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Articles 42691 - 42720 of 196433

Full-Text Articles in Engineering

Synthesis, Characterization And Tribological Properties Of Mo-Dlc, Tirth Ashishbhai Patel Dec 2021

Synthesis, Characterization And Tribological Properties Of Mo-Dlc, Tirth Ashishbhai Patel

Material Science and Engineering Theses - Archive

Diamond like carbon (DLC) films have been extensively used in a wide range of applications over the last decade due to their excellent mechanical and tribological properties. Metallic elements are used to dope DLC films in an effort to overcome some DLC limitations and make it compatible to use it in larger variety of applications. This study focuses on the effect of different processing parameters on DLC deposition, and the effect of Mo content on microstructure, mechanical and tribological properties. Plasma Enhanced Chemical Vapor Deposition (PECVD) technique coupled with magnetron sputtering is used in chamber atmosphere composed of CH4 and …


A Numerical Study Of Water Entry Problems Based On Overset Meshes, Yanni Chang Dec 2021

A Numerical Study Of Water Entry Problems Based On Overset Meshes, Yanni Chang

Mechanical and Aerospace Engineering Dissertations - Archive

A series of numerical experiments carried out on the water entry of circular cylinders are presented in this study. A cylinder was entering into the water with a prescribed inclined angle and velocity. The interface between water and air is tracked by the Piecewise Linear Interface Calculation (PLIC) schemes in conjunction with the Volume of Fluid (VOF) method. PLIC schemes have been extensively employed in the VOF method for interface capturing in numerical simulations of multiphase flows. Dynamic overset meshes, which have been widely used for problems with relative motions and complex geometric shapes, are applied to handle the moving …


Characterization And Enhancement Of Fatigue And Fracture Properties In Thermoplastic Fff Parts Using In-Situ Annealing, Manjarik Mrinal Dec 2021

Characterization And Enhancement Of Fatigue And Fracture Properties In Thermoplastic Fff Parts Using In-Situ Annealing, Manjarik Mrinal

Mechanical and Aerospace Engineering Dissertations - Archive

Fused filament fabrication (FFF) show high anisotropy and reduced mechanical properties as compared to conventional manufacturing techniques. This happens due to the poor interlaminar bonding between the layers, as a result of premature halt of bond healing process. Previous research works show multiple approaches to improve the bond quality to enhance the mechanical properties of FFF parts, however these are complex and expensive techniques. In this work a novel print head assembly is presented to offer a simple and effective solution by applying a thermal field to the part as it is being printed to preheat the previously deposited layer, …


Internal Pressure Response Of A Human Head Surrogate Model Subject To Variable Impact Loading With Finite Element Analysis, Aaron Ronald Jackson Dec 2021

Internal Pressure Response Of A Human Head Surrogate Model Subject To Variable Impact Loading With Finite Element Analysis, Aaron Ronald Jackson

Mechanical and Aerospace Engineering Theses - Archive

Traumatic brain injury (TBI) from blunt impacts to the head is a major cause of brain disease and dysfunction for thousands of people every year. Each year in the United States approximately 1 million TBI cases occur causing as many as 56,000 deaths and leaving nearly 90,000 individuals with long-term disabilities. Damage resulting from a TBI occurs on a multiscale level including the macroscopic, tissue, and neuron length scale. This research focuses on correlating the macroscopic blunt impact conditions to the internal pressure developed in the coup and countercoup for water and gelatin-filled head models. Two separate 3D printed models …


Synthesis And Characterization Of Graphene-Reinforced Polymer Filaments For Additive Manufacturing, Sean Menezes Dec 2021

Synthesis And Characterization Of Graphene-Reinforced Polymer Filaments For Additive Manufacturing, Sean Menezes

Mechanical and Aerospace Engineering Theses - Archive

Fused Deposition Modeling (FDM) is a popular 3D printing process which uses a spool of thermoplastic polymer filament that is melted by the movable extruder printer head onto the bed to generate the required shape. The most used polymer filaments in FDM are Acrylonitrile Butadiene Styrene (ABS) and Poly Lactic Acid (PLA). However, these conventional polymer filaments have lower mechanical strength and are more susceptible to cracking as the cooler parts of the printed part shrink so much that they cause cracks to develop, leading to warping. The current investigation focuses on the synthesis of graphene, synthesis of polymer filaments …


Reverse Engineering To Create High Quality Polymer Parts Using Additive Manufacturing, Gurtej Singh Tarsem Singh Channa Dec 2021

