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Free And Open Source 3-D Model Customizer For Websites To Democratize Design With Openscad, Yuenyong Nilsiam, Joshua M. Pearce Mar 2018

Free And Open Source 3-D Model Customizer For Websites To Democratize Design With Openscad, Yuenyong Nilsiam, Joshua M. Pearce

Joshua M. Pearce

3-D printing has entered the consumer market because of recent radical price declines. Consumers can save substantial money by offsetting purchases with DIY pre-designed 3-D printed products. However, even more value can be obtained with distributed manufacturing using mass customization. Unfortunately, the average consumer is not technically sophisticated enough to easily design their own products. One solution to this is the use of an overlay on OpenSCAD parametric code, although current solutions force users to relinquish all rights to their own designs. There is thus a substantial need in the open source design community for a libre 3-D model customizer, …


Energy Payback Time Of A Solar Photovoltaic Powered Waste Plastic Recyclebot System, Shan Zhong, Pratiksha Rakhe, Joshua M. Pearce Mar 2018

Energy Payback Time Of A Solar Photovoltaic Powered Waste Plastic Recyclebot System, Shan Zhong, Pratiksha Rakhe, Joshua M. Pearce

Joshua M. Pearce

The growth of both plastic consumption and prosumer 3-D printing are driving an interest in producing 3-D printer filaments from waste plastic. This study quantifies the embodied energy of a vertical DC solar photovoltaic (PV) powered recyclebot based on life cycle energy analysis and compares it to horizontal AC recyclebots, conventional recycling, and the production of a virgin 3-D printer filament. The energy payback time (EPBT) is calculated using the embodied energy of the materials making up the recyclebot itself and is found to be about five days for the extrusion of a poly lactic acid (PLA) filament or 2.5 …


Open Source Multi-Head 3d Printer For Polymer-Metal Composite Component Manufacturing, J. Laureto, Joshua M. Pearce Mar 2018

Open Source Multi-Head 3d Printer For Polymer-Metal Composite Component Manufacturing, J. Laureto, Joshua M. Pearce

Joshua M. Pearce

As low-cost desktop 3D printing is now dominated by free and open source self-replicating rapid prototype (RepRap) derivatives, there is an intense interest in extending the scope of potential applications to manufacturing. This study describes a manufacturing technology that enables a constrained set of polymer-metal composite components. This paper provides (1) free and open source hardware and (2) software for printing systems that achieves metal wire embedment into a polymer matrix 3D-printed part via a novel weaving and wrapping method using (3) OpenSCAD and parametric coding for customized g-code commands. Composite parts are evaluated from the technical viability of manufacturing …


Impact Of Diy Home Manufacturing With 3d Printing On The Toy And Game Market, Emily Peterson, Joshua M. Pearce Mar 2018

Impact Of Diy Home Manufacturing With 3d Printing On The Toy And Game Market, Emily Peterson, Joshua M. Pearce

Joshua M. Pearce

The 2020 toy and game market is projected to be US$135 billion. To determine if 3D printing could affect these markets if consumers offset purchases by 3D printing free designs, this study investigates the 100 most popular downloaded designs at MyMiniFactory in a month. Savings are quantified for using a Lulzbot Mini 3D printer and three filament types: commercial filament, pellet-extruded filament, and post-consumer waste converted to filament with a recyclebot. Case studies probed the quality of: (1) six common complex toys; (2) Lego blocks; and (3) the customizability of open source board games. All filaments analyzed saved the user …


Open Source 3-D Printed Nutating Mixer, Dhwani K. Trivedi, Joshua M. Pearce Mar 2018

Open Source 3-D Printed Nutating Mixer, Dhwani K. Trivedi, Joshua M. Pearce

Joshua M. Pearce

As the open source development of additive manufacturing has led to low-cost desktop three-dimensional (3-D) printing, a number of scientists throughout the world have begun to share digital designs of free and open source scientific hardware. Open source scientific hardware enables custom experimentation, laboratory control, rapid upgrading, transparent maintenance, and lower costs in general. To aid in this trend, this study describes the development, design, assembly, and operation of a 3-D printable open source desktop nutating mixer, which provides a fixed 20° platform tilt angle for a gentle three-dimensional (gyrating) agitation of chemical or biological samples (e.g., DNA or blood …


