Digital Commons Network^™

Electric Solid Propellant Ablation In A Pulsed Electric Thruster, Matthew S. Glascock, Joshua L. Rovey

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Electric solid propellants are advanced solid chemical rocket propellant that can be controlled (ignited, throttled and extinguished) with electric current. Work reported here focuses on application of electric solid propellant in a pulsed electric thruster similar to a pulsed plasma thruster. In the future it may be possible to develop a dual-mode electric solid propellant thruster that is switchable between steady applied electric current chemical mode and pulsed alternating electric current electric mode. Results presented here use a laboratory test thruster to create an arc discharge of 5-20 J per pulse in a cylindrical cavity of propellant. Results for Teflon …

Square-Root Consider Filters With Hyperbolic Householder Reflections, James S. Mccabe, Kyle J. De Mars

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Maintaining positive definiteness of a filter's error covariance estimate is of paramount importance to any stable and reliable estimation scheme. Two widely used methods for protecting a filter from loss of positive-definiteness are that of consider filtering and square-root filtering. Despite their widespread use in estimation applications, a filtering methodology that combines the two techniques has yet to be presented in a unified, streamlined architecture. This paper develops a new approach to square-root filtering using hyperbolic Householder reflections. A specialization of the method is considered to permit computationally efficient applications, and a numerical example pertaining to a ballistic reentry is …

Set-Theoretic Model Reference Adaptive Control Of A Generic Transport Model, Ehsan Arabi, Tansel Yucelen, Nhan T. Nguyen

Mechanical and Aerospace Engineering Faculty Research & Creative Works

This paper illustrates an application of a recently developed set-theoretic model reference adaptive control architecture on a generic transport model developed by NASA. The set- theoretic model reference adaptive control allows the system error bound between the state of an uncertain dynamical system and the state of a given reference model to be less than a-priori, user-defined worst-case performance bound. Thus, it has the capability to enforce strict performance guarantees to the adaptively controlled uncertain dynamical systems. specifically, after designing set-theoretic adaptive controllers for both longitudinal and lateral-directional dynamics here, the efficacy of this architecture is illustrated on the NASA …

Linear Burn Rate Of Monopropellant For Multi-Mode Micropropulsion, Alex J. Mundahl, Steven P. Berg, Joshua L. Rovey

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Multi-mode micro propulsion is a technology that can enable rapidly composable small satellites with unprecedented mission flexibility. To maximize mission flexibility a multi-mode micro propulsion monopropellant must be shared between the chemical and electric propulsion modes. Previous research has identified a promising monopropellant that is both readily catalytically exothermically decomposed (chemical mode) and electro sprayable (electric mode). In this work the linear burn rate of this monopropellant is determined and used to aid the design of a microtube catalytic chemical thruster. Experiments with a pressurized fixed volume reactor are used to determine the linear burn rate. Benchmark experiments use a …

Electrospray Mass Spectroscopy Of A Han-Based Monopropellant, Mitchell J. Wainwright, Joshua L. Rovey, Shawn W. Miller, Benjamin D. Prince, Steven P. Berg

Mechanical and Aerospace Engineering Faculty Research & Creative Works

A mixture of [Emim][EtSO4]-HAN is a potential propellant suitable in a multi-mode chemical-electric microtube-electrospray micro propulsion system. This paper reports experimental mass spectrum results for this liquid when electro sprayed in a 50 μm capillary emitter. Mass spectra from 0-600 amu were obtained over a variety of angles and flow rates from 2 pL/sec to 3 nL/sec in both cation and anion extraction mode. Effects of flow rate and angular orientation on the spectra agree well with literature. Results show at least three of the four monomer species are emitted, along with numerous other species, some of which have been …

Review Of Metal Am Simulation Validation Techniques, Aaron Flood, Frank W. Liou

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Due to the complexity of metal AM (additive manufacturing), it can require many trial runs to obtain processing parameters which produce a quality build. Because of this trial and error process, the drive for simulations of AM has grown significantly. A simulation only becomes useful to researchers if it can be shown that it is a true representation of the physical process being simulated. Each process being simulated has a different method of validation to show it is an accurate representation of the process. This paper explores the various methodologies for validation of laser-based metal AM simulations, focusing mainly on …

