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...
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...
Teamwork has become a popular operational strategy applied as part of workforce management plans in manufacturing and service industries. Teamwork has been commonly used in organizations to pursue different goals such as increase business operations agility, boost company productivity, improve quality in operations, increase company flexibility, promote collaborative learning, hasten...
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...
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...
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...
Moving mixed-model assembly lines are used by many companies to assemble multiple model types of a particular product. A moving assembly line consists of a material movement system that moves jobs at a constant velocity across a series of workstations. The variation in the work content of jobs at workstations...
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 myriad of problems facing the world today are increasingly complex, dynamic, and transcend multiple domains necessitating the need for an equally complex and trans-disciplinary approach to solve these problems. Systems thinking promises to provide the skills necessary for all citizens of the world, not just the experts, to handle...
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....
This study seeks to determine the effect of instructional design and emotional state on performance, considering interest and attention as mediators. To identify this effect, a Structural Equation Model (SEM) is applied to analyze individual performance based on five variables: information representation, emotional state, pupil size, alpha power, and task...
Manufacturing process design (MPD) represents a design-oriented approach to manufacturing engineering. In this dissertation, Haynes 230 (H230), a solid solution-strengthened Ni-based superalloy, was chosen to meet the material requirements of a microchannel solar receiver (MSR) needed to increase the efficiency and reduce the cost of solar thermal power generation. An...
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 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....
Specific energy, defined as the energy consumed by per unit volumetric removal rate, is one of the key metrics used for evaluating the environmental performance of a machining process. Grinding is a traditional machining process, characterized by high specific energy and poor environmental performance. Growing global concerns about climate change...
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...
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...