Evaluation And Enhancement Of Solar Chimney Power Plant, Nima Fathi Mar 2018

Evaluation And Enhancement Of Solar Chimney Power Plant, Nima Fathi

Nima Fathi

Clean (and specifically renewable) energy is steadily improving its global share. However, finite availability of fossil fuels and the growing effects of climate change make it an urgent priority to convince the industry and governments to incentivize investment in the renewable energy field and to make it more attractive by decreasing the capital cost. Until recently, uncertainties in funding limited renewable energy development, especially in the US. That limitation has been one of the barriers to progress. Another limitation of many renewable energy systems is the variability in their output, which makes them unsuitable for baseline power production. Therefore, fossil …


Crack Growth Induced By Sonic Ir Inspection, John C. Chen, Jacob Kephart, Kyle Lick, William T. Riddell Feb 2018

Crack Growth Induced By Sonic Ir Inspection, John C. Chen, Jacob Kephart, Kyle Lick, William T. Riddell

William Riddell

We have developed an experiment to study the propagation of laboratory-synthesized fatigue cracks under various controlled conditions during Sonic IR inspection. The experiment provides for good repeatability in testing. The parameters of interest include the initial crack length, load history (stress intensity and load ratio) during crack generation, geometry of the crack, material and also the various conditions involving the ultrasonic excitation source. In general, we find that under typical sonic IR inspection conditions, the initial crack will propagate under sonic IR testing. The crack growth after each inspection event varies and exhibits a distribution in length of propagation. The …


Sure Abstract - Spring 2018: Analysis And Application Of Biomimetic Metamaterial Scales, Ryan Horton Feb 2018

Sure Abstract - Spring 2018: Analysis And Application Of Biomimetic Metamaterial Scales, Ryan Horton

Ryan Horton

No abstract provided.


Prediction Of Solid Oxide Fuel Cell Performance Using Artificial Neural Network, M. A. Rafe Biswas, Kamwana N. Mwara Oct 2017

Prediction Of Solid Oxide Fuel Cell Performance Using Artificial Neural Network, M. A. Rafe Biswas, Kamwana N. Mwara

M. A. Rafe Biswas

NASA’s Johnson Space Center has recently begun efforts to eventually integrate air-independent Solid Oxide Fuel Cell (SOFC) systems, with landers that can be propelled by LOX-CH4, for long duration missions. Using landers that utilize such propellants, provides the opportunity to use SOFCs as a power option, especially since they are able to process methane into a reactant through fuel reformation. Various lead-up activities, such as hardware testing and computational modelling, have been initiated to assist with this developmental effort.
One modeling approach, currently being explored to predict SOFC behavior, involves the usage of artificial neural networks (ANN). Since SOFC performance …


The Girl Scout Climbing Wall Multidisciplinary Service-Learning Project, Margaret Pinnell, Corinne M. Daprano, Gabrielle Williamson Oct 2017

The Girl Scout Climbing Wall Multidisciplinary Service-Learning Project, Margaret Pinnell, Corinne M. Daprano, Gabrielle Williamson

Corinne M. Daprano

The Girl Scout Wall (GS Wall) project was implemented in two classes at the University of Dayton (UD): a Mechanical and Aerospace Engineering (MAE) course, and a Health and Sports Science (HSS) course, and Sport Facility Management. The MAE course, Introduction to Materials, is a three-credit, third-year required course where students learn about the basic structure and properties of materials as well as the principles of material selection. The Sport Facility Management course is a three-semester hour, required HSS course where students are introduced to the processes of planning, constructing, equipping, maintaining, and managing sport facilities.


