Engineering Commons^™

Numerical Simulation Of Enhancement In Co2 Sequestration With Various Water Production Schemes Under Multiple Well Scenarios, Li Chen

McKelvey School of Engineering Graduate Student Theses & Dissertations

CO₂ geological sequestration simultaneously combined with water production from deep saline aquifers can effectively address the challenge faced by the modern energy systems for reducing the CO₂ emissions and water intensity while providing reliable, affordable, and secure energy. However, little attention has been paid to date in the literature on determining the best CO₂ injection strategy for achieving both the optimal water production and the optimal CO₂ space storage capacity while maintaining operational safety. This research first establishes three injection-extraction scenarios based on the typical geological parameters of the Junggar Basin in China to analyze the …

Temperature Corrected Turbulence Models For High Speed Compressible Flows, Shuai Shuai

McKelvey School of Engineering Graduate Student Theses & Dissertations

No abstract provided.

Cfd Simulations Of Chemical Looping Combustion In A Packed Bed And A Bubbling Bed Fuel Reactor, Guanglei Ma

McKelvey School of Engineering Graduate Student Theses & Dissertations

Chemical-looping combustion (CLC) is a next generation combustion technology that has shown great promise in addressing the need for high-efficiency low-cost carbon capture from fossil fueled power plants to address the rising carbon emissions. Although there have been a number of experimental studies on CLC in recent years, CFD simulations have been limited in the literature on CLC. The development and confidence in high-fidelity simulations of the CLC process is a necessary step towards facilitating the transition from laboratory-scale experiments to deployment of this technology on an industrial scale. In this research, first the CFD simulations of a CLC packed …

Numerical Drag Prediction Of Nasa Common Research Models Using Different Turbulence Models, Pan Du

McKelvey School of Engineering Graduate Student Theses & Dissertations

The goal of this research is to perform 3D turbulence flow simulations to predict the drag of Wing-body-tail (WBT) and Wing-body-nacelle-Pylon (WBNP) aircraft configurations from NASA Common Research Models. These configurations are also part of the 4th and 6th AIAA Drag Prediction Workshops in which CFD modelers have participated worldwide. The computations are performed using CFD solver ANSYS FLUENT. The compressible Reynolds-Averaged Navier-Stokes (RANS) equations are solved using two turbulence models – the Spalart-Allmaras (SA) and SST k-ω. Drag polar and drag rise curves are obtained by performing computations at different angles of attack at a constant Mach number. Pressure …

Numerical Simulation Of Flows Past A Circular And A Square Cylinder At High Reynolds Number, And A Curved Plate In Transitional Flow, Ling Zhang

McKelvey School of Engineering Graduate Student Theses & Dissertations

Increasing the prediction accuracy and computational efficiency of turbulence models at high Reynolds number remains a challenging problem in Computational Fluid Dynamics (CFD). In this paper, several turbulence models are applied for numerical simulation of flow past a circular and a square cylinder at high Reynolds number. Wray-Agarwal (WA) turbulence model is a recently developed one-equation turbulence model derived from k-w closure. Comparisons are made among computational results from WA model, Spalart-Allmaras (SA) model, the shear stress transport SST k-w model and the standard Wilcox k-w model. For circular cylinder, the computations are performed for Reynolds numbers and and simulation …

Aerodynamics And Vortex Structures Of A Flapping Airfoil In Forward Flight In Proximity Of Ground, Hang Li

McKelvey School of Engineering Graduate Student Theses & Dissertations

The traditional flapping wing high lift mechanism research mainly focuses on the wing in unbounded flow. However, the real insect flight includes not only the unbounded flow field but also the near-surface flight. Therefore, research on near-surface flight can help reveal the high-lift mechanism of insect flight and should also be beneficial to the research on Micro-Air-Vehicles (MAV). In this thesis, the flow fields of an airfoil in hover and forward flight are simulated in the presence of ground by newly available function of “dynamic meshing” in ANSYS Fluent is employed. The characteristics of aerodynamics, pressure distribution, and vortex structure …

Preliminary Study Of Optimization Of Normal Pulse Voltammetry For Actinide Measurement In Molten Salt Electrorefiners Using Licl-Kcl-Ucl3-Mgcl2 As A Surrogate Salt, Chao Zhang, Devin Rappleye, Michael Simpson

