Mechanical Engineering Commons^™

High-Temperature Phonon-Assisted Upconversion Photoluminescence Of Monolayer Wse2, Fengkai Meng, Xiaodong Yang, Jie Gao

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Phonon-assisted up conversion photoluminescence (UPL) is an anti-Stokes process emitting photons of energy higher than the excitation photons, with up conversion energy gain provided by optical phonons. Atomically thin transition metal dichalcogenides provide a promising platform for exploring the phonon-assisted UPL process due to their strong phonon-exciton interactions. Here, high-temperature phonon-assisted UPL process in monolayer WSe2 is investigated, aiming to understand the role of phonon population and the number of phonons involved in the UPL process at elevated temperatures. It is demonstrated that the integrated intensity of UPL emission significantly increases by two orders of magnitude as the temperature rises …

On The Development Of Part-Scale Fem Modeling For Laser Powder Bed Fusion Of Aisi 316l Stainless Steel With Experimental Verification, Muhammad Arif Mahmood, Asif Ur Rehman, M. Mustafa Azeem, Abedalkader Alkhouzaam, Marwan Khraisheh

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

In laser powder bed fusion (LPBF), the effects of operating conditions on thermal gradients and residual stresses are the utmost challenges that require significant attention. The magnitudes of residual stress in the printed layers, as well as the distribution along the printed components, have not been well explained for LPBF parts. In this study, a 3D finite element thermo-mechanical model has been established to investigate the effect of operating conditions on thermal distribution, melt pool evolution, residual stress distribution, and part distortion. The printed AISI 316L stainless steel cubes have been characterized experimentally. The results showed a proportional correlation among …

Kinetic Particle Simulations Of Plasma Charging At Lunar Craters Under Severe Conditions, David Lund, Xiaoming He, Daoru Frank Han

Mathematics and Statistics Faculty Research & Creative Works

This paper presents fully kinetic particle simulations of plasma charging at lunar craters with the presence of lunar lander modules using the recently developed Parallel Immersed-Finite-Element Particle-in-Cell (PIFE-PIC) code. The computation model explicitly includes the lunar regolith layer on top of the lunar bedrock, taking into account the regolith layer thickness and permittivity as well as the lunar lander module in the simulation domain, resolving a nontrivial surface terrain or lunar lander configuration. Simulations were carried out to study the lunar surface and lunar lander module charging near craters at the lunar terminator region under mean and severe plasma environments. …

Decomposition Of The Wall-Heat Flux Of Compressible Boundary Layers, Dongdong Xu, Pierre Ricco, Lian Duan

Mechanical and Aerospace Engineering Faculty Research & Creative Works

We use the method developed by Elnahhas and Johnson ["On the enhancement of boundary layer skin friction by turbulence: An angular momentum approach," J. Fluid Mech. 940, A36 (2022)] and Xu et al. ["Decomposition of the skin-friction coefficient of compressible boundary layers," Phys. Fluids 35, 035107 (2023)] for the decomposition of the skin-friction coefficient to integrate the mean temperature equation for high-Reynolds-number compressible boundary layers and arrive at an identity for the decomposition of the wall-heat flux. The physical interpretation of the identity and the limitations of this approach are discussed. We perform an integration on the mean temperature equation …

A Hybrid Admm For Six-Degree-Of-Freedom Entry Trajectory Optimization Based On Dual Quaternions, Chaoying Pei, Changhuang Wan, Ran Dai, Jeremy R. Rea

Mechanical and Aerospace Engineering Faculty Research & Creative Works

This article investigates the six-degree-of-freedom (6-DoF) entry trajectory optimization problem in a Human-Mars entry, powered descent, and landing mission. During the entry phase, aerodynamic forces are employed to decelerate the vehicle. Instead of being treated as a point mass, both translational and rotational motions of the entry vehicle are considered. Specifically, the 6-DoF rigid body motion of the entry vehicle is modeled using the unit dual quaternion representations to avoid highly nonlinear terms in the flight dynamics expression originally based on the flight-path coordinates. Then, the entry trajectory optimization problem is to minimize the terminal speed subject to dynamical, operational, …

Characterizing Energy Dissipation Of Shallow-Water Wave Breaking In A Storm Surge, Hunter Boswell, Guirong Grace Yan, Wouter Mostert

