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Articles 1141 - 1170 of 4850

Full-Text Articles in Engineering

Developable Mechanisms On Developable Surfaces, Todd G. Nelson, Trent K. Zimmerman, Robert J. Lang, Spencer P. Magleby, Larry L. Howell Feb 2019

Developable Mechanisms On Developable Surfaces, Todd G. Nelson, Trent K. Zimmerman, Robert J. Lang, Spencer P. Magleby, Larry L. Howell

Faculty Publications

The trend toward smaller mechanism footprints and volumes, while maintaining the ability to perform complex tasks, presents the opportunity for exploration of hypercompact mechanical systems integrated with curved surfaces. Developable surfaces are shapes that a flat sheet can take without tearing or stretching, and they represent a wide range of manufactured surfaces. This work introduces “developable mechanisms” as devices that emerge from or conform to developable surfaces. They are made possible by aligning hinge axes with developable surface ruling lines to enable mobility. Because rigid-link motion depends on the relative orientation of hinge axes and not link geometry, links can …

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Model Predictive Automatic Control Of Sucker Rod Pump System With Simulation Case Study, Brigham Hansen, Brandon Tolbert, Cory Vernon, John Hedengren Feb 2019

Model Predictive Automatic Control Of Sucker Rod Pump System With Simulation Case Study, Brigham Hansen, Brandon Tolbert, Cory Vernon, John Hedengren

Faculty Publications

This work enables accelerated fluid recovery in oil and gas reservoirs by automatically controlling fluid height and bottomhole pressure in wells. Several literature studies show significant increase in recovered oil by determining a target bottomhole pressure but rarely consider how to control to that value. This work enables those benefits by maintaining bottomhole pressure or fluid height. Moving Horizon Estimation (MHE) determines uncertain well parameters using only common surface measurements. A Model Predictive Controller (MPC) adjusts the stroking speed of a sucker rod pump to maintain fluid height. Pump boundary conditions are simulated with Mathematical Programs with Complementarity Constraints (MPCCs) …

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Influence Of Micro-Structured Superhydrophobic Surfaces On Nucleation And Natural Convection In A Heated Pool, Adam Cowley, Daniel Maynes, Julie Crockett, Brian D. Iverson Feb 2019

Influence Of Micro-Structured Superhydrophobic Surfaces On Nucleation And Natural Convection In A Heated Pool, Adam Cowley, Daniel Maynes, Julie Crockett, Brian D. Iverson

Faculty Publications

This word experimentally explores sub-boiling pool nucleation on micro-structured superhydrophobic surfaces. All surfaces tested were submerged in a 20 mm deep pool of water and heated from below to maintain a constant surface temperature, while the side walls of the pool were insulated, and the top was covered. Three thermocouples positioned in the pool obtain the average pool temperature. A heat flux sensor is placed directly beneath the surface to measure the heat flux supplied to the pool. Free convection heat transfer coefficients are obtained for the sub-boiling temperature range of 40 – 90 ºC. Six surface types are studied: …

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The Sap Link: A Controller Architecture For Secure Industrial Control Systems, Matthew Cody Wyman Feb 2019

The Sap Link: A Controller Architecture For Secure Industrial Control Systems, Matthew Cody Wyman

Theses and Dissertations

Industrial Control Systems are essential to modern life. They are utilized in hundreds of processes including power distribution, water treatment, manufacturing, traffic management, and amusement park ride control. These systems are an essential part of modern life and if compromised, could result in significant economic loss, safety impacts, damage to the environment, and even loss of life. Unfortunately, many of these systems are not properly secured from a cyber attack. It is likely that a well-funded and motivated attack from a nation-state will successfully compromise an industrial control system's network. As cyber war becomes more prevalent, it is becoming more …

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Beating Clusters Created With Cardiac Extracellular Matrix From Decellularized Pig Hearts And Repopulated With Human Induced Pluripotent Stem Cell-Derived Cardiomyocytes, Isaac Myres, Bryce Allen, Silvia Moncada, Sebastian Valencia, Beverly L. Roeder, Alonzo D. Cook Jan 2019

Beating Clusters Created With Cardiac Extracellular Matrix From Decellularized Pig Hearts And Repopulated With Human Induced Pluripotent Stem Cell-Derived Cardiomyocytes, Isaac Myres, Bryce Allen, Silvia Moncada, Sebastian Valencia, Beverly L. Roeder, Alonzo D. Cook

Library/Life Sciences Undergraduate Poster Competition 2019

Due to the high prevalence of heart disease, scarcity of donors, and high risk of transplant rejection, we aim to engineer patient specific beating cardiac patches and whole hearts for transplant.