Faculty Publications

Normal pulse voltammetry has been applied and optimized to develop correlations between diffusional current and concentration for UCl₃ and MgCl₂ in molten eutectic LiCl-KCl. This method was selected to mitigate working electrode area growth in concentrated molten salt mixtures in which a fairly wide potential range is needed to analyze all actinides. MgCl₂ has been selected as a surrogate for PuCl₃ based on similar standard reduction potential. Diffusional current plateaus were successfully attained by adjusting the step size to 0.03 V. Relaxation time of 15 seconds was found to be sufficient to recover after each pulse. …

Uncertainty Quantification And Propagation Of Errors Of The Lennard-Jones 12-6 Parameters For N-Alkanes, Richard A. Messerly, Thomas A. Knotts Iv, W Vincent Wilding

Faculty Publications

Molecular simulation has the ability to predict various physical properties that are difficult to obtain experimentally. For example, we implement molecular simulation to predict the critical constants (i.e., critical temperature, critical density, critical pressure, and critical compressibility factor) for large n-alkanes that thermally decompose experimentally (as large as C₄₈). Historically, molecular simulation has been viewed as a tool that is limited to providing qualitative insight. One key reason for this perceived weakness in molecular simulation is the difficulty to quantify the uncertainty in the results. This is because molecular simulations have many sources of uncertainty that propagate …

Real Time Learning Level Assessment Using Eye Tracking, Saurin S. Parikh, Hari Kalva

MODVIS Workshop

E-Learning is emerging as a convenient and effective learning tool. However, the challenge with eLearning is the lack of effective tools to assess levels of learning. Ability to predict difficult content in real time enables eLearning systems to dynamically provide supplementary content to meet learners’ needs. Recent developments have made possible low-cost eye trackers, which enables a new class of applications based on eye response. In comparison to past attempts using bio-metrics in learning assessments, with eye tracking, we can have access to the exact stimulus that is causing the response. A key aspect of the proposed approach is the …

A Time-Series Forecasting Model For Windhoek Rainfall, Namibia, Godfrey T. Pazvakawambwa

Andrews Research Conference

The objective of the study was to use time series forecasting techniques to model Windhoek rainfall based on secondary monthly data from 1891 to 2011. Descriptive summary statistics in the form of measures of centrality and dispersion, time series plots, and autocorrelation functions were generated using R time series statistical software. The Box Jenkin’s ARIMA modelling procedure (model identification, model estimation, model validation) was used to determine the best models for the data. Model diagnostics based on residual analysis were performed to assess the adequacy of the identified models. The final model was then used to forecast monthly rainfall for …

Modeling Accommodation Control Of The Human Eye: Chromatic Aberration And Color Opponency, Agostino Gibaldi, Steven A. Cholewiak, Marty S. Banks

MODVIS Workshop

Accommodation is the process by which the eye lens changes optical power to maintain a clear retinal image as the distance to the fixated object varies. Although luminance blur has long been considered the driving feature for accommodation, it is by definition unsigned (i.e., there is no difference between the defocus of an object closer or farther than the focus distance). Nonetheless, the visual system initially accommodates in the correct direction, implying that it exploits a cue with sign information. Here, we present a model of accommodation control based on such a cue: Longitudinal Chromatic Aberration (LCA). The model relies …

Color Algebras, Jeffrey B. Mulligan

MODVIS Workshop

No abstract provided.

Evaluating The Impacts Of Farmers’ Behaviors On A Hypothetical Agricultural Water Market Based On Double Auction, Erhu Du, Ximing Cai, Barbara Minsker

Daugherty Water for Food Global Institute: Faculty Publications

Agricultural water markets are considered effective instruments to mitigate the impacts of water scarcity and to increase crop production. However, previous studies have limited understanding of how farmers’ behaviors affect the performance of water markets. This study develops an agent-based model to explicitly incorporate farmers’ behaviors, namely irrigation behavior (represented by farmers’ sensitivity to soil water deficit k) and bidding behavior (represented by farmers’ rent seeking l and learning rate b), in a hypothetical water market based on a double auction. The model is applied to the Guadalupe River Basin in Texas to simulate a hypothetical agricultural water market under …