Reverse Engineering To Create High Quality Polymer Parts Using Additive Manufacturing, Gurtej Singh Tarsem Singh Channa

Mechanical and Aerospace Engineering Theses - Archive

Reverse engineering is a process of recreating parts for which the tools no longer exist, reducing the cost of an original part by manufacturing it in-house or redesigning and improving the original part's function. This research demonstrates two methods to reverse engineer a part using Polyworks software, having it printed using an SLS printer and checking the accuracy of the printed part to the original scan. The part is first scanned using a Faro-Arm laser scanner to obtain the point cloud data. The two methods used to recreate and extract the STEP file are: • Exporting NURBS. • Exporting Features …


Development Of The Vehicle Configuration Compendium: A Comprehensive Data-Information-Knowledge System To Aid In High-Speed Vehicle Design, Stenila Simon Dec 2021

Development Of The Vehicle Configuration Compendium: A Comprehensive Data-Information-Knowledge System To Aid In High-Speed Vehicle Design, Stenila Simon

Mechanical and Aerospace Engineering Theses - Archive

The conceptual design phase is the most crucial phase in hypersonic vehicle design. Choices made during this phase will have significant impact on the success of the overall project and the feasibility of the end-product. Therefore, it is of utmost importance for the design decision-maker to be adequately informed of past-to-present projects throughout the aerospace community and lessons learned from them. This avoids wasting valuable time and resources for reinventing the wheel. There currently exists no one-stop solution in the aerospace industry to address the issue of lost data, information and knowledge in the field of high-speed vehicle design. The …


Relating Linear And Rotational Accelerations With Internal Pressures Developed Inside Human Head Surrogate Models, Arthur Thomas Koster Dec 2021

Relating Linear And Rotational Accelerations With Internal Pressures Developed Inside Human Head Surrogate Models, Arthur Thomas Koster

Mechanical and Aerospace Engineering Theses - Archive

Traumatic Brain Injury (TBI) is a chronic disease process that is difficult to both detect and treat. TBI can result from blast, kinetic, sonic, and electromagnet energy sources. This research focuses on correlating the bulk acceleration of a human-like head model to the localized internal pressure developed in the coup and contrecoup regions due to variable impact loading. Damage resulting in a TBI occurs on a multiscale level from the macroscale down to the damage of each individual neuron. Obtaining a relationship between bulk acceleration and localized internal pressure will allow for further correlation to the damage done on these …


Investigation Of Heat Transfer Performance Of Double Pipe Counter-Flow Heat Pipe Using Three Fluids Water, Dowtherm, And Water-Based Nanofluid, Alaa Abed Harchan Al Hasseun Dec 2021

Investigation Of Heat Transfer Performance Of Double Pipe Counter-Flow Heat Pipe Using Three Fluids Water, Dowtherm, And Water-Based Nanofluid, Alaa Abed Harchan Al Hasseun

Mechanical and Aerospace Engineering Theses - Archive

Heat pipes are two-phase devices, capable of converting a significant amount of energy with low losses. They have been used in several applications such as systems thermal control and cooling. The purpose of the present work is to investigate the thermal performance of a double pipe counterflow against the fluid type. The pipe is divided into three zones including evaporator, adiabatic, and condenser zones. All thermal boundary conditions are defined in terms of heating or cooling temperatures in which the operating temperatures are defined between 303 K to 470 K. using Ansys Fluent, the pipe is analyzed in two-and three-dimensional …


Prediction Of Solder Joint Fatigue Life Of Photonic Package Using ?-? Materials, Ojas Tyagi Dec 2021

Prediction Of Solder Joint Fatigue Life Of Photonic Package Using ?-? Materials, Ojas Tyagi

Mechanical and Aerospace Engineering Theses - Archive

Fatigue life prediction has become very important factor in reliability of any electronic components to withstand extreme thermal stresses in industrial standard. Hence, photonic packages are widely used in telecommunication and computer applications. The primary focus of this study is to determine the thermal cycles to crack initiation of solder bump used in laser array waferboard for telecommunication applications. This includes GaAs Laser chip on waferboard and Si substrate with pure Indium solder balls in between. Indium has proved higher fatigue life in various experimental studies in the field of reliability and lead-free material. Therefore, a solder ball was designed …


Analysis Of Blood Pressure Waveform For Detection And Diagnosis Of Cardiovascular Anomalies, Atul Shrotriya Dec 2021