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The Effect Of Communication And Vehicle Properties On The Search Performance Of A Swarm Of Unmanned Aerial Vehicles, Jenna E. Newcomb, Andrew Ning Jan 2019

The Effect Of Communication And Vehicle Properties On The Search Performance Of A Swarm Of Unmanned Aerial Vehicles, Jenna E. Newcomb, Andrew Ning

Faculty Publications

An unmanned aerial vehicle (UAV) swarm allows for a more time-efficient method of searching a specified area than a single UAV or piloted plane. There are a variety of factors that affect how well an area is surveyed. We specifically analyzed the effect both vehicle properties and communication had on the swarm search performance. We used non-dimensionalization to examine the effect vehicle properties had on search performance so the results can be applied to any domain size with any number and type of vehicle. We found that even if vehicles could only sense 10% of the grid area at any …

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Modified Cpd Model For Coal Devolatilization At Underground Coal Thermal Treatment Conditions, Ding Wang, Thomas H. Fletcher, Swomitra Mohanty, Hoaquan Hu, Eric G. Eddings Jan 2019

Modified Cpd Model For Coal Devolatilization At Underground Coal Thermal Treatment Conditions, Ding Wang, Thomas H. Fletcher, Swomitra Mohanty, Hoaquan Hu, Eric G. Eddings

Faculty Publications

To study coal pyrolysis behavior at underground coal thermal treatment (UCTT) conditions, a modified CPD (M-CPD) model was developed and evaluated using two scales of experiments as well as two different coals, Utah Sufco and Illinois #6. Compared with the original CPD model, three major aspects were changed, including (1) rewriting the algorithm using MATLAB built-in functions; (2) developing a correlation method between coal elemental composition and the initial functional group population to calculate the effect of cross-linking on the lattice structure; and (3) using a two-activation energy approach for gas generation kinetics modeling. Results predicted by the M-CPD model …

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Pyrolysis Kinetics Of Live And Dead Wildland Vegetation From The Southern United States, Elham Amini, Mohammad-Saeed Safdari, David R. Weise, Thomas H. Fletcher Jan 2019

Pyrolysis Kinetics Of Live And Dead Wildland Vegetation From The Southern United States, Elham Amini, Mohammad-Saeed Safdari, David R. Weise, Thomas H. Fletcher

Faculty Publications

The fundamental combustion behavior of live wildland vegetation is not fully understood. Since the combustion process during wildland fire starts with pyrolysis, there is a need for better understanding of pyrolysis to develop improved wildland fire models. The kinetics of pyrolysis of live and dead wildland vegetation has not been explored in detail. In this study, the pyrolysis kinetics were determined for 14 different plant species (live and dead) which are all native to the forests in the southern United States. Pyrolysis experiments were carried out in a Thermogravimetric analyzer (TGA) under inert conditions at 5 different heating rates ranged …

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Characterization Of Pyrolysis Products From Slow Pyrolysis Of Live And Dead Vegetation Native To The Southern United States, Elham Amini, Mohammad-Saeed Safdari, Jonathan Deyoung, David R. Weise, Thomas H. Fletcher Jan 2019

Characterization Of Pyrolysis Products From Slow Pyrolysis Of Live And Dead Vegetation Native To The Southern United States, Elham Amini, Mohammad-Saeed Safdari, Jonathan Deyoung, David R. Weise, Thomas H. Fletcher

Faculty Publications

Prescribed (i.e., controlled) burning is a common practice used in many vegetation types in the world to accomplish a wide range of land management objectives including wildfire risk reduction, wildlife habitat improvement, forest regeneration, and land clearing. To properly apply controlled fire and reduce unwanted fire behavior, an improved understanding of fundamental processes related to combustion of live and dead vegetation is needed. Since the combustion process starts with pyrolysis, there is a need for more data and better models of pyrolysis of live and dead fuels. In this study, slow pyrolysis experiments were carried out in a pyrolyzer apparatus …

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Optimization Of Turbine Design In Wind Farms With Multiple Hub Heights, Using Exact Analytic Gradients And Structural Constraints, Andrew P.J. Stanley, Andrew Ning, Katherine Dykes Jan 2019