2017 Spring Engr333 Project Final Report (Section A), Devin Auld, Scott Bokach, Joshua Bronner, Alex Meador, Ryan Hoek, Robert Lanser, Matthew Lenko, Elliot Slenk, Brendan Biesboer, Kyle Mailhot, Nate Zylstra, Jonah Engel, Rich Floro, Björn Krebs, Ethan Postmus, Cameron Bell, Caleb Bieske, Chris Griffin, Bernice Portugal, Ryan Beezhold, Dillon Carhuff, Ian Mcclaskie, Jared Vanderklay, Rounak Chatterjee, Toby Dalla Santa, Jenny Haney, Joel Hoskins, Caleb Senyshyn

ENGR 333

The objective of ENGR-333-A was to develop a well-defined, bottom-up energy demand model for the energy consumption of the dormitories on Calvin College’s campus for each year of the past decade within an accuracy of ± 2%.

2017 Spring Engr333 Project Final Report (Section B), Daniel Dick, Nathan Swaim, Jonathan Sager, Ellen Reidy, Jordan Swets, Joel Van Dyke, Connor Macdonald, Josiah Markvluwer, Justin Rohlicek, John Lee, Zach Mouw, Daniel Wharton, Sam Hanover, Jay Noyola, Adam Christenson, Scott Stamper, Aaron Tucker, Bethany Waanders, Joel Schaefer, Maddie Collins, Matthew Cok, Philip Kim, Steve Vanden Berg

ENGR 333

The Physical Education Complex is located in the North-end of Calvin College’s campus, and supports many athletic, academic, event and recreational functions. Due to its heavy use, the complex contributes 20% of the College’s electricity consumption. Monetarily, this equated to electricity costs of about $385,000 last year. With these financial implications, the College is searching for ways to reduce the cost. While there is little to no room for electricity cost rate reductions, there is opportunity for improvement through the implementation of more efficient components. However, the sources of electricity demand are largely unknown. Our objective is to develop a …

Numerical Study Of The Aerodynamics Of Dlr-F6 Wing-Body In Unbounded Flow Field And In Ground Effect, Ning Deng

McKelvey School of Engineering Graduate Student Theses & Dissertations

The main focus of this thesis is on the simulation of flow past a three-dimensional wing-body configuration (DLR-F6) in ground effect; a complex 3D wing-body configuration in ground effect has never been analyzed in the aerodynamics literature to date. For the purpose of validation of the simulation approach, computations are performed for the DLR-F6 wing-body in unbounded flow and are compared with the experimental data. The commercial CFD solver ANSYS FLUENT is employed for computations. Compressible Reynolds-Averaged Navier-Stokes (RANS) equations in conjunction with Spalart-Allmaras (SA) and - Shear Stress Transport (SST) turbulence models are solved. The validated code is employed …

A Tunable, Three-Dimensional In Vitro Culture Model Of Growth Plate Cartilage Using Alginate Hydrogel Scaffolds, Alek G. Erickson, Taylor D. Laughlin, Sarah Romereim, Catherine Sargus-Patino, Angela K. Pannier, Andrew T. Dudley

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Defining the final size and geometry of engineered tissues through precise control of the scalar and vector components of tissue growth is a necessary benchmark for regenerative medicine, but it has proved to be a significant challenge for tissue engineers. The growth plate cartilage that promotes elongation of the long bones is a good model system for studying morphogenetic mechanisms because cartilage is composed of a single cell type, the chondrocyte; chondrocytes are readily maintained in culture; and growth trajectory is predominately in a single vector. In this cartilage, growth is generated via a differentiation program that is spatially and …

Heuristics From Statistics—Modeling The Behavior And Perception Of Non-Rigid Materials, Vivian C. Paulun, Roland W. Fleming

MODVIS Workshop

No abstract provided.

Modelling Grip Point Selection In Human Precision Grip, Guido Maiello, Lina Klein, Vivian C. Paulun, Roland W. Fleming

MODVIS Workshop

No abstract provided.