Analysis Of Blood Pressure Waveform For Detection And Diagnosis Of Cardiovascular Anomalies, Atul Shrotriya

Mechanical and Aerospace Engineering Theses - Archive

Cardiovascular diseases are the leading cause of mortalities worldwide as well as in the United States. Early diagnosis and prediction of these diseases is critical to mitigate the risks to the patient. A common method to assess a person’s heart health is through the use of cuff type oscillometric devices placed on the arm of the patient. As the mean pressure in the cuff is increased the blood flow in the brachial artery becomes blocked. When the cuff pressure is reduced the blood starts flowing again; during this cycle, pressure fluctuations in the cuff are measured using a pressure transducer. …


Determination Of Guidance Laws For Uav Systems In Communication Networks Using Collision Cone Theory, Utsav Mudgal Dec 2021

Determination Of Guidance Laws For Uav Systems In Communication Networks Using Collision Cone Theory, Utsav Mudgal

Mechanical and Aerospace Engineering Theses - Archive

Unmanned Aerial Vehicles (UAVs), also commonly known as drones, are used in various applications, including military applications such as surveillance and intelligence-gathering as well as civilian applications such as search and rescue. The use of UAVs to form communication networks is a topic of active research interest. This thesis aims to investigate the development of guidance laws for multiple UAVs to form such communication networks. Toward this end, this thesis employs tools from collision cone theory and incorporates them with parameters used to describe a communication network. Different types of networks are evaluated for use of the guidance laws. Simulation …


Guidance Laws For N-Mobile Agents To Grip A Moving Target, Pranay Gadiya Dec 2021

Guidance Laws For N-Mobile Agents To Grip A Moving Target, Pranay Gadiya

Mechanical and Aerospace Engineering Theses - Archive

In this thesis, we consider the problem of n mobile agents carrying a gripper, with the objective of gripping a moving circular target. The target may move with constant velocity, or even maneuver. We develop guidance laws by which the agents can first cage the target and subsequently grip it. These guidance laws are developed based on a collision cone framework, using which the mobile agents cooperatively steer their velocity vectors in an appropriate fashion to meet their objective. It is assumed that each of the mobile agents are equipped with a lidar sensor, using which they obtain the range …


Effects Of Il-10 On Local Cell Populations And Functional Recovery Following Vml Injury, Zain Blackwell Dec 2021

Effects Of Il-10 On Local Cell Populations And Functional Recovery Following Vml Injury, Zain Blackwell

Biomedical Engineering Undergraduate Honors Theses

Volumetric muscle loss (VML) injuries are prevalent in both military personnel suffering from battlefield related incidents, and civilians following severe motor accidents. Despite its prevalence, VML has no pro-regenerative clinical treatments in place to recover some of the functional capabilities of the damaged muscle. Free flap grafting, debridement of damaged tissue, and physical therapy are the only clinical standards available that offer little functional recovery benefits, even after years of consistent treatment. In this study, anti-inflammatory cytokine interleukin-10 in conjunction with autologous minced muscle was assessed as a possible treatment for VML injuries and its influences on cellular behavior within …


Buckling Load Optimization Of Variable Stiffness Composite Plate Using Fem And Semi-Analytical Method, Jeegar Vallabhbhai Patel Dec 2021

Buckling Load Optimization Of Variable Stiffness Composite Plate Using Fem And Semi-Analytical Method, Jeegar Vallabhbhai Patel

Mechanical and Aerospace Engineering Theses - Archive

The advent of new composite manufacturing techniques like Automated Fiber Placement (AFP) offers greater flexibility in structural designs by allowing curvilinear fiber paths. Hence, it is now possible to change laminate stiffness locally, thereby enabling Variable Stiffness (VS) composite structures. Such structures demonstrate superior buckling performance over traditional constant stiffness structures. However, obtaining the optimum fiber paths to improve buckling performance remains an open area of research due to the complexity of determining such fiber paths. This research investigated two approaches for optimizing fiber paths; First, a Finite Element Method (FEM) approach that utilizes linear shape functions to interpolate local …


A Modular Platform For Intrusive Diagnostics And Tps Testing In The Onr-Uta Arc-Jet Facility, Blake Anthony Hamilton Dec 2021

A Modular Platform For Intrusive Diagnostics And Tps Testing In The Onr-Uta Arc-Jet Facility, Blake Anthony Hamilton