Optimization Of Turbine Design In Wind Farms With Multiple Hub Heights, Using Exact Analytic Gradients And Structural Constraints, Andrew P.J. Stanley, Andrew Ning, Katherine Dykes

Faculty Publications

Wind farms are generally designed with turbines of all the same hub height. If wind farms were designed with turbines of different hub heights, wake interference between turbines could be reduced, lowering the cost of energy (COE). This paper demonstrates a method to optimize onshore wind farms with two different hub heights using exact, analytic gradients. Gradient-based optimization with exact gradients scales well with large problems and is preferable in this application over gradient-free methods. Our model consisted of the following: a version of the FLOw Redirection and Induction in Steady-State wake model that accommodated three- dimensional wakes and calculated …

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Combined Trajectory, Propulsion, And Battery Mass Optimization For Solar-Regenerative High-Altitude Long Endurance Unmanned Aircraft, Nathaniel S. Gates, Kevin R. Moore, Andrew Ning, John D. Hedengren Jan 2019

Combined Trajectory, Propulsion, And Battery Mass Optimization For Solar-Regenerative High-Altitude Long Endurance Unmanned Aircraft, Nathaniel S. Gates, Kevin R. Moore, Andrew Ning, John D. Hedengren

Faculty Publications

Combined optimization of propulsion system design, flight trajectory planning and battery mass optimization for solar-regenerative high-altitude long endurance (SRHALE) aircraft through a sequential iterative approach yields an increase of 20.2% in the end-of-day energy available on the winter solstice at 35 deg N latitude, resulting in an increase in flight time of 2.36 hours. The optimized flight path is obtained by using nonlinear model predictive control to solve flight and energy system dynamics over a 24 hour period with a 15 second time resolution. The optimization objective is to maximize the total energy in the system while flying a station-keeping …

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Heating Rate And Temperature Effects On Pyrolysis Products From Live Wildland Fuels, Mohammad-Saeed Safdari, Elham Amini, David R. Weise, Thomas H. Fletcher Jan 2019

Heating Rate And Temperature Effects On Pyrolysis Products From Live Wildland Fuels, Mohammad-Saeed Safdari, Elham Amini, David R. Weise, Thomas H. Fletcher

Faculty Publications

Wildland fire, which includes both planned (prescribed fire) and unplanned (wildfire) fires, is an important component of many ecosystems. During wildland fires, low heating rate pyrolysis (slow pyrolysis) occurs during preheating and/or smoldering of plant material. High heating rate pyrolysis (fast pyrolysis) exists in the flame region. Pyrolysis temperature and heating rate play important roles on the yields and the compositions of pyrolysis products. In this work, the effects of pyrolysis temperature and heating rate on the yields and the compositions of pyrolysis products from 14 plant species native to the forests of the southern United States are shown. The …

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Review Of Carbonaceous Annealing Effects On O2 And Co2 Coal Reactivity, Troy Michael Holland, Thomas H. Fletcher, Osvalda Senneca Jan 2019

Review Of Carbonaceous Annealing Effects On O2 And Co2 Coal Reactivity, Troy Michael Holland, Thomas H. Fletcher, Osvalda Senneca

Faculty Publications

Coal is, and will remain for the foreseeable future, a critical energy production resource. Advanced models of coal conversion behavior in air and oxy-coal environments enhance the boiler operational efficiency and design optimization. Although coal conversion models have continuously improved over decades of research, not all aspects of coal particle heating and conversion have received equal treatment. Coal particle annealing is one aspect of the coal conversion process that is simultaneously highly sensitive to the conversion environment, exceptionally impactful on coal chemistry, and frequently neglected in coal models. However, the current body of literature has explored numerous aspects of coal …

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Correlations Of The Elemental Compositions Of Primary Coal Tar And Char, Andrew P. Richards, Colson Johnson, Thomas H. Fletcher Jan 2019

Correlations Of The Elemental Compositions Of Primary Coal Tar And Char, Andrew P. Richards, Colson Johnson, Thomas H. Fletcher

Faculty Publications

Simulations of large-scale coal combustors rely on accurate submodels to describe the chemical and physical changes in coal during reaction. Typically, simplified empirical submodels are tuned to experimental data to reduce the computational complexity. When data are not readily available, simplifying assumptions are used, which can create inaccuracies and biases in a large simulation. One such simplifying assumption in coal research is how to describe the elemental composition of primary pyrolysis products. This paper explores several different empirical model forms to predict the dry, ash-free fractions of C, H, O, N, and S in both the char and tar, using …