Design Of A Very High Efficiency Evaporatively Cooled Mini-Split Air Conditioner, Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

An in-house research project at the Florida Solar Energy Center in 2013 was conducted to evaluate the potential of an evaporatively cooled mini-split heat pump. The mini-split heat pump modified was a 1.5-ton Fujitsu model with 19.2 SEER and 10.0 HSPF energy efficiency ratings. Cooling capacity of the system is variable and ranges from 7,000 to 23,000 Btu/h.

We demonstrated that it is possible to improve the energy efficiency of the evaluated mini-split air conditioner by 21% seasonally in Florida's humid climate using an evaporative pre-cooler. Further, we showed the same apparatus was able to improve air conditioner efficiency by …

Investigating Read/Write Aggregation To Exploit Power Reduction Opportunities Using Dual Supply Voltages, Gu Yunfei

McKelvey School of Engineering Graduate Student Theses & Dissertations

Power consumption plays an important role in computer system design today. On-chip memory structures such as multi-level cache make up a significant proportion of total power consumption of CPU or Application-Specific Integrated Circuit (AISC) chip, especially for memory-intensive application, such as floating-point computation and machine learning algorithm. Therefore, there is a clear motivation to reduce power consumption of these memory structures that are mostly consisting of Static Random-Access Memory (SRAM) blocks. In this defense, I will present the framework of a novel dual-supply-voltage scheme that uses separate voltage levels for memory read and write operations. By quantitatively analyzing the cache …

Particle Enrichment In Longitudinal Standing Bulk Acoustic Wave Microfluidics, Mingyang Cui

McKelvey School of Engineering Graduate Student Theses & Dissertations

Separation, isolation, and enrichment of targeted nano- and microparticles are critical to a variety of biomedical applications from clinical research (development of therapeutics and diagnostics) to fundamental investigations that require concentration of specific cells from culture, separation of target species from heterogenous mixtures, or controlled perturbation of cells and microorganisms to determine their response to stimuli. Numerous techniques are available for bench-scale and medical settings; however, these traditional approaches are often labor intensive, time-consuming, costly, and/or require modification of the target. Efficiency and specificity are also lacking. Recently, techniques that exploit the similar scales of microfluidic technologies and the intrinsic …

Desulfination By 2′-Hydroxybiphenyl-2-Sulfinate Desulfinase Proceeds Via Electrophilic Aromatic Substitution By The Cysteine-27 Proton, Inacrist Geronimo, Shawn R. Nigam, Christina M. Payne

Chemical and Materials Engineering Faculty Publications

Biodesulfurization is an attractive option for enzymatically removing sulfur from the recalcitrant thiophenic derivatives that comprise the majority of organosulfur compounds remaining in hydrotreated petroleum products. Desulfurization in the bacteria Rhodococcus erythropolis follows a four-step pathway culminating in C–S bond cleavage in the 2′-hydroxybiphenyl-2-sulfinate (HBPS) intermediate to yield 2-hydroxybiphenyl and bisulfite. The reaction, catalyzed by 2′-hydroxybiphenyl-2-sulfinate desulfinase (DszB), is the rate-limiting step and also the least understood, as experimental evidence points to a mechanism unlike that of other desulfinases. On the basis of structural and biochemical evidence, two possible mechanisms have been proposed: nucleophilic addition and electrophilic aromatic substitution. Density …

Microstrip Diplexer With Low Channel-Frequency Ratio, Kirti Dhwaj, Li (Lijun) Jun Jiang, Tatsuo Itoh

Electrical and Computer Engineering Faculty Research & Creative Works

The paper presents a microstrip diplexer constructed by joining two stub-perturbed ring resonators at a T-junction. Each ring resonator acts as a bandpass filter with a transmission zero lying very close to the passband of the other filter, thereby increasing the isolation between the two channels. A short stub is additionally added at the T-junction to improve the matching at the common port. The diplexer is able to achieve a channel separation of 50 MHz, with the two channels centered at 2.49 GHz and 2.37 GHz respectively. This translates to a center frequency ratio of 1.05 between the two channels, …

Bendablesound: An Elastic Multisensory Surface Using Touch-Based Interactions To Assist Children With Severe Autism During Music Therapy, Franceli L. Cibrian, Oscar Peña, Deysi Ortega, Monica Tentori