Mechanical and Aerospace Engineering Theses - Archive

This work presents an approach to the design, and successful experimental implementation, of a modular platform for intrusive diagnostics and TPS testing in the ONR-UTA Arc-Heated Wind Tunnel "Leste" Facility. The harsh conditions typical of arc-jet facilities (hypersonic, high-enthalpy, chemically-reacting, continuous flows) present a challenge to the design of insertion platforms. In this work a detailed analysis of the aerothermal loads is used to aid in the design process. Specific design points for this modular platform and its ancillary instrumentation have been identified. Based on this design approach, a modular platform for intrusive diagnostics and TPS testing has been developed. …


The Effects Of Snagcu Solder Interconnect Package’S Parameters On Electromigration Failure Mechanisms, Yi Ram Kim Dec 2021

The Effects Of Snagcu Solder Interconnect Package’S Parameters On Electromigration Failure Mechanisms, Yi Ram Kim

Material Science and Engineering Dissertations - Archive

The primary concern of this dissertation is the electromigration (EM) failure mechanism found in Sn-Ag-Cu (SAC) solder alloys integrated in WCSP (wafer-level chip scale package) packaging structure and factors affecting the failure mechanisms. To the end, accelerated electromigration (EM) tests are conducted on SnAgCu (SAC) solder interconnects in wafer-level chip scale packages (WCSPs or WLCSPs) with different package structures and use-condition parameters. The package structure parameters include different under bump metallization (UBM) thicknesses, Sn grain orientation, while the various in use conditions includes pulsed direct current (DC), and alternating current (AC). The major findings made in the studies are presented …


Plasma Electrolytic Oxidation Of Pure Titanium At Constant Applied Voltage, Hunter Pitts Dec 2021

Plasma Electrolytic Oxidation Of Pure Titanium At Constant Applied Voltage, Hunter Pitts

Material Science and Engineering Theses - Archive

Plasma Electrolytic Oxidation (PEO) is a method of coating which is used to apply non metal coatings to different metal substrates. This process occurs in an electrochemical cell that consists of an electrolyte, two electrodes submerged in the electrolyte and a power supply supplying voltage to the two electrodes. The goal of this study was to observe how a constant applied voltage would affect the coating thickness at varied applied voltage and varied processing time. This study was a continuation of a constant applied voltage study previously performed in the SaNEL research group. It was continued to add more detailed …


Role Of Binder Compositions And Carbonate Polymorphs On The Performance Of Carbonation Activated Cementitious Composites, Mohammad Rakibul Islam Khan Dec 2021

Role Of Binder Compositions And Carbonate Polymorphs On The Performance Of Carbonation Activated Cementitious Composites, Mohammad Rakibul Islam Khan

Civil Engineering Dissertations - Archive

The most energy-intensive manufacturing industry in the US is the Ordinary Portland Cement (OPC) industry. This industry is responsible for 5-8% of global CO2 emissions caused by humans. The calcination of limestone to produce high lime calcium silicate and high manufacturing temperature (1450°C) are responsible for this significant amount of CO2 emissions. This CO2 footprint of the cement-based composites can be decreased by utilizing cementitious materials with low-lime calcium silicate. Low-lime calcium silicates are typically semi-hydraulic or non-hydraulic. As a result, it is necessary to activate those materials in order to increase their reactivity. Alkali activators, carbonation curing (CO2 curing), …


Rainfall-Induced Slope Failure – An Early Warning System, Md Aminul Islam Dec 2021

Rainfall-Induced Slope Failure – An Early Warning System, Md Aminul Islam

Civil Engineering Dissertations - Archive

Globally, slope failures cause substantial death tolls and economic loss. Embankments constructed on high plasticity clay are vulnerable to cyclic swelling and shrinkage when subjected to climate. Thus, over time, soil softens and reduces effective shear strength, and shrinkage cracks on slopes can act as pathways for rainfall infiltration, which increases pore water pressure and lowers the shear strength below critical levels, resulting in slope failure. This study aims to develop early warning criteria for rainfall-induced slope failure. Study areas were Tarrant, Dallas, Johnson, and Ellis, where soil types and a humid subtropical climate result in frequent slope failures. The …


Designing And Advancing Contrast Agents For Ultrasound-Switchable Fluorescence Imaging, Yang Liu Dec 2021

Designing And Advancing Contrast Agents For Ultrasound-Switchable Fluorescence Imaging, Yang Liu