Industrial Robot Trajectory Accuracy Evaluation Maps For Hybrid Manufacturing Process Based On Joint Angle Error Analysis, Zhiyuan Wang, Renwei Liu, Todd E. Sparks, Xueyang Chen, Frank W. Liou

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Industrial robots have been widely used in various fields. The joint angle error is the main factor that affects the accuracy performance of the robot. It is important to notice that these kinematic parameters error cannot be eliminated from the robot system completely. Even after calibration, these errors still exist and will be fluctuated during the robot system running. This paper proposed a new method of finding the best position and orientation to perform a specific working path based on the current accuracy capacity of the robot system. By analyzing the robot forward/inverse kinematic and the angle error sensitivity of …

A Two-Dimensional Simulation Of Grain Structure Growth Within Substrate And Fusion Zone During Direct Metal Deposition, Jingwei Zhang, Lei Yan, Wei Li, Frank W. Liou

Mechanical and Aerospace Engineering Faculty Research & Creative Works

In this chapter, a predictive multiscale model based on a cellular automaton (CA)-finite element (FE) method has been developed to simulate thermal history and microstructure evolution during metal solidification for direct metal deposition (DMD) process. The macroscopic FE calculation that is validated by the thermocouple experiment is developed to simulate the transient temperature field and cooling rate of single layer and multiple layers. In order to integrate the different scales, a CA-FE coupled model is developed to combine with thermal history and simulate grain growth. In the mesoscopic CA model, heterogeneous nucleation sites, grain growth orientation and rate, epitaxial growth, …

Efficient Inverse Design Of Transonic Airfoils Using Variable-Resolution Models And Manifold Mapping, Xiaosong Du, Leifur Leifsson, Slawomir Koziel

Mechanical and Aerospace Engineering Faculty Research & Creative Works

This paper presents an efficient approach for simulation-based inverse design of airfoil shapes using variable-fidelity computational fluid dynamics models and manifold mapping (MM). Inverse design involves determining an airfoil shape fulfilling a given target performance characteristic. In particular, the pressure coefficient distribution is typically used in aerodynamic inverse design. Such a task can be challenging when using computationally expensive simulations. In the context of local optimization, the MM technique searches for a new design in the vicinity of the current design by constructing a fast multi-fidelity model, which is setup by the available evaluations of each of the high- and …

Monobore Completion Design: Classification, Applications, Benefits And Limitations, Anwar Khaled Al-Fadhli

Masters Theses

"A monobore completion is a simple completion design that uses the same internal diameter from the bottom of the well to surface. This may be accomplished by cementing a string of casing in a well, or by having tubing stabbed into a polished bore receptacle on a casing liner the same size as the tubing. Monobore completions have been applied extensively in oil and gas fields around the world, both onshore and offshore, from very low reservoir flow to extremely high production rates, since the late 1980s. They have proven beneficial due to their simplicity and cost savings. This study …

Data Analysis Of Low-Salinity Waterflooding To Enhance The Oil Recovery In Sandstone Reservoirs, Nadia Ariani

Masters Theses

"The lack of a single reasonable general mechanism to describe how low-salinity waterflooding can improve oil recovery in both laboratory and field pilot projects has increased the interests of many researchers and stakeholders. There has not been observed the relationship of formation brine salinity and injected brine salinity to see how much salinity is reduced to produce the maximum enhanced oil recovery by LSWF. There is no guidance in what EOR stage the LSWF is best implemented. This work collects data from various published literature to develop a comprehensive data set regarding low-salinity waterflooding in sandstone reservoirs. The LSWF mechanisms …

Facile Synthesis Of Nanostructured Metal Borides And Composites For Applications In Sustainable Energy, Maalavan Arivu

Masters Theses

"Electrocatalytic water splitting is a promising solution for sustainable energy generation since one of the half reactions lead to the formation of H₂ which is a clean fuel. The other half of the reaction leading to O₂ evolution is an energy intensive process necessitating the need for an electrocatalyst to break the activation barrier for the commencement of the reaction. In this work we will focus on expanding the family of non-oxidic OER electro-catalysts, especially borides, whereby, apart from facilitating delocalization of electron cloud on the catalytically active transition metal site, low anion electronegativity and increased covalency in …