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Integrating Global And Local Forecasting Resources And Methods For Flood Warning Systems In Central America And Caribbean Region, José Fidel Pérez Dec 2018

Integrating Global And Local Forecasting Resources And Methods For Flood Warning Systems In Central America And Caribbean Region, José Fidel Pérez

Theses and Dissertations

Hurricanes and tropical storms occur very frequently in the Central American and Caribbean Region (CA&CR). These extreme weather events produce a lot of rain and consequently a lot of flooding. Damages and loses have been estimated to amount to 13.4 billion dollars in the last ten years. Flood Warning Systems (FEWS) are a key preventive strategy to reduce risk. Technological progress is improving the resources made available for FEWS to be more viable. In spite of the international support for FEWS and the fast development of ICT, there are very few countries in the CA&CR that have succeeded in developing …

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Wall Shear Stress In Simplified And Scanned Avian Respiratory Airways, Michael Sterling Farnsworth Dec 2018

Wall Shear Stress In Simplified And Scanned Avian Respiratory Airways, Michael Sterling Farnsworth

Theses and Dissertations

Birds uniquely produce sound through a vocal organ known as a syrinx. The presence of wall shear stress acting on the airway cells of any organism will affect how airway cells develop and multiply. Unique features of avian airway geometry and breathing pattern might have contributed to the development of the syrinx. This thesis examines wall shear stress in the trachea and first bronchi of avian geometries using computational fluid dynamics. The computational fluid dynamic simulations underwent grid- and time-independence studies and were validated using particle image velocimetry. Parameters such as bird size, bronchial branching angle, and breathing waveform were …

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An Analytical Model Of Material Deformation In Rotary Friction Welding Of Thin-Walled Tubes, Caleb James Brown Dec 2018

An Analytical Model Of Material Deformation In Rotary Friction Welding Of Thin-Walled Tubes, Caleb James Brown

Theses and Dissertations

A new model of the material flow in rotary friction welding of tubes is proposed. The material flow proposed is based on 3D scans of welds performed with tungsten tracers. The tracers indicate a bifurcation of flow into two deformation paths. A different analysis is performed on each path.The material in Path 1 interacts with the weld interface and exhibits large amounts of azimuthal flow. Previous analytical investigations that have analytically modelled the weld interface as a non-Newtonian fluid are used to calculate the strain rate in this zone.The material in Path 2 transitions from axial to primarily radial flow. …

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Engineering Cell-Free Biosystems For On-Site Production And Rapid Design Of Next-Generation Therapeutics, Kristen Michelle Wilding Dec 2018

Engineering Cell-Free Biosystems For On-Site Production And Rapid Design Of Next-Generation Therapeutics, Kristen Michelle Wilding

Theses and Dissertations

While protein therapeutics are indispensable in the treatment of a variety of diseases, including cancer, rheumatoid arthritis, and diabetes, key limitations including short half-lives, high immunogenicity, protein instability, and centralized production complicate long-term use and on-demand production. Site-specific polymer conjugation provides a method for mitigating these challenges while minimizing negative impacts on protein activity. However, the location-dependent effects of polymer conjugation are not well understood. Cell-free protein synthesis provides direct access to the synthesis environment and rapid synthesis times, enabling rapid evaluation of multiple conjugation sites on a target protein. Here, work is presented towards developing cell-free protein synthesis as …

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Conceptual Design Of A Pilot-Scale Pressurized Coal-Feed System, Taylor L. Schroedter Dec 2018

Conceptual Design Of A Pilot-Scale Pressurized Coal-Feed System, Taylor L. Schroedter

Theses and Dissertations

This thesis discusses the results and insights gained from developing a CFD model of a pilot-scale pressurized dry coal-feed system using the Barracuda CFD software and modeling various design concepts and operating conditions. The feed system was required to transport approximately 0.00378 kg/s (30 lb/hr) of pulverized coal from a vertical hopper to a 2.07 MPa (20.4 atm or 300 psi) reactor with a CO2-to-coal mass flow ratio of 1-2. Two feed system concepts were developed and tested for coal mass flow, CO2-to-coal mass ratio, steadiness, and uniformity. Piping system components also were evaluated for pressure drop and coal roping.With …

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Large-Scale Testing Of Low-Strength Cellular Concrete For Skewed Bridge Abutments, Rebecca Eileen Black Dec 2018

Large-Scale Testing Of Low-Strength Cellular Concrete For Skewed Bridge Abutments, Rebecca Eileen Black