Bioengineering Dissertations - Archive

Fluorescence imaging is a remarkable tool for molecular targeting and multicolor imaging, but it suffers from poor resolution in centimeters-deep tissues. The recently developed ultrasound-switchable fluorescence (USF) imaging has overcome this challenge and achieved in vivo imaging with the help of the indocyanine green (ICG)-encapsulated poly(N-isopropylacrylamide) (ICG-PNIPAM) contrast agent. As USF imaging advances, there is a great demand to expand the contrast agent bank so that applications can be achieved using different types of contrast agents. Also, there is a need to improve the current ICG-PNIPAM nanogel. This study focused on improving the ICG-PNIPAM nanogel, formulating a novel contrast agent, …


Assessment Of Stormwater Infrastructure For Mitigating Flooding And Non-Point Source Pollution, Helia Farzaneh Dec 2021

Assessment Of Stormwater Infrastructure For Mitigating Flooding And Non-Point Source Pollution, Helia Farzaneh

Civil Engineering Theses - Archive

Flooding is the top natural hazard impacting coastal and inland communities in Texas. Beyond its destructive impact on rising waters in communities, flooding-induced stormwater negatively affects the quality of large bodies of water. Stormwater runs over land, washes off pollutants, and deposits them into rivers which causes water quality issues in bays and estuaries. In addition, the stormwater increases nutrients, sediments, oxygen-demanding substances, pathogens, and toxins which results in hypoxia in the aquatic system. During the last 5-6 years, severe storm events such as Tropical Storm Beta (September 2020), Tropical Storm Imelda (September 2019), Hurricane Harvey (August 2017) have caused …


Fire Performance Of Hybrid Fiber Reinforced Self-Consolidating Concrete (Hfrscc) With Glass Pozzolan, Rishabh Kumar Dec 2021

Fire Performance Of Hybrid Fiber Reinforced Self-Consolidating Concrete (Hfrscc) With Glass Pozzolan, Rishabh Kumar

Civil Engineering Theses - Archive

This research focuses on the effects of hybridizing self-consolidating concrete (SCC) using steel (SF) and polypropylene (PP) fibers to study their benefits post-fire exposure. In an attempt to reduce cement’s environmental impacts and to make concrete more sustainable, this research also studies the substitution of cement using glass pozzolan. Limited research has been done in this regard previously, hence this research makes an effort to bridge the enormous knowledge gap. No research has reported tensile, compressive, and flexural strength of SCC with hybrid fibers and glass pozzolan, making this research unique. Based on previous research, the replacement rate of cement …


Performance Evaluation And Retrofitting Options For An Impact Damaged Non-Composite Steel Girder Bridge, Mohd Mezanur Rahman Dec 2021

Performance Evaluation And Retrofitting Options For An Impact Damaged Non-Composite Steel Girder Bridge, Mohd Mezanur Rahman

Civil Engineering Dissertations - Archive

The Federal Highway Administration (FHWA) has rated about 32% of total bridges in US as structurally deficient or functionally obsolete. One of the most frequently encountered issues for this deficiency is the impact created by cars that exceed the posted clearance for a bridge. Impact damage leads to concrete spalling or cracking, exposed or broken reinforcement/prestressing strands, global and local buckling of the structural member or piercing through the steel girder. For Example, St. Francis Bridge (North Bound) carrying St. Francis Avenue over I-30 east of downtown Dallas was impact damaged by an eighteen-wheeler carrying a heavy-duty wrecker on 29th …


Active Compensation Of Radiation Effects On Optical Fibers For Sensing Applications, Sohel Rana, Austin Fleming, Nirmala Kandadai, Harish Subbaraman Dec 2021

Active Compensation Of Radiation Effects On Optical Fibers For Sensing Applications, Sohel Rana, Austin Fleming, Nirmala Kandadai, Harish Subbaraman

Electrical and Computer Engineering Faculty Publications and Presentations

Neutron and gamma irradiation is known to compact silica, resulting in macroscopic changes in refractive index (RI) and geometric structure. The change in RI and linear compaction in a radiation environment is caused by three well-known mechanisms: (i) radiation-induced attenuation (RIA), (ii) radiation-induced compaction (RIC), and (iii) radiation-induced emission (RIE). These macroscopic changes induce errors in monitoring physical parameters such as temperature, pressure, and strain in optical fiber-based sensors, which limit their application in radiation environments. We present a cascaded Fabry–Perot interferometer (FPI) technique to measure macroscopic properties, such as radiation-induced change in RI and length compaction in real time …