Thermal Analysis And Control Of Small Satellites In Low Earth Orbit, Katelyn Elizabeth Boushon

Masters Theses

"Small satellites are becoming more popular in the space sector, primarily due to their lower cost and shorter development time. Much of the information available about satellite thermal analysis and control refers to larger spacecraft. Sorting through this information to find the practices specifically applicable for small satellites can be a daunting task, particularly for inexperienced engineers. This thesis study is intended to inform the reader about basic thermal control and analysis methods that relate specifically to small satellites in low Earth orbit. A case study involving a satellite designed by the Missouri University of Science and Technology Satellite Research …

Development And Monte Carlo Validation Of A Finite Element Reactor Analysis Framework, Wayne J. Brewster

Masters Theses

"This study presents the development and Monte Carlo validation of a continuous Galerkin finite element reactor analysis framework. In its current state, the framework acts as an interface between the mesh preparation software GMSH and the sparse linear solvers in MATLAB, for the discretization and approximation of 1-D, 2-D, and 3-D linear partial differential equations. Validity of the framework is assessed from the following two benchmarking activities: the 2-D IAEA PWR benchmark; and the 2-D Missouri Science and Technology Reactor benchmark proposed within this study. The 2-D IAEA PWR multi-group diffusion benchmark is conducted with the following discretization schemes: linear, …

Bioaccessibility Of Lead From Contaminated Soil Using Phosphate Treatment -- Physiologically Based Extraction Test And In Vitro Gastrointestinal Method Test, Austin Charles Doss

Masters Theses

"Phosphate treatments are used to immobilize lead in soil by forming pyromorphite. Soil from Bonne Terre, Mo was collected to study whether such treatment decreases the bioaccessibility of lead. The soil was treated using 0.5 soil wt% of phosphate. Treatments were: none, phosphoric acid, triple super phosphate, and organic bone meal. Each sample was studied after one, four, sixteen, and twenty weeks; during this time span, water was added approximating the average rainfall rate. Percolated water was collected to test the leached phosphate concentrations. Phosphate was below the detection limit in that leachate. Remediated soil samples were used in Physiologically …

An Integrated Method For Understanding The Fluid Flow Behavior And Forecasting Well Deliverability In Gas Condensate Reservoirs With Water Aquifer Drive, Abdulaziz Mustafa Em. Ellafi

Masters Theses

"Gas condensate reservoirs constitute a significant portion of global hydrocarbon reserves. In these reservoirs, as bottomhole pressure falls below the dew point, liquid develops in the pore space. This results in the formation of a liquid bank near the wellbore region that decreases gas mobility, which then reduces gas inflow. Some gas condensate reservoirs have bottom aquifer drive, which also negatively impacts gas production. This research used a field case study to demonstrate an integrated workflow for forecasting well deliverability in a gas condensate field in Libya. The workflow began with the interpretation of open-hole log data to identify the …

Computational Intelligence Methods For Predicting Fetal Outcomes From Heart Rate Patterns, Vinayaka Nagendra Harikishan Gude Divya Sampath

Masters Theses

"In this thesis, methods for evaluating the fetal state are compared to make predictions based on Cardiotocography (CTG) data. The first part of this research is the development of an algorithm to extract features from the CTG data. A feature extraction algorithm is presented that is capable of extracting most of the features in the SISPORTO software package as well as late and variable decelerations. The resulting features are used for classification based on both U.S. National Institutes of Health (NIH) categories and umbilical cord pH data. The first experiment uses the features to classify the results into three different …

Effect Of Variation Of Parameters On Biogas Production Using Aspen Plus & Dynamic Simulation Using Mimic, Shruti Shrikant Karambelkar

Masters Theses

"Design and management for Biogas production have gained significance in growing dependency on Renewable energy resources. This would need a detailed information on steady state and dynamic behavior of systems. In order to make this process environmentally ecofriendly, its needs a lot of improvisation on process simulation. Anaerobic digestion helps treat this inefficient water to be converted into water fit for effluent purposes.

