland-urban interface (WUI) because of the potential for the fire to be spread near or on structures. Many studies have investigated the transport of...
Improving the coexistence of eagles and wind energy is a critical effort for the sustainable expansion of the wind energy sector. Information about eagle activity and interactions with wind turbines enables verification of deterrence methods. This information can be broken into two categories: eagle activity in the airspace around wind...
Force data for a flapping foil energy harvester with active leading edge motion operating in the low reduced frequency range is collected to determine how leading edge motion affects energy harvesting performance. The foil pivots about the midchord and operates in the low reduced frequency range of 0.06, 0.08, and...
Airborne Wind Energy System (AWES) are quickly coming to fruition, with increased energy production while reducing the cost of implementation and materials. This thesis develops a new computational model for a tethered AWES and characterizes a new rapid prototyping method with the objective of supporting the design and rapid prototyping...
Porous media are the materials containing void space or pores, where fluids and gases can pass through. Unsteady flows in porous media are encountered in many engineering applications and natural problems, such as CO₂ sequestration, high temperature nuclear reactor cooling, high efficiency combustion, chemical reactors, noise reduction on airplane trailing...
In order to enable better visualization and understanding of the effect of the robot's geometry and inertia on the robot's trajectories, this dissertation proposes to use geometric mechanics to bridge the gap between the physical motion of a robot and its mathematical structure. The main focus of this research is...
Single Point Incremental Forming (SPIF) is a forming process in which a fully clamped sheet is formed by a hemispherical ended tool that moves along a predefined 3D toolpath. The sheet is formed in a series of local deformations to reach its desired shape. Double Sided Incremental Forming (DSIF) includes...
This research seeks to identify how changes in temperature and oxygen concentration in the reaction zone affects liftoff heights for moderate or intense low-oxygen dilution (MILD) combustion of a jet fuel and a surrogate fuel. MILD combustion offers a method of burning fuels with reduced CO and NOx production by...
The Oregon State University (OSU) Experimental Sounding Rocket Association (ESRA) 30k Rocket Team is a student run rocket team that competes in the Intercollegiate Rocket Engineering Competition at Spaceport America. The goal of the competition is to launch a student designed, manufactured, and tested experimental sounding rocket to 30,000 ft...
Prediction and mitigation of chatter vibrations in machining operations and optimizing overall machining mechanics are crucial for achieving greater productivity and manufacturing efficiency. This thesis first explores effect of directional relationships on chatter stability in milling process. Based on the directional relationships, a geometry-based chatter stability index (CSI) is proposed...
Recent advancements in joining operations and additive manufacturing now allow complex metal parts to be built up from raw materials, as opposed to being machined down from solid blocks. This not only opens up the design space, but also allows for much more efficient manufacturing. By decomposing a complex part...
Due to global warming wildland fires are increasing in frequency and severity. In the case of wildland fires, the major modes of combustion occur include smoldering combustion and flaming combustion. Smoldering combustion occurs most commonly in porous fuels like peat, forest duff, and woody fuels, which are available in abundance...
This work explores a framework for the gathering and analysis of information rich customer needs, with the goal of informing inclusive product design practice. The goal is to be able to provide information and experience to designers so that they can better understand the needs of exceptional users and include...
As manufacturing advancements continue to develop, designers must be able to consider these technologies during the design process. Unfortunately, many of these new technologies, such as additive and advanced joining, have many nuances that require expert knowledge to effectively apply. Additionally, new design techniques, such as topology optimization, allow users...
This dissertation focuses on defining underlying mechanisms to enable the bio-inspired design of aerodynamic and/or hydrodynamic vehicles that operate within complex environments. This dissertation introduces four overarching research gaps found in current bio-inspired design research and four corresponding approach questions that guide the framework of the presented research. This research...
As a way to improve safety and economics, one area of research and commercialization of new nuclear power plants has focused on the development of small modular reactors (SMRs). NuScale Power has developed a 50 MWe natural convection cooling SMR coupled with a regenerative Rankine cycle. Current estimates place the...
Chain saws are a common tool used by large logging corporations and family homesteads to manage forests, limb trees and buck lumber. A significant cost of operation is the continuous required supply of bar and chain oil. Consumers and logging corporations desire a lubricant with a high performance to cost...
Simulations of combustion and reacting flows often encounter stiffness in the equations governing chemical kinetics. Explicit solvers for these ordinary differential equations offer low computational expense, but typically cannot efficiently handle stiff systems. In contrast, implicit methods demand greater expense but offer unconditional stability—as a result, most reactive-flow solvers rely...
The creation of autonomous decision makers to handle potentially hazardous or logistically complicated tasks is desirable for the purpose of reducing human labor and exposure to risk, and for increasing the general performance of autonomous systems in a wide variety of environments. However, traditional autonomous decision makers perform poorly when...
This work introduces a new methodology to design transportation fuels offering improved efficiency and reduced emissions, aimed to complement both traditional and emerging engine technologies. Many of these emerging technologies are centered around exploiting low temperature combustion (LTC) strategies that offer improved efficiency and reduced emissions. However, a standardized fuel...
