Engineering Commons^™

Computational Investigation Of Impingement Cooling For Regeneratively Cooled Rocket Nozzles, Bianca A. De Angelo

Doctoral Dissertations and Master's Theses

Jet impingement cooling is an internal cooling configuration used in the thermal management of temperature sensitive systems. With rocket engine combustion temperatures rising as high as 3600 K, it is essential for a cooling method to be applied to ensure that the nozzle integrity can be maintained. Therefore, a novel heat transfer study is conducted to investigate if jet impingement cooling is feasible for a regenerative cooling rocket nozzle application. Regenerative cooling for liquid propellant rockets has been widely studied. However, to the best of the author’s knowledge, there is currently no literature describing this method in conjunction with impingement …

Investigation Of Pin Fin Cooling Channels For Applications In Gas Turbines, Royce Fernandes

Doctoral Dissertations and Master's Theses

Gas turbine blades are often cooled using internal cooling channels to prevent failure at temperatures beyond material limitations. Pin fin channels are commonly used on the trailing edge of the blades, where they enhance heat transfer and also provide structural support. This study focuses on the validation of several commercially available RANS turbulence models in CFD, that are used to computationally simulate the flow features inside a pin fin cooling channel. Turbulence models investigates are: Menter’s kω SST, realizable k-ε, and a quadratic formulation of the realizable k-ε model. The geometry investigated is a staggered 8 row pin fin channel. …

The Effect Of Axial Spacing Of Constant And Variable Blockages On The Deflagration-To-Detonation Transition In A Pulse Detonation Engine, Nicole Gagnon

Doctoral Dissertations and Master's Theses

An investigation was conducted into the effects of obstacle spacing on the deflagration-to-detonation transition section length in a pulse detonation engine. Testing was conducted with one hundred and ninety-five different obstacle, and spacing configurations. The configurations included constant, as well as variable spacing between obstacles. The goal of this investigation was to correlate the spacing between obstacles and the blockage ratio of the obstacles with the detonation success and the shortening of the DDT section. The ten cases that achieved the highest percentage of detonations were investigated further to determine the distance needed for the deflagration-to-detonation transition. A 33% blockage …

Optical Tracking And Spectral Characterization Of Cubesats For Operational Missions, Forrest Gasdia

Doctoral Dissertations and Master's Theses

Orbital debris in low Earth orbit is of growing concern to operational satellites from the government and commercial sector. With an uptick in worldwide satellite launches and the growing adoption of the CubeSat standard, the number of small objects in orbit are increasing at a faster pace than ever. As a result, a cascading collision event seems inevitable in the near future.

The United States Strategic Command tracks and determines the orbit of resident space objects using a worldwide network of radar and optical sensors. However, in order to better protect space assets, there has been increased interest in not …

Vibration Analysis Of A Composite Wing Box With Arbitrarily Shaped Spars And Ribs, Rossana R. Fernandes

Doctoral Dissertations and Master's Theses

In this research, the free vibration analysis of composite wing boxes with curvilinear spars and ribs is performed. Modern manufacturing technologies, such as Electron Beam Freeform Fabrication and Friction Stir Welding, have allowed the manufacturing of arbitrarily shaped stiffeners. Curvilinear stiffeners provide flexibility in design as they can assume an infinite number of paths. Curvilinear spars and ribs can in some instances provide a better vibration and static response than their straight counterparts while reducing the overall mass of the structure. An equivalent continuum plate model of a wing box using energy formulations is proposed at the preliminary design stage …

An Experimental Study Of Synthetic Jet Actuators With Application In Airfoil Lco Control, Sanjay Krishnappa

Doctoral Dissertations and Master's Theses

An experimental study on the development and implementation of Synthetic Jet Actuators (SJAs) is conducted for eliminating aeroelastic phenomenon such as Limit Cycle Oscillations (LCO). One of the biggest challenges involved in the design of UAVs operating in unsteady atmosphere conditions is the susceptibility of the airframe to aeroelastic instabilities, such as flutter or LCO. Suppression of such instabilities can be achieved through the implementation of Active Flow Control (AFC) techniques, however to this day, a limited amount of experimental studies exist. Thus, the focus of this work is to develop a new AFC method consisting of an actuator that …