Cfd Simulation Of Passenger Hazard Risk At Railway Station Platforms Due To Explosive Air Blasts, Vivian Lawrence, Sakdirat Kaewunruen, Gianni Bartoli, Charalampos Baniotopoulos Aug 2017

Cfd Simulation Of Passenger Hazard Risk At Railway Station Platforms Due To Explosive Air Blasts, Vivian Lawrence, Sakdirat Kaewunruen, Gianni Bartoli, Charalampos Baniotopoulos

Sakdirat Kaewunruen

Safety is the first priority in operating transportation and transit systems. The public and customers rely on operators to assure them the reliable and safe day-to-day uses of public transports. However, based on recent factual evidences, extreme physical and cyber threats are no longer uncommon and these unpreventable measures are even more dangerous to the public’s daily lives. Such clear examples are the terrorist attacks in Saint Petersburg in 2017, in London in 2017, in Stockholm in 2017, in Brussels in 2016, in Nice in 2016, and so many more. These examples have one thing in common. The transportation and …


Application Of Pca To Cardiac Optical Mapping, Louis Woodhams Aug 2017

Application Of Pca To Cardiac Optical Mapping, Louis Woodhams

Louis Woodhams

Structural remodeling of the heart due to pathologies such as hypertension and myocardial infarction leads to the appearance of myofibroblasts, a phenotype largely absent in physiologic myocardium. While myofibroblasts are responsible for wound healing and structural repair of damaged myocardium, they are thought to have deleterious effects on electrical and mechanical properties of the heart. Understanding these effects is critical to developing effective treatments, and has motivated the development of a series of in vitro engineered heart tissues and cardiomyocyte-myofibroblast co-cultures whose mechanical and electrophysiological function can be deduced from video analysis. Electrophysiological properties are evident from changes in intensity …


Induction Heating Of Thin Films, Paul L. Bergstrom, Melissa L. Trombley Aug 2017

Induction Heating Of Thin Films, Paul L. Bergstrom, Melissa L. Trombley

Paul Bergstrom

A method of performing regional heating of a system having a substrate. The method may include applying a thin film to the system, and controllably energizing a coil positioned near the thin film. The energized coils thereby generate a magnetic flux. The method further includes inducing a current in the thin film with the magnetic flux thereby heating the system.


Presentation Of Double Inlet Scpp, Nima Fathi, Seyed Sobhan Aleyasin, Patrick Wayne, Peter Vorobieff Jul 2017

Presentation Of Double Inlet Scpp, Nima Fathi, Seyed Sobhan Aleyasin, Patrick Wayne, Peter Vorobieff

Nima Fathi

No abstract provided.


Evaluation And Enhancement Of Clean Energy Systems: Analytical, Computational And Experimental Study Of Solar And Nuclear Cycles, Nima Fathi Jul 2017

Evaluation And Enhancement Of Clean Energy Systems: Analytical, Computational And Experimental Study Of Solar And Nuclear Cycles, Nima Fathi

Nima Fathi

Clean (and specifically renewable) energy is steadily improving its global share. However, finite availability of fossil fuels and the growing effects of climate change make it an urgent priority to convince the industry and governments to incentivize investment in the renewable energy field and to make it more attractive by decreasing the capital cost. Until recently, uncertainties in funding limited renewable energy development, especially in the US. That limitation has been one of the barriers to progress. Another limitation of many renewable energy systems is the variability in their output, which makes them unsuitable for baseline power production. Therefore, fossil …


Us Patent 9,702,573: Nested Heat Transfer System, Sanza Kazadi Jul 2017

Us Patent 9,702,573: Nested Heat Transfer System, Sanza Kazadi

Sanza Kazadi

A novel nested heat transfer system comprises a plurality of chained enhanced entrochemical cells with nested structures. Each enhanced entrochemical cell includes a first chamber containing desiccant, or a higher concentration solution, and a second chamber containing refrigerant,   or   a   lower   concentration   solution.   Preferably,   the   first   chamber   and   the   second   chamber   are   connected   by   a   conduit.  Furthermore,   a   smaller   chamber   in   an   enhanced   entrochemical   cell   is   encapsulated   by   a   larger   chamber   in   an   adjacent   enhanced entrochemical cell, thus forming a nested structure between the two enhanced entrochemical cells. A chain of enhanced entrochemical cells with a plurality of such nested …