Engineering Faculty Articles and Research

Neurological Music Therapy uses live music to improve the sensorimotor regulation of children with severe autism. However, they often lack musical training and their impairments limit their interactions with musical instruments. In this paper, we present our co-design work that led to the BendableSound prototype: an elastic multisensory surface encouraging users to practice coordination movements when touching a fabric to play sounds. We present the results of a formative study conducted with 18 teachers showing BendableSound was perceived as “usable” and “attractive”. Then, we present a deployment study with 24 children with severe autism showing BendableSound is “easy to use” …

Cache Power Optimization Using Multiple Voltage Supplies To Exploit Read/Write Asymmetry, Dengxue Yan

McKelvey School of Engineering Graduate Student Theses & Dissertations

Power consumption becomes more and more critical in computer systems nowadays. Most of the previous work has been focusing on general-purpose computational core, but optimization techniques for conventional CPU core has reached a limit. Our experimental results show that read operations in SRAM can be performed at a lower supply with much reduced power consumption compared to write operations. Based on this observation and the fact that cache, consisting mostly of SRAM, often occupies significant on-chip area of the CPU and consumes a huge portion of the CPU power, we propose a new method to reduce the power consumption of …

Flexible Plasmonic Sensing Substrates And Their Application In Explosive Sensing, Justin Bae, Srikanth Singamaneni

McKelvey School of Engineering Graduate Student Theses & Dissertations

With an increasing use of improvised explosive devices in combat and terrorism, there is an urgent need for novel methods of trace explosive detection that can provide an inexpensive and effective solution. This study focuses on the development of such platform using flexible surface enhanced Raman scattering (SERS) substrates. Gold nanorods(AuNR) functionalized with peptides selective to explosive molecules, trinitrotoluene(TNT) and dinitrotoluene (DNT) were immobilized on various substrates to fabricate a flexible SERS substrate. The peptide conjugated AuNRs can detect TNT and DNT vapors, and the cysteamine conjugated nanorods could detect TNT in aqueous solution down to 100 nM.

Additionally, we …

Computations Of Flow Fields Of An Airfoil And A Wing With Gurney Flap In Ground Effect, Xuan Zhang

McKelvey School of Engineering Graduate Student Theses & Dissertations

High lift devices used in transport aircraft are complex multi-element wings with slats and flaps which are difficult to design and they incur high manufacturing and maintenance costs. Taking all requirements into consideration, for light aircrafts using Gurney Flap may offer a low cost, low maintenance solution for improving the aerodynamic performance of aircraft during take-off and landing. Gurney Flap, first invented by Dan Gurney, is a small tab projecting from the trailing edge of airfoil. Gurney Flap can increase the lift coefficient and decrease the angle of attack for zero lift. However, at low angle of attack, Gurney flap …

Understanding Deleted File Decay On Removable Media Using Differential Analysis, James H. Jones Jr, Anurag Srivastava, Josh Mosier, Connor Anderson, Seth Buenafe

Annual ADFSL Conference on Digital Forensics, Security and Law

Digital content created by picture recording devices is often stored internally on the source device, on either embedded or removable media. Such storage media is typically limited in capacity and meant primarily for interim storage of the most recent image files, and these devices are frequently configured to delete older files as necessary to make room for new files. When investigations involve such devices and media, it is sometimes these older deleted files that would be of interest. It is an established fact that deleted file content may persist in part or in its entirety after deletion, and identifying the …

Current Understanding And Future Research Directions At The Onset Of The Next Century Of Sintering Science And Technology, Rajendra K. Bordia, Suk-Joong L. Kang, Eugene A. Olevsky

Publications

Sintering and accompanying microstructural evolution is inarguably the most important step in the processing of ceramics and hard metals. In this process, an ensemble of particles is converted into a coherent object of controlled density and microstructure at an elevated temperature (but below the melting point) due to the thermodynamic tendency of the particle system to decrease its total surface and interfacial energy. Building on a long development history as a major technological process, sintering remains among the most viable methods of fabricating novel ceramics, including high surface area structures, nanopowder-based systems, and tailored structural and functional materials. Developing new …