Theses and Dissertations

Low-strength cellular concrete is a type of controlled low-strength material (CLSM) which is increasingly being used for various modern construction applications. Benefits of the material include its ease of placement due to the ability of cellular concrete to self-level and self-compact. It is also extremely lightweight compared to traditional concrete, enabling the concrete to be used in fill applications as a compacted soil would customarily be used. Testing of this material is not extensive, especially in the form of large-scale tests. Additionally, effects of skew on passive force resistance help to understand performance of a material when it is used …

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Repopulation And Stimulation Of Porcine Cardiac Extracellular Matrix To Create Engineered Heart Patches, Silvia Juliana Moncada Diaz Dec 2018

Repopulation And Stimulation Of Porcine Cardiac Extracellular Matrix To Create Engineered Heart Patches, Silvia Juliana Moncada Diaz

Theses and Dissertations

Heart failure is the main cause of death for both men and women in the United States. The only proven treatment for patients with heart failure is heart transplantation. The goal of this research is to create patches of tissue that could mimic the function of the native heart to repair the damaged portions of the heart. In this study, whole porcine hearts were decellularized to create a 3D construct that was recellularized with cardiomyocytes (CM) differentiated from human induced pluripotent stem (IPS) cells. At day 4 of differentiation, IPS-derived CMs were implanted onto cardiac extracellular matrix (cECM) and ten …

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Characterization Of Pyrolysis Products From Fast Pyrolysis Of Live And Dead Vegetation, Mohammad Saeed Safdari Dec 2018

Characterization Of Pyrolysis Products From Fast Pyrolysis Of Live And Dead Vegetation, Mohammad Saeed Safdari

Theses and Dissertations

Wildland fire, which includes both planned (prescribed fire) and unplanned (wildfire) fires, is an important component of many ecosystems. Prescribed burning (controlled burning) is used as an effective tool in managing a variety of ecosystems in the United States to reduce accumulation of hazardous fuels, manage wildlife habitats, mimic natural fire occurrence, manage traditional native foods, and provide other ecological and societal benefits. During wildland fires, both live and dead (biomass) plants undergo a two-step thermal degradation process (pyrolysis and combustion) when exposed to high temperatures. Pyrolysis is the thermal decomposition of organic material, which does not require the presence …

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Relationship Between Compressive Strength Of Different Shape And Thickness Specimens Of Type S Mortar, Theodore James Moffett Dec 2018

Relationship Between Compressive Strength Of Different Shape And Thickness Specimens Of Type S Mortar, Theodore James Moffett

Theses and Dissertations

Mortar is the cementitious binding material placed between masonry blocks to create a composite system. The American Society of Testing and Materials (ASTM), along with other organizations, have established the testing of prismatic mortar specimens for evaluating mechanical properties, like compressive strength. Mortar joints, however, possess vastly different characteristics compared to prismatic specimens, especially in terms of geometry and water content. These differences prevent a direct comparison of compressive strength between prismatic specimens and actual mortar joints in the assembly. The objective of this study was to analyze Type S mortar joints, with particular emphasis on specimen shape and water …

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Experimental Evaluation Of Replaceable Shear Fuse Moment Connections, Shannon Shun Oh Dec 2018

Experimental Evaluation Of Replaceable Shear Fuse Moment Connections, Shannon Shun Oh

Theses and Dissertations

Steel special moment frames (SMFs) are known to be highly ductile seismic force- resisting systems. The performance of an SMF relies on the ability of the connections to accommodate large inelastic deformations. After the brittle failure of some steel moment frame connections during the 1994 Northridge Earthquake, experimental tests were used to investigate the ductility and strength of these connections. An experimental study was performed to investigate the seismic performance a new connection called the Replaceable Shear Fuse (RSF) connection. The RSF connection uses shear-yielding fuse plates to prevent beam and column yielding. A total of 7 test specimens with …

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Internal Deformation Measurements And Optimization Of Synthetic Vocal Fold Models, Cassandra Jeanne Taylor Dec 2018

Internal Deformation Measurements And Optimization Of Synthetic Vocal Fold Models, Cassandra Jeanne Taylor