Mechanical And Electrical Characterization Of Hybrid Carbon Nanotube Sheet-Graphene Nanocomposites For Sensing Applications, Jiukun Li

Doctoral Dissertations and Master's Theses

The unique mechanical and electrical properties of carbon nanotubes and graphitic structures have drawn extensive attention from researchers over the past two decades. The electro-mechanical behavior of these structures and their composites, in which electrical resistance changes when mechanical deformation is applied facilitates their use in sensing applications.

In this work, carbon nanotube sheet- epoxy nanocomposites with the matrix modified with various contents of coarse and fine graphene nanoplatelets are fabricated. The addition of a secondary filler results in improvements of both electrical and mechanical properties. In addition, with the inclusion of the second filler, change in resistivity with mechanical …

Fluidic Jet Turbulence Generators For Deflagration To Detonation Transition In Pulsed Detonation Combustors, Jarrett E. Lowe

Doctoral Dissertations and Master's Theses

The goal of this study is to establish the dominant flow structure required to effectively accelerate the turbulent deflagration flame front to detonation velocity in the shortest possible distance while using a single Jet in Cross Flow (JICF). Jets in crossflow, depending on orientation and momentum ratio, can induce two types of flow structures that propagate downstream; vortex filaments and turbulent eddies. Vortex flow structures are coherent rotating columns that can persist for a considerable distance before diffusing. Turbulent eddies are characterized as random fluctuations in flow velocity or small pockets of rotation. The test rig used for this study …

Magneto-Rheological Fluid Device As Artificial Feel Force System On Aircraft Control Stick, Vignesh Manoharan

Doctoral Dissertations and Master's Theses

The conventional feel system in any aircraft occupies large space in the cockpit and has complicated designs. The primary objective of this research is to develop an artificial feel force system that can overcome some drawbacks of the current feel force system. A novel feel system using magneto-rheological (MR) fluid is constructed to precisely control the shear stress under the magnetic field. To validate the functionality of the MR artificial feel system, the final system is fabricated and multiple tests are performed to acquire force-velocity characteristics that are compared to the mathematical model derived. In addition, the reference model of …

Study Of Hybrid Magneto-Active Propellant Management Device For Slosh Damping, Leander Paul

Doctoral Dissertations and Master's Theses

Sloshing of liquid upon the application of an external force is a natural phenomenon as the free surface is allowed to move without any constraints. Study of slosh is an ongoing research for many decades and many novel inventions in Propellant Management Devices (PMDs) such as the rigid baffles and elastomeric membranes have been implemented to counteract the free surface effect in both passive and active membrane known as Magneto-Active Propellant Management Device (MAPMD) to actively control the free surface effect and reduce fuel slosh is explored in this research. Being a hybrid membrane, it would initially offer passive resistance …

2d Aeroacoustic Analysis Of Flow In The Flame Trench, Meghan Pokorski

Doctoral Dissertations and Master's Theses

We present here a methodology for using the commercial software ANSYSFLUENT to predict the acoustic field associated with Space-Launch System (SLS). We consider a two-dimensional model of flame deflector, and flame trench. The ANSYS code is then used to simulate the internal flow. Both the steady state case is considered along with other cases where the inflow has a harmonic component. A Ffowcs-Williams Hawking (FWH) surface is then constructed within the computational domain to use the computed flow fluctuations to obtain the acoustic field. The acoustic data was then compared to the experimental data.