Us Patent 9,702,633: Entrochemical Energy Transfer System And A Process For Obtaining Work From Environmental Thermal Energy, Sanza Kazadi Jul 2017

Us Patent 9,702,633: Entrochemical Energy Transfer System And A Process For Obtaining Work From Environmental Thermal Energy, Sanza Kazadi

Sanza Kazadi

An entrochemical energy transfer system and a related process for obtaining work from environmental thermal energy are disclosed. In one   example,   a   plurality   of   linked   entrochemical   cells   with   nested   chambers   provides   an   aggregate   thermal   gradient   of   each entrochemical   cell   by   transferring   environmental   thermal   energy   in   and/or   out   of   the   plurality   of   linked   entrochemical   cells.   The aggregate thermal gradient generated from the plurality of linked entrochemical cells can be utilized as an environmentally­ friendly energy source for human needs. The entrochemical energy transfer system and the related process for obtaining work from environmental thermal energy utilize a set of entropy transfers …


Direct Numerical Simulation Of Turbulent Katabatic Slope Flows With An Immersed-Boundary Method, Clancy Umphrey, Ray Deleon, Inanc Senocak Jun 2017

Direct Numerical Simulation Of Turbulent Katabatic Slope Flows With An Immersed-Boundary Method, Clancy Umphrey, Ray Deleon, Inanc Senocak

Inanc Senocak

We investigate a Cartesian-mesh immersed-boundary formulation within an incompressible flow solver to simulate laminar and turbulent katabatic slope flows. As a proof-of-concept study, we consider four different immersed-boundary reconstruction schemes for imposing a Neumann-type boundary condition on the buoyancy field. Prandtl’s laminar solution is used to demonstrate the second-order accuracy of the numerical solutions globally. Direct numerical simulation of a turbulent katabatic flow is then performed to investigate the applicability of the proposed schemes in the turbulent regime by analyzing both first- and second-order statistics of turbulence. First-order statistics show that turbulent katabatic flow simulations are noticeably sensitive to the …


Dynamic Rating Of Overhead Transmission Lines Over Complex Terrain Using A Large-Eddy Simulation Paradigm, Tyler Phillips, Ray Deleon, Inanc Senocak Jun 2017

Dynamic Rating Of Overhead Transmission Lines Over Complex Terrain Using A Large-Eddy Simulation Paradigm, Tyler Phillips, Ray Deleon, Inanc Senocak

Inanc Senocak

Dynamic Line Rating (DLR) enables rating of power line conductors using real-time weather conditions. Conductors are typically operated based on a conservative static rating that assumes worst case weather conditions to avoid line sagging to unsafe levels. Static ratings can cause unnecessary congestion on transmission lines. To address this potential issue, a simulation-based dynamic line rating approach is applied to an area with moderately complex terrain. A micro-scale wind solver — accelerated on multiple graphics processing units (GPUs) — is deployed to compute wind speed and direction in the vicinity of powerlines. The wind solver adopts the large-eddy simulation technique …


Vector Acoustic Intensity Around A Tuning Fork, Daniel A. Russell, Justin Junell, Daniel O. Ludwigsen May 2017

Vector Acoustic Intensity Around A Tuning Fork, Daniel A. Russell, Justin Junell, Daniel O. Ludwigsen

Daniel Ludwigsen

The acoustic intensity vector field around a tuning fork is investigated. Theory for a longitudinal quadrupole source predicts a well-defined transition between near-field and far-field, with significant circulation of sound energy in the near-field. Vector components of the time-averaged intensity were measured using a two-microphone intensity probe and found to agree well with predictions from theory. The vector intensity map is interpreted, and shown to provide useful information about the near-field of an acoustic source.