Theses and Dissertations

Developing lifelike vocal fold models is challenging due to various associatedbiomechanical complexities. Nevertheless, the development and analysis of improved vocal foldmodels is worthwhile since they are valuable tools for gaining insight into human vocal foldvibratory, aerodynamic, and acoustic response characteristics. This thesis seeks to contribute tothe development of computational and physical vocal fold modeling in two ways. First is byintroducing a method of obtaining internal deformation fields within vibrating synthetic vocal foldmodels; second is by presenting an optimization algorithm coupled with a computational vocalfold model to optimize geometry and stiffness of a synthetic vocal fold model to achieve morerealistic vibration …

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The Effects Of Haptics On Rhythm Dance Game Performance And Enjoyment, Bridger Scott Hodges Dec 2018

The Effects Of Haptics On Rhythm Dance Game Performance And Enjoyment, Bridger Scott Hodges

Theses and Dissertations

Haptics are an exciting, ever-expanding field, particularly in relation to video games. Though haptics found their way rather quickly into conventional games through devices like handheld controllers, music and rhythm titles have hardly seen such attention. Little research has been done to examine the effects of haptics on rhythm dance games from a quantitative and qualitative standpoint for the player. StepMania is an open-source dance game which closely mimics the popular title Dance Dance Revolution. This research investigates the effects of haptics on a sample size of fifty individuals. Each completed three songs in the game with varying conditions: the …

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Origami-Based Design Of Fold States And Stability, Alex Avila Dec 2018

Origami-Based Design Of Fold States And Stability, Alex Avila

Theses and Dissertations

Origami is a potentially elegant and powerful source of inspiration for many engineering designs. The viable shapes (fold states) of a single device allow it to perform multiple, seemingly contradictory, functions. The fold state is a large factor in the device's performance, but there are challenges in selecting and maintaining those fold states. In this thesis we analyze existing concepts for overcoming these challenges. Those concepts are compared with those that occur in origami-based devices. From this analysis fundamental gaps were identified, specifically, shortcoming in the terminology used to refer to (1) non-flat origami states and (2) sets of facets …

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Examining The Mechanics Responsible For Strain Delocalization In Metallic Glass Matrix Composites, Casey Owen Messick Dec 2018

Examining The Mechanics Responsible For Strain Delocalization In Metallic Glass Matrix Composites, Casey Owen Messick

Theses and Dissertations

Metallic glass matrix composites (MGMCs) have been developed to improve upon the ductility of monolithic metallic glass. These composites utilize a secondary crystalline phase that is grown into an amorphous matrix as isolated dendritic trees. This work seeks to understand the mechanisms underlying strain delocalization in MGMCs in order to better direct efforts for continual progress in this class of material. A mesoscale modelling technique based on shear transformation zone (STZ) dynamics is used to do so. STZ dynamics is a coarse grained technique that can provide insight into the microscopic processes that control macroscopic behavior, but which can be …

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The Design, Construction, And Thermal Diffusivity Measurements Of The Fluorescent Scanning Thermal Microscope (Fstm), Samuel Hunter Hayden Dec 2018

The Design, Construction, And Thermal Diffusivity Measurements Of The Fluorescent Scanning Thermal Microscope (Fstm), Samuel Hunter Hayden

Theses and Dissertations

Over the life of nuclear fuel, inhomogeneous structures develop, negatively impacting thermal properties. New fuels are under development, but require more accurate knowledge of how the properties change to model performance and determine safe operational conditions. Measurement systems capable of small–scale, pointwise thermal property measurements and low cost are necessary to measure these properties and integrate into hot cells where electronics are likely to fail during fuel investigation. This project develops a cheaper, smaller, and easily replaceable Fluorescent Scanning Thermal Microscope (FSTM) using the blue laser and focusing circuitry from an Xbox HD-DVD player. The FSTM also incorporates novel fluorescent …

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Using Non-Destructive Testing To Predict Bending Modulus Of Carbon Infiltrated-Carbon Nanotubes, Fred Stile Fagergren Dec 2018

Using Non-Destructive Testing To Predict Bending Modulus Of Carbon Infiltrated-Carbon Nanotubes, Fred Stile Fagergren

Theses and Dissertations

Fabrication of carbon infiltrated carbon nanotubes (CI-CNT) can result in large mechanical property variation, and methods to characterize properties usually involve destructive testing. Finding a non-destructive way to test for stiffness of this material reduces the number of parts that have to be made. It also simplifies testing of complex parts. The stiffness of CI-CNT beams is related to the type of carbon material infiltrated between the carbon nanotubes (CNTs), how it interacts with the CNTs, and how much of it there is. The amount of material can be estimated using the density of the beam, and both the type …

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