The Formula Student Team Global Formula Racing from Oregon State University implemented an air suspension system in their 2017 combustion powered vehicle, mainly to save weight. This thesis covers the performance evaluation of such system by comparison to conventional coil over shocks. Utilizing two different Formula Student style courses, three...
Education as a right has taken off internationally with expanded national policies in recent years. Across Africa over 80% of countries have abolished tuition fees for primary education and several have made the leap to free secondary education as well. With decreased financial barriers keeping kids out of the classroom,...
Wind energy plays an important and growing role in the US energy profile. While other countries have expanded their wind industries into offshore development, large investment costs have hindered progress in the US offshore market despite the larger and more consistent resource available offshore. In this research, I explore the...
Modern scientific and engineering problems often require simulations with a level of resolution difficult to achieve in reasonable amounts of time—even in effectively parallelized programs. Therefore, applications that exploit high performance computing (HPC) systems have become invaluable in academia and industry over the past two decades. Addressing the questions that...
Condensers are vital components of power plants and are often one of the most major cost concerns when planning construction. Generally speaking, the surface area required to dissipate the heat generated in the boiler is so great that enormous and expensive structures are necessary. The usage of a hybrid surface...
The global water crisis is defined as one of the major threats facing humankind over the next decade with over 1 in 10 people lacking access to clean drinking water worldwide. An estimated 1.2 million people pasteurize their drinking water by using boiling as an indicator. Pasteurization is the process...
Microfluidics is an evolving field that focuses on the manipulation of small fluid volumes. Because of its micron-sized features, it is the basis for many lab-on-chip and point-of-care diagnostic devices. The devices are predominantly molded from polydimethylsiloxane (PDMS); however, production is a multi-hour or multi-day process that typically requires clean...
Complex engineered systems design is a collaborative activity. To design a system, experts from the relevant disciplines must work together to create the best overall system from their individual components. This situation is analogous to a multiagent system in which agents solve individual parts of a larger problem. Current multiagent...
Modern walking robots have shown that dynamic gaits can be achieved without ankle motors. It seems logical that the additional control authority that they provide can be used to improve the stability of the walking gait against foot placement errors caused by low level control. This thesis develops and compares...
Membrane based heat pumps systems have attracted the attention of many research groups as a potentially more environmentally friendly alternative to vapor compression systems that are being used for space cooling in 90\% of the buildings in the United States. Several prototypes systems have been developed, with reported claims of...
Improved cookstoves have been designed and disseminated for several decades in an effort to address the human health and environmental issues caused by the inefficient, traditional biomass cooking and heating methods used by 40% of the world’s people. Engineers and designers working on these improved stoves have tended to focus...
Using repositories to store product design information can provide additional and extensive design knowledge to the global design community. Using repository data in the design of new products can be especially impactful for DfX design objectives, such as product sustainability, about which many engineering designers have limited knowledge. Furthermore, repositories...
Wave Energy Converters (WEC) have great potential to help meet global energy demands, but even a single device can be challenging to model. Although most WEC concepts are modelled, many have been simplified with assumptions that do not accurately capture the true dynamics of the system. For this reason, data-driven...
A significant source of energy consumption comes from maintaining desired indoor environment conditions in warehouses and other industrial facilities. In efforts to combat the raising energy costs, studies into more efficient heating and cooling strategies has been a topic of consideration for a number of years. One of the areas...
Powder Bed Fusion (PBF) techniques are additive manufacturing (AM) technologies with paradigm-shifting potential for the production industry. However, before they can become viable production solutions for quality critical industries, issues with process consistency and repeatability need to be addressed. There is a need for in-situ sensing systems that characterize process...
As robotic systems become increasingly prevalent in our lives (e.g., by harvesting food, assisting with disaster response and defense, and transporting persons and our goods around the world) there is a growing need to ensure that they can cooperate to achieve their intended goals. Robotic cooperation in the real-world is...
As the trend of increasing age, weight, size, and disability within the population continues to increase, the demand for accessible transportation is expected to increase as well. Accessible and inclusive transportation is key in providing independent, barrier-free mobility for persons with accessibility needs. This thesis describes work completed in partial...
Repurposing internal combustion engines as petrochemical reactors (i.e., Reactor engines) could offer a smaller, scalable alternative to traditional full scale chemical processing facilities. For many chemical processes, incorporating catalyst particles in fluidized beds is expected to result in superior performance over both monoliths and packed beds. Conversion of ethane into...
This thesis uses the manuscript option. The First Manuscript proposed a markerless Motion Capture (MOCAP) system with a Virtual Reality (VR) setup, which has the potential to eliminate excess cost and time associated with physical prototyping. Validation of the proposed virtual ergonomics analysis was made by measuring L4/L5 compression forces....
Considering human product interactions early and often in the engineering design process may improve product quality, facilitate user safety, reduce time to market, decrease or eliminate the need for costly physical prototypes, and reduce expensive late stage design changes. Currently, F1 race cars do not include a cockpit canopy to...
An Achilles tendon injury can be devastating. Surgical methods to bring the muscle to full strength are not always available. Proposed is an ankle foot orthosis (AFO) that is entirely passive (does not add energy to the system) and uses the mechanical advantages provided by the walking gait of a...