Better Understanding Of Resonance Through Modeling And Visualization, Daniel O. Ludwigsen, Cayla Jewett, Matthew Jusczcyk May 2017

Better Understanding Of Resonance Through Modeling And Visualization, Daniel O. Ludwigsen, Cayla Jewett, Matthew Jusczcyk

Daniel Ludwigsen

Students encounter cavity resonance and waveguide phenomena in acoustics courses and texts, where the study is usually limited to cases with simple geometries: parallelepipeds, cylinders, and spheres. Long-wavelength approximations help with situations of more complexity, as in the classic Helmholtz resonator. At Kettering University, we are beginning to employ finite element modeling in our acoustics classes to help undergraduates better understand the acoustic modes of actual structures. This approach to the time-independent wave equation (the Helmholtz equation) was first used in a research and measurements class to investigate two classic resonance problems. The first problem was a study of resonance …


Acoustic Testing And Modeling: An Advanced Undergraduate Laboratory, Daniel A. Russell, Daniel O. Ludwigsen May 2017

Acoustic Testing And Modeling: An Advanced Undergraduate Laboratory, Daniel A. Russell, Daniel O. Ludwigsen

Daniel Ludwigsen

This paper describes an advanced laboratory course in acoustics, specifically targeted for students with an interest in engineering applications at a school with a strongly integrated industrial co-op program. The laboratory course is developed around a three-pronged approach to problem solving that combines and integrates theoretical models, computational models, and experimental data. The course is structured around modules that begin with fundamental concepts and build laboratory skills and expand the knowledge base toward a final project. Students keep a detailed laboratory notebook, write research papers in teams, and must pass laboratory certification exams. This paper describes the course layout and …


Lube Oil Chemistry Influences On Autoignition As Measured In An Ignition Quality Tester, Francis M. Haas, Sang Hee Won, Frederick L. Dryer, Cécile Pera Mar 2017

Lube Oil Chemistry Influences On Autoignition As Measured In An Ignition Quality Tester, Francis M. Haas, Sang Hee Won, Frederick L. Dryer, Cécile Pera

Francis (Mac) Haas

Derived Cetane Numbers (DCNs) of engine lubricating oil/ 95 Research Octane Number gasoline surrogate mixtures are measured in an Ignition Quality Tester. These measurements separately screen for effects of (1) calcium- and magnesium-based detergent additive, (2) oil degradation, and (3) base oil on mixture ignition propensity at conditions relevant to low speed pre-ignition (LSPI) in gasoline engines. Initial testing of ≤ 25% mass oil in the gasoline surrogate indicates a positive linear relationship between DCN and blend fraction, and also demonstrates the sensitivity of the measurement technique to mixture composition. Despite variation in Ca and Mg concentrations, DCN responses for …


Chemical Functional Group Descriptor For Jet Fuel Surrogate, Sang Hee Won, Francis M. Haas, Stephen Dooley, Frederick L. Dryer Mar 2017

Chemical Functional Group Descriptor For Jet Fuel Surrogate, Sang Hee Won, Francis M. Haas, Stephen Dooley, Frederick L. Dryer

Francis (Mac) Haas

The global chemical characters of complex chemical fuel mixtures are explicitly determined by evaluating the abundances of chemical functional groups present within it rather by applying molecular species composition. Statistical analyses on the relationships of each chemical functional group and the chemical property targets of the fuel are rigorously developed. The results demonstrate that the four CPTs currently used in surrogate formulation - H/C molar ratio, derived cetane number (DCN), average molecular weight (MW), and smoke point (SP) - effectively constrain the chemical function group distribution of the fuel, hence, the global combustion behaviors of pre-vaporized fuel/air mixtures. Emulating the …


Optimizing Compressed Air Storage For Energy Efficiency, Brian Abels, J. Kelly Kissock Mar 2017

Optimizing Compressed Air Storage For Energy Efficiency, Brian Abels, J. Kelly Kissock

J. Kelly Kissock

Compressed air storage is an important, but often misunderstood, component of compressed air systems. This paper discusses methods to properly size compressed air storage in load-unload systems to avoid short cycling and reduce system energy use. First, key equations relating storage, pressure, and compressed air flow are derived using fundamental thermodynamic relations. Next, these relations are used to calculate the relation between volume of storage and cycle time in load-unload compressors. It is shown that cycle time is minimized when compressed air demand is 50% of compressor capacity. The effect of pressure drop between compressor system and storage on cycle …


Lean Energy Analysis: Identifying, Discovering And Tracking Energy Savings Potential, J. Kelly Kissock, John Seryak Mar 2017

Lean Energy Analysis: Identifying, Discovering And Tracking Energy Savings Potential, J. Kelly Kissock, John Seryak

J. Kelly Kissock

Energy in manufacturing facilities is used for direct production of goods, space conditioning, and general facility support such as lighting. This paper presents a methodology, called lean energy analysis, LEA, for graphically and statistically analyzing plant energy use in terms of these major end uses.