When using the ANSYS code for …

Analysis Of A Coupled Micro- And Triple-Impingement Cooling Configuration In The C3x Vane, Chase D. Rossman

Doctoral Dissertations and Master's Theses

This study attempts to improve the trailing edge protection of a turbine vane by incorporating two concepts from the literature. These two concepts are optimized near wall cooling passages and a triple-impingement configuration in the vane trailing edge. Finally this study explores a CFD conjugate analysis based on the Shear Stress Transport k(l) turbulence model. The overall goal is to produce a more effective cooling configuration by studying the effects of the flow and heat transfer of the dual configuration, while keeping the integrity of the turbine vane. Star-CCM+ was utilized to carry out the computational data on a 3-D …

Prediction Of Tonal Acoustic Radiation Due To Feedback-Loop Resonant Interactions In Transitional Airfoils, Seyyed Saman Salehian

Doctoral Dissertations and Master's Theses

The objective to this work is to employ the surface integral methods to study the far-field noise propagation from the flow acoustic resonant interactions of the transitional airfoil. The Potential-Theoretic Method (PTM) as an advancement to traditional Kirchhoff methods is presented. The PTM eliminated the need to calculate the normal derivatives of pressure and an arbitrary Kirchhoff surface can be employed. The numerical procedure to implement the PTM is fairly simple. The formulation and physical assumptions of the approach is reviewed, and the numerical procedure is implemented. Furthermore, the two dimensional formulation of the Ffowcs Williams - Hawkings (FW-H) equation …

Sensing, Actuation, And Embedded Control For A Custom Scr Nitrogen Oxides Emissions Reduction System, Anuj Kalidas Sharma

Doctoral Dissertations and Master's Theses

Diesel engines are the main power source for medium and heavy duty on road vehicles. With the rising standards for mileage of vehicles set by the Corporate Average Fuel Economy and the Environmental Protection Agency, diesel engines should soon be considered in lieu of gas engines. Despite advantages of diesel engines, diesel emissions include harmful gasses like carbon monoxide, nitrogen oxides and particulate matter. Selective Catalytic Reduction (SCR) systems have long been used to reduce diesel emissions from medium to heavy-duty diesel engines. Primary focus of this research effort is the implementation and improvement of a SCR system on light …

Real-Time Optimization Based Power Flow Controller For Energy Consumption And Emissions Reduction In A Parallel Hev, Abdulla Abdulaziz Karmustaji

Doctoral Dissertations and Master's Theses

As the regulations on the fuel economy and emissions standards become higher, Hybrid Electric Vehicles (HEV) are gaining more popularity in the market. HEVs improvements in fuel economy and emissions strongly depend on the energy management strategy. An optimization based power flow controller is presented in this thesis to find the appropriate power split between the Internal Combustion Engine (ICE) and the electric motor to reduce the energy consumption and emissions. However, emissions were not taken into consideration in results due to lack of reliable results. A basic power flow controller was built to compare to the optimization based controller. …

Conversion Of Digital Circuits Labs, Caleb N. Taber

Undergraduate Honors Theses

The engineering technology department at ETSU currently lacks a modern method to teach digital circuits. The aim of this thesis is to convert our current digital circuits labs to equivalent labs suited to run on the Basys 3. The Basys has several advantages over the aging NI Elvis boards (and now just breadboards) currently in use. The first advantage is that the Basys gives students a taste of FPGA programming without being overwhelmingly; like the systems currently in place for the digital signal processing class. The Basys is also a more modern system; our current integrated circuit and breadboard system …

Targeted Drug Delivery Using Peptoid Based Nanospheres, Kaylee J. Smith

Chemical Engineering Undergraduate Honors Theses

While medicine has improved greatly in the last couple of decades, there are negative side effects that accompany many drugs. Undesirable side effects could be greatly reduced if non-systemic drug delivery systems were used because the medicine would harm diseased cells at a much higher rate than it does healthy cells. One possible non-systemic drug delivery system is peptoid nanospheres. These nanospheres will then be linked to another peptoid that is engineered to attach almost exclusively to diseased cells.