Realizing the vast amount of energy available in ocean waves, an industry has emerged that is progressing towards the deployment of grid–connected wave energy converters. Likely to be deployed in arrays, a challenge to the wave energy industry is maximizing the energy production of such arrays. We have been developing...
Timber harvesters are high powered industrial grade rigs used to fell, delimb, and cut to size large trees. Hydraulic motors power sprockets that drive chains around a guide bar that get extended through logs during cuts. As technological advances allow for higher speeds a phenomenon called “chain shot” has...
There are many uncertainties that complex engineered systems will face throughout their lifecycles due to changes in internal and external conditions. It is desirable for complex engineered systems to be resilient against various uncertainties. The ability to overcome such uncertainties should be embedded into the system from the beginning. However,...
Adhesive use is becoming increasingly common in manufacturing processes. The advantage of adhesives are light weight components, non-destructive fastening techniques and distribution of loads over the applied bond region. Modeling the behavior of adhesive bond lines in fastening joints can help in the design process to make an optimized joint,...
This work presents a novel optimal control strategy for precision motion control of flexible ball-screw feed drives. Typically, ball-screw feed drive control relies on state feedback taken both from motor and the load sides. The controller designed in this thesis is based on the non-collocated framework, where all the feedback...
The competitiveness level of Formula Student is consistently increasing. Teams must allocate resources to develop new innovative designs to gain a competitive edge. Managing team resources effectively is critical to a team’s success. Reducing the resources required to manufacture specific components can be used to allocate resources to other beneficial...
Successfully predicting an accurate estimated cost is important in the assembly planning process. When designing an assembly plan, an accurate estimation ensures that the proposed plan can be achieved within the predetermined budget. However, achieving an accurate prediction is a challenge since it requires professional judgment, which is dependent upon...
The advancement of new manufacturing techniques such as additive manufacturing enable significantly greater freedom of design compared to conventional techniques. Of significant interest is what improvements could be made in the design of cold plates and heat sinks for electronics cooling. Greater design freedom could potentially enable new designs that...
Large amounts of energy are wasted when conditioned air in buildings is exhausted to meet ventilation requirements. There are several technologies to recover some of this energy, including the recent development of membrane based energy recovery ventilators (ERVs). ERVs exchange sensible heat and moisture between incoming fresh and outgoing exhaust...
This work is a culmination of a series of published works related to the use of the Material Point Method (MPM) in modeling wood adhesive bonds. The use of wood as construction material has the potential to play a small role in the solution to the current CO2 and climate...
Traditional electronic systems are usually fabricated via printed circuit boards (PCBs). In a regular PCB, the electronic components are placed and mounted on a two-dimensional board. Such a component layout limits the freedom in the component placement process which results in larger electronic devices. With the use of Additive Manufacturing...
Traditional electronic systems are usually fabricated via printed circuit boards (PCBs). In a regular PCB, the electronic components are placed and mounted on a two-dimensional board. Such a component layout limits the freedom in the component placement process which results in larger electronic devices. With the use of Additive Manufacturing...
Offshore renewable energy (ORE) has the potential to be a significant source of future global electricity production, reduce carbon emissions, decrease dependence on energy importation, and stimulate economic growth in coastal and remote areas. The availability and abundance of ORE, paired with growing coastal population centers, position offshore wind, wave,...
This thesis uses the manuscript option, and consists of a previously-published paper and a paper that has been accepted for publication. Manuscript One details an independent confirmatory study to Choo et al. (2014), which demonstrated that correlations exist between personality type and the outcome of concept ideation methods. This is...
Sintering of nanoparticles to create films and patterns of functional materials is emerging as a key manufacturing process in applications like flexible electronics, solar cells and thin-film devices. Further, there is the emerging potential to use nanoparticle sintering to perform additive manufacturing as well. While the effect of nanoparticle size...
There is growing commercial interest in the use of unmanned aerial vehicles (UAVs) in urban environments, specifically for package delivery applications. However, the size, complexity and sheer numbers of expected UAVs makes conventional air traffic management that relies on human air traffic controllers infeasible. To enable UAVs to safely and...
This research presents a methodology to analyze customer needs and direct the gathering of customer needs that both span the need space and are independent. An ontological categorization, the fundamental research contribution of this work, is created to support both aims of the overall methodology. Providing designers with a customer...
A common problem in energy allocation problems is managing the trade-off between selling surplus energy to maximize short term revenue, versus holding surplus energy to hedge against future shortfalls. For energy allocation problems, this surplus represents resource flexibility and is quantified as the surplus energy after meeting the demand. The...
Metal organic Frameworks (MOFs) that experience stimuli induced structural transformation could enable a whole new class of materials with remarkable properties. Photoactuating moieties in the structure could effect changes in the pore space or macroscale shape change enabling light driven gas separation and actuators. Here, we present a novel approach...
Renewable energy sources are becoming increasingly important due to their low environmental impact and limitless nature. This thesis explores the design of a 250 mW permanent magnet linear generator wave energy converter to power ocean sensors. While many wave energy converters exist, this is a unique application because the wave...