Byproducts contain consists of organic, inorganic and wastes which lead to a high COD content and thus, cannot be discarded into the outlets. The anaerobic digestion process. A study of these effects with simulation need to be …

Multi-Objective Optimal Battery Placement In Distribution Networks, Kiana Khalilnejad

Masters Theses

"Due to high penetration of renewable energy resources in today's electricity generation, considerable voltage fluctuations are witnessed in power systems. As an attempt to solve this issue, in this study, multi-objective optimal placement and sizing of distribution-level battery storage system is performed using semidefinite programing. Placement of one or multiple battery system is studied under various objectives including the cost, voltage regulation, reactive power dispatch, renewable resource curtailment, and minimum network power losses. Power flow equations are solved in the form of semidefinite constraints and the rank constraint is ignored. Additionally, combination of these objectives to form a multi-objective problem …

Recycling Effect In Expanded Granular Sludge Bed Reactor And Implementation Of Six Sigma In A Methane Generation Process, Manohar Manchenahalli Shivashankaraiah

Masters Theses

"Brewery industries are the largest consumers of water among several production industries. Despite consuming these huge amounts of water and electricity, they generate by-products that are harmful to the environment. These by-products contain organic, inorganic, and solid wastes with high chemical oxygen demand (COD) strength. The anaerobic digestion (AD) process plays an important role in treating this wastewater. This study investigates the design and development of an expanded granular sludge bed reactor (EGSB) effluent recirculation, which can achieve high COD removal efficiency of the wastewater and enhance the efficiency of generating biogas with high yields and increases in the concentration …

Nonlinear Finite Element Analysis Of Concrete Columns Subjected To Complex Loading, Adam Christopher Morgan

Masters Theses

"This study details the development and implementation of a finite element model within a commercial finite element code, Abaqus CAE, for the analysis of reinforced concrete (RC) bridge columns containing interlocking spirals subjected to combined loading conditions including axial, shear, bending, and torsional loads, including the post-peak response. The model is a first of its kind attempt at simulating the response of RC columns with continuous spiral transverse reinforcement and subjected to combined loading conditions including torsion. The model is utilized to determine the quasi-static load-deformation response under various proportions of the input loads and displacements. The resulting quasi-static load-deformations, …

Characterization Of Ionic Liquid Monopropellants For A Multi-Mode Propulsion System, Alex J. Mundahl

Masters Theses

"Multi-mode micropropulsion is a potential game-changing technology enabling rapidly composable small satellites with unprecedented mission flexibility. Maximum mission flexibility requires one shared propellant between the chemical and electric systems. A deep eutectic 1:2 molar ratio mixture of choline-nitrate and glycerol ([Cho][NO₃] - glycerol) is investigated as a fuel component in a binary mixture propellant for such a multi-mode micropropulsion. Specifically, binary mixtures of the novel ionic liquid fuel with hydroxyl-ammonium nitrate (HAN) and ammonium nitrate (AN) are considered and compared against the previously investigated propellant [Emim][EtSO₄]-HAN. Chemical rocket performance simulations predict this new propellant to have …

Transmission Line Inspection Using Suspended Robot: Cost Effective Analysis And Operational Routing Identification, Balaji Rathinam Nagarajan

Masters Theses

"High voltage transmission lines form a crucial part of the energy infrastructure of a country. Effective maintenance is required to maintain its reliability and reduce the probability of the occurrence of the outage. Conventionally, the routine inspection of the transmission line was conducted by linemen with the assistance of hot stick and helicopter, which is considered dangerous, time-consuming, and expensive.

In this thesis, we focus on the initial study of seeking the state of the art robotics technology to by largely replace human beings in transmission line inspection. The existing robotics technologies that are interested by utility companies, as well …

Cellulose And Sulfate Degradation In A Biochemical Reactor During Treatment Of Mine Drainage, Sweta Ojha

Masters Theses

"Seventy-two biochemical reactors were set up, and operated using a mixture of chip-bark, horse manure, and gravel as the biochemical treatment substrate. The simulated mine water containing sulfate (1000 mg/l) was pumped into each reactor at a flow rate of 0.5 ml/minute (approximate), giving an empty bed contact time of 8 days. The main idea is that the microorganisms present in horse manure would convert the cellulose in chip-bark into volatile fatty acids. The produced volatile fatty acid would enhance the metabolism of sulfate-reducing bacteria (SRB) initially present in horse manure, which would degrade (and eventually remove) the sulfate from …