This research project is focused on designing peptoids that will form nanospheres in solution. Four specific peptoids were synthesized and tested …

Acceleration Of Ddscat Computation By Parallelization On A Supercomputer, Manoj V. Seeram

Chemical Engineering Undergraduate Honors Theses

The DDSCAT software is enabled for use of MPI or OpenMP to distribute calculation of different particle orientations amongst multiple processors on a high performance system. Run times for these simulations have been tested to take hours or days however and simulating varying orientations is not always necessary. If a simulation with only one particle orientation is submitted, DDSCAT could still potentially parallelize the simulation by wavelength calculations but it is unknown if this is the case. In this paper, we will be (i) quantifying the reduction in computation time that MPI provides relative to an equivalent MPI disabled simulation …

Efficiency And Particulate Matter Emissions Testing Of Wood Burning Heating Units, Andrew J. Casey

Chemical Engineering Undergraduate Honors Theses

For the 2016 WERC/IEE competition, our project regarded the efficiency and particulate matter emissions testing of wood burning heating units. The purpose of the project was to develop a cheap and effective testing method for combustion units in order to decrease manufacturers’ research and development costs. This would ultimately lower the entry barrier to the market and increase the number of manufacturers on the market. This would lead to more efficient stoves being designed and the stoves would be cheaper as a result of the increased competitive market. This would have many benefits on society; the primary benefit being that …

Development Of A Simple Handheld Biosensor For Waterborne Pathogens, Bryce C. Jones

Chemical Engineering Undergraduate Honors Theses

Current methods of detecting waterborne pathogens involve testing strips which take 24-48 hours to yield results, or require expensive equipment in order to function. In minimalist environments, these two technologies are not always applicable to test water quality. With the emergence of a new method of PCR, named LAMP PCR, it is possible to quickly and accurately detect pathogen DNA in a water sample. In order to scale this technique into a simple device, the aspects of the reaction must be accommodated, and a visual detection method chosen. A handheld device which keeps the isothermal LAMP PCR stable for the …

Haul Truck Tires Recycling, Marina E. Lee

Chemical Engineering Undergraduate Honors Theses

The Ball Hogs competed in Task 2 - Haul Truck Tires in the 2016 Waste-Management Education and Research Consortium (WERC) International Environmental Design Contest. This task required designing a solution to recycle discarded haul truck tires from mining sites. Our solution was to use the treads of these haul truck tires to construct liners for ball mills. Recycling haul truck tires in this manner would save the mining companies a substantial amount of money and would result in a decrease of carbon emissions.

Wastewater Reuse, Zachary J. Bare

Chemical Engineering Undergraduate Honors Theses

Approximately 1.2 billion people around the world live in areas of physical water scarcity. This could increase to half of the world’s population by 2030 and could displace 24 to 700 million people unless steps are taken to ensure adequate water supply. Water scarcity is an escalating issue within the United States, specifically in Western inland states with arid climates. This scarcity is encouraging communities to investigate tertiary level municipal wastewater treatment, allowing for reuse of wastewater. Unfortunately, wastewater contains numerous contaminants that are not regulated by the Environmental Protection Agency (EPA) under the Safe Drinking Water Act (SDWA). Many …

Efficiency And Particulate Matter Emissions Testing Of Wood Burning Heating Units, Lindsey Mayo

Chemical Engineering Undergraduate Honors Theses

The performance and use of wood-burning stoves as a heating source is carefully regulated by the Environmental Protection Agency (EPA). The EPA requires a rigorous and exhaustive testing protocol be conducted on each unit before it can be sold commercially in order to ensure that the stove in question will not have a detrimental effect on the surrounding environment. However, this testing routine is incredibly time intensive and costly, resulting in a 90% decrease in the number of stove manufacturers since 1988. This decreased competition has ultimately fostered an industry free from competition and motivation to produce clean and efficient …

Efficiency And Particulate Matter Emissions Testing Of Wood Burning Heating Units, Elisabeth E. Westcott

Chemical Engineering Undergraduate Honors Theses

The Environmental Protection Agency (EPA) is continually revising the regulations on wood-burning units to reduce the particulate matter emissions in the United States. These revisions have caused a large decline in wood-burning stove manufacturers as they bring the need for research and development on current units and small manufacturers cannot burden the large costs. The StoveHogs became aware of this manufacturer decline in the industry and saw an opportunity to help small manufacturers, backyard inventors, and the stove industry as a whole. In order to reduce the costs of research and development on stoves, the StoveHogs designed and tested a …