A Multi-Dimensional Child-Langmuir Law For Any Diode Geometry, N. R. Sree Harsha, Marcus Pearlman, Jim Browning, Allen L. Garner Dec 2021

A Multi-Dimensional Child-Langmuir Law For Any Diode Geometry, N. R. Sree Harsha, Marcus Pearlman, Jim Browning, Allen L. Garner

Electrical and Computer Engineering Faculty Publications and Presentations

While prior theoretical studies of multi-dimensional space-charge limited current (SCLC) assumed emission from a small patch on infinite electrodes, none have considered emission from an entire finite electrode. In this paper, we apply variational calculus (VC) and conformal mapping, which have previously been used to derive analytic solutions for SCLC density (SCLCD) for nonplanar one-dimensional geometries, to obtain mathematical relationships for any multi-dimensional macroscopic diode with finite cathode and anode. We first derive a universal mathematical relationship between space-charge limited potential and vacuum potential for any diode and apply this technique to determine SCLCD for an eccentric spherical diode. We …


Attenuation Of Several Common Building Materials: Millimeter-Wave Frequency Bands 28, 73, And 91 Ghz, Mahfuza Khatun, Changyu Guo, Hani Mehrpouyan Dec 2021

Attenuation Of Several Common Building Materials: Millimeter-Wave Frequency Bands 28, 73, And 91 Ghz, Mahfuza Khatun, Changyu Guo, Hani Mehrpouyan

Electrical and Computer Engineering Faculty Publications and Presentations

Future cellular systems will make use of millimeter-wave (mm-wave) frequency bands. Many users in these bands are located indoors, i.e., inside buildings, homes, and offices. The typical building material attenuations in these high-frequency ranges are of interest for link budget calculations. In this article, we report on a collaborative measurement campaign to find the attenuation of several typical building materials in three potential mm-wave bands (28, 73, and 91 GHz). Using directional antennas, we took multiple measurements at multiple locations using narrow-band and wideband signals and averaged out residual small-scale fading effects. The materials include clear glass, drywall (plasterboard), plywood, …


Respiratory Sound Analysis For The Evidence Of Lung Health, Priyanka Sreerama Dec 2021

Respiratory Sound Analysis For The Evidence Of Lung Health, Priyanka Sreerama

Dissertations and Theses

Significant changes have been made on audio-based technologies over years in several different fields along with healthcare industry. Analysis of Lung sounds is a potential source of noninvasive, quantitative information along with additional objective on the status of the pulmonary system. To do that medical professionals listen to sounds heard over the chest wall at different positions with a stethoscope which is known as auscultation and is important in diagnosing respiratory diseases. At times, possibility of inaccurate interpretation of respiratory sounds happens because of clinician’s lack of considerable expertise or sometimes trainees such as interns and residents misidentify respiratory sounds. …


Distributed And Optimal State Estimation For Heterogeneous Dynamic Systems Operating Within A Strongly Connected Network, Matthew Howard Dec 2021

Distributed And Optimal State Estimation For Heterogeneous Dynamic Systems Operating Within A Strongly Connected Network, Matthew Howard

Electronic Theses and Dissertations, 2020-2023

This dissertation is aimed at developing optimal and distributed state estimation algorithms for a team of cooperating nodes with the goal of improving accuracy through local sharing of relevant information. The nodes are assumed to be individually equipped with heterogeneous sensors for measuring a common target which can be dynamic and time-varying. Additionally, the nodes are assumed to be connected through a dynamically changing communication network modeled as a sequence of strongly connected digraphs allowing for local communication and distributed interactions. Using the data sharing afforded by the communication network, a weighted average state estimate consensus can be found across …


Investigation Into Wedge Turbulator Effects In High Aspect Ratio Cooling Channels, Daniel Garcia Dec 2021

Investigation Into Wedge Turbulator Effects In High Aspect Ratio Cooling Channels, Daniel Garcia

Electronic Theses and Dissertations, 2020-2023

With reusability being a novel design parameter for liquid rocket engines (LRE), the need to lower internal wall temperatures for an increased engine longevity is a desired outcome. One of the mechanisms that has been effectively implemented is the use of high aspect ratio cooling channels (HARCC) to promote fin-like effects from internal cooling channel sidewalls. In the gas turbine industry, the use of wedge turbulators has gained recognition for its heat augmentation properties with relatively low pressure drop penalty. In an ideal case, LRE's could adopt the wedge turbulator cooling technique to enhance the benefits of HARCC with minimal …