Controlling Phase Fractions Of 304l-Ss In Selective Laser Melting Using Cooling Rate, Eberechukwu Anthony Okoro

Masters Theses

"This study examines the thermal profile and the ferrite-austenite phase fractions upon heating and cooling of 304- stainless steel powder via Selective Laser Melting (SLM). Experiments were performed to validate the ABAQUS finite element model, while the phase transformation simulation was performed using MatCalc and ThermoCalc. A correlation between the thermo-mechanical changes in ABAQUS and the microstructural changes from MatCalc was obtained by matching their cooling rates. The result indicates that cooling rate has a significant effect on the phase fractions of FCC and BCC formed in 304L stainless steel via the SLM process. The results also indicate that for …

Cyber-Physical Security Of An Electric Microgrid, Prashanth Palaniswamy

Masters Theses

"Cyber-physical systems (CPSs) are physical systems that are controlled or monitored by computer-based systems. CPSs are a combination of computation, networking, and physical processes. As CPSs are a combination of various diverse components, they are vulnerable to several security threats. Moreover, there are many different security domains (not just high/low, nor necessarily hierarchical). This paper utilizes previously developed multiple security domain nondeducibility (MSDND) to uncover potential integrity vulnerabilities in an electric microgrid. Invariants are manually generated using the insights obtained through MSDND analysis and use linear regression to automate the generation of invariants. The vulnerabilities are then mitigated, to the …

Generalized Adaptive Variable Bit Truncation Model For Approximate Stochastic Computing, Keerthana Pamidimukkala

Masters Theses

"Stochastic computing as a computing paradigm is currently undergoing revival as the advancements in technology make it applicable especially in the wake of the need for higher computing power for emerging applications. Recent research in stochastic computing exploits the benefits of approximate computing, called Approximate Stochastic Computing (ASC), which further reduces the operational overhead in implementing stochastic circuits. A mathematical model is proposed to analyze the efficiency and error involved in ASC. Using this mathematical model, a new generalized adaptive method improving on ASC is proposed in the current thesis. The proposed method has been discussed with two possible implementation …

An Approach For Formal Analysis Of The Security Of A Water Treatment Testbed, Sai Sidharth Patlolla

Masters Theses

"This thesis focuses on securing critical infrastructures such as chemical plants, manufacturing units, and power generating plants against attacks that disrupt the information flow from one component to another. Such systems are controlled by an Industrial Control System (ICS) that includes controllers communicating with each other, and with physical sensors and actuators, using a communications network.

Traditional security models partition the security universe into two worlds, secure and insecure, but in the real world the partitions often overlap and information is leaked even through the physical observation which makes it much harder to analyze a Cyber physical system (CPS). To …

Fuel Burnup Simulation And Analysis Of The Missouri S&T Reactor, Joshua Hinkle Rhodes

Masters Theses

"The purpose of this work is to simulate the fuel burnup of the Missouri S&T Reactor. This work was accomplished using the Monte Carlo software MCNP. The primary core configurations of MSTR were modeled and the power history was used to determine the input parameters for the burnup simulation. These simulations were run to determine the burnup for each fuel element used in the core of MSTR.

With these simulations, the new predicted isotopic compositions were added into the model. New core configurations were determined, and the burnup corrected model was used to predict the excess reactivity and control rod …

Investigation Of The Information Provided By Light Touch For Balance Improvement In Humans, Anirudh Saini

Masters Theses

"This study investigates the information provided by Light Touch (LT) in improving human postural stability without mechanical assistance. Light Touch, an interaction force with a magnitude about 1 N, is known to improve postural stability in humans during quiet standing. However, the nature of the information from LT that helped improve balance is yet unknown. In this work, we hypothesized that LT provides information about one's body kinematics. We used a haptic robot to provide modulated, measurable light interaction force on the high back haptic location of humans to provide body kinematics-dependent information through LT. Standing balance experiments were performed …