Investigating The Modulation Of Aggregating Amyloid Beta 40, Marlee J. Motes

Chemical Engineering Undergraduate Honors Theses

Amyloid beta protein has been linked to the formation of Alzheimer’s disease in patients.¹ Plaques form from amyloid beta fibrils. The formation of these plaques between neural connections in the brain are associated with Alzheimer’s disease.² The reduction of the formation of fibrils can be linked to utilizing protein mimics. The protocols that are used to reproduce the simulation of amyloid beta in the brain can be very important. Also, the structure of the protein mimic that is being used to inhibit the formation of fibrils can determine how the amyloid beta plaques are reduced.

The structure of sequence KLLFFLFFLLK …

Peptoid Morphology Studies And Its Performance In Inhibiting Islet Amyloid Polypeptide, Dongwon Park

Chemical Engineering Undergraduate Honors Theses

Abstract 1

Proteins have various arrays of functions in human bodies. The bio-functions of proteins are depend on their amino acid sequences and folding processes that affect protein structure. While most of proteins fold in their own pathways, some of them misfold and aggregate due to mutations caused by various reasons. These aggregations are believed to be main causes of protein conformation disorders like Alzheimer's disease, Type II diabetes, Huntington's disease, and prion disease. An aggregated form of amyloid beta is considered as a hallmark of Alzheimer's disease. Amyloid beta develops from oligomer into a fibril as the aggregation process …

Werc Task #1 - Efficiency And Particulate Matter Emissions Testing Of Wood Burning Heating Units, Jonathan A. Shumaker

Chemical Engineering Undergraduate Honors Theses

A design of a method for calculating the efficiency and particulate matter emission rates was developed for use on wood stoves. The project was completed for the WERC competition which is an international design contest. The prevalence of wood burning as a form of heating, current EPA regulations, and current market conditions were major factors in forming the necessity of this testing method. Design was not limited to outlining the design specifications, the apparatus was built and run. Optimization of the method continued until completion of the project. If the method would continue to be improved then it would be …

Werc Task #1 - Open: Efficiency And Particulate Matter Emissions Testing Of Wood Burning Heating Units, Teni R. Butler

Chemical Engineering Undergraduate Honors Theses

Wood burning has significant environmental and health impacts. This research focused on creating low-cost, reliable test methods for identifying particulate matter emissions to the atmosphere, while obtaining essential data for efficiency calculations of wood combustion.

Stabilization Of Vegetable Oil-Based Quenchants To Thermal-Oxidative Degradation: Experimental Strategy And Effect Of Oxidation On Quenching Performance, Éder Cícero Adão Simêncio, Rosa Lúcia Simêncio Otero, Lauralice De Campos Franceschini Canale, George E. Totten

Mechanical and Materials Engineering Faculty Publications and Presentations

Although petroleum oils continue to be the dominant type of basestock for the formulation of vaporizable quenchants, there is increasing pressure to identify an alternative basestock to address the limitations to their continued use because they are not a renewable basestock and they possess generally poor toxicity and biodegradability properties. Currently the most often cited alternative basestocks are those based on seed oils since they are renewable and usually non-toxic but especially because they are typically readily biodegradable. However, they suffer a critically important deficiency in that they are also typically much less stable to thermal-oxidative degradation than petroleum oils. …

Validation Of An Internal Camera Based Volume Determination System For Triaxial Testing, Leah D. Miramontes

Civil Engineering Undergraduate Honors Theses

Accurate strain and volume measurements are critical to phase relationships and strength determination for saturated and unsaturated soils. In recent years, laboratory-based photographic techniques of monitoring soil specimens have become more common. These techniques have been used to reconstruct 3D models and to determine strain and volumetric changes of triaxial specimens. A new technique that utilized digital photographs of the soil specimen, captured from within a triaxial testing cell, was utilized. Photographs were processed using photogrammetry software to reconstruct 3D models of the soil specimens. By placing camera equipment within the cell, the technique eliminated the need to account for …