The LEA methodology uses as few as 60 easily obtainable data points. Multivariable change-point models of electricity and natural gas use as functions of outdoor air temperature and production data are developed. The statistical models are used to subdivide plant energy use into facility, space-conditioning and production-related components.

These breakdowns suggest the savings potential from …


Energy Efficient Process Heating: Insulation And Thermal Mass, Kevin Carpenter, J. Kelly Kissock Mar 2017

Energy Efficient Process Heating: Insulation And Thermal Mass, Kevin Carpenter, J. Kelly Kissock

J. Kelly Kissock

Open tanks and exterior surfaces of process heating equipment lose heat to the surroundings via convection, radiation, and/or evaporation. A practical way of reducing heat loss is by insulating or covering the surfaces. This paper presents methods to quantify heat loss and energy savings from insulating hot surfaces and open tanks. The methods include radiation and evaporation losses, which are ignored by simplified methods. In addition, thermal mass, such as refractory, conveyor and racking equipment, acts as a heat sink and increases heating energy use in process heating applications. This paper presents lumped capacitance and finite-difference methods for estimating heat …


Improving Compressed Air Energy Efficiency In Automotive Plants: Practical Examples And Implementation, Nasr Alkadi, J. Kelly Kissock Mar 2017

Improving Compressed Air Energy Efficiency In Automotive Plants: Practical Examples And Implementation, Nasr Alkadi, J. Kelly Kissock

J. Kelly Kissock

The automotive industry is the largest industry in the United States in terms of the dollar value of production [1]. U.S. automakers face tremendous pressure from foreign competitors, which have an increasing manufacturing presence in this country. The Big Three North American Original Equipment Manufacturers (OEMs)-General Motors, Ford, and Chrysler-are reacting to declining sales figures and economic strain by working more efficiently and seeking out opportunities to reduce production costs without negatively affecting the production volume or the quality of the product. Successful, cost-effective investment and implementation of the energy efficiency technologies and practices meet the challenge of maintaining the …


Energy Efficient Process Heating: Managing Air Flow, Kevin Carpenter, J. Kelly Kissock Mar 2017

Energy Efficient Process Heating: Managing Air Flow, Kevin Carpenter, J. Kelly Kissock

J. Kelly Kissock

Much energy is lost through excess air flow in and out of process heating equipment. Energy saving opportunities from managing air flow include minimizing combustion air, preheating combustion air, minimizing ventilation air, and reconfiguring openings to reduce leakage.

This paper identifies these opportunities and presents methods to quantify potential energy savings from implementing these energy-savings measures. Case study examples are used to demonstrate the methods and the potential energy savings.The method for calculating savings from minimizing combustion air accounts for improvement in efficiency from increased combustion temperature and decreased combustion gas mass flow rate.

The method for calculating savings from …


Measuring Plant-Wide Energy Savings, J. Kelly Kissock, Carl Eger Mar 2017

Measuring Plant-Wide Energy Savings, J. Kelly Kissock, Carl Eger

J. Kelly Kissock

This paper presents a general method for measuring plant-wide industrial energy savings and demonstrates the method using a case study from an actual industrial energy assessment. The method uses regression models to characterize baseline energy use. It takes into account changes in weather and production, and can use sub-metered data or whole plant utility billing data. In addition to calculating overall savings, the method is also able to disaggregate savings into components, which provides additional insight into the effectiveness of the individual savings measures. Although the method incorporates search techniques and multi-variable least-squares regression, it is easily implemented using data …