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

While understanding breaking waves is crucial for the development of parametrizations used in ocean wave modeling for both deep and shallow water, the complete process of wave breaking is not well understood. Here we present direct numerical simulations of two-dimensional solitary waves that shoal and break on a uniform beach in shallow water, with the presence of storm surge represented by an inshore region. The storm surge depth, beach slope, and wave amplitude are varied to study the dependence of energy dissipation in the breaker on wave and bathymetric parameters. We classify wave breaker types and find a separation between …

Multifunctional Additive Manufacturing And Multiphysics Numerical Investigations Of Carbon Fiber Structural Battery Composite Using A Drop-On-Demand Method With In-Situ Consolidation, Xiangyang Dong, Yuekun Chen

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Lightweight Carbon Fiber Structural Battery Composite Has Great Potential in Increasing Structural Energy Storage Efficiency for Multifunctional Applications. However, It is Still Challenging to Design Carbon Fiber Multifunctional Composite Due to Lack of Proper Manufacturing Methods. in This Study, an Integrated Multifunctional Design and Fabrication Approach is Developed by Combining a Drop-On-Demand Additive Manufacturing Method with a Multiphysics Numerical Model to Guide the Development of the New Multifunctional Composite. through Deposition with In-Situ Consolidation, the Function and Thickness of Each Carbon Fiber Layer as Well as its Fiber Volume Fraction Are Accurately Controlled. Decreasing Layer Thickness Improves Flexural Properties. the …

Servo Mounting Device And Collective Control System Design For The Forward Flight Aero Test Stand, Aaron Jones

NASA-Missouri Space Grant Consortium

The majority of the ten-week internship was spent designing a servo mounting device, and a collective control system for the Forward Flight Aero Test (FFAT) stand. The servo mounting device uses four threaded standoffs along with a top plate, held together with screws, that raises the servos above the protruding threaded rods and screws. The collective control system is a rectangular block that attaches the swashplate to the servo arms connected to the servo motor. This control rod is used to translate the rotation from the servo arm into collective control for the blade angle. The control rod has two …

An Introductory Investigation Of Dust Devils On Mars: Computational Fluid Dynamics Modeling, Alexios Nicolas Philippou, Kakkattukuzhy M. Issac

NASA-Missouri Space Grant Consortium

This report investigates the flow characteristics of tornado like vortices which can be used to describe an array of axisymmetric rotating vertical columns of fluid such as dust devils, steam devils and tornadoes. These vortices have been recreated within vortex chambers in research facilities, but in focus of this report the investigation is conducted through numerical simulations using the Computational Fluid Dynamics (CFD) software package provided by ANSYS. By varying the main governing nondimensional parameter of swirl ratio through the computational domain’s boundary conditions, different flow characteristics appear which confirm theories presented in previous papers. This enables the research conducted …

Modeling And Simulation Of An Electrostatic Lunar Particle Sieve, Aaron Berkhoff

NASA-Missouri Space Grant Consortium

The following research was conducted to develop a kinetic particle model, which simulates an electromagnetic sieve used for in-situ material utilization on the lunar surface. A code package was developed to simulate an electromagnetic sieve that uses electrodes to transport fine particles within a cylindrical device. Specifically, this research generates an initial working model for the sieve and tests different electrode configurations. The simulation models different electric fields generated by electrodes, kinetic particle dynamics, and lunar particle distribution. During the case study, which investigates different electrode configurations, it was determined that electrodes oriented such that electrodes located above and below …

Nationwide Eclipse Ballooning Project: April 2023 Status Report, Jill Schmidt

NASA-Missouri Space Grant Consortium

This report details the progress of the Missouri S&T Nationwide Eclipse Ballooning Project as of April 2023 and the future work the team will complete throughout the remainder of 2023 and 2024. This project began in January 2023, and students have been completing preliminary training activities, so they are prepared to begin assembling and testing the eclipse payloads during summer 2023. Throughout the summer, all team members will be actively engaged in this research project and participating in outreach events related to high altitude ballooning.

High Pressure Injection Process For Ceramic Composites, Samuel Weiler

NASA-Missouri Space Grant Consortium

Ceramic materials are valued for good heat resistance and corrosion resistance. Due to these benefits, they are widely used in the aviation, automotive, medical, construction, and other industries. Ceramic materials are also both hard and brittle, qualities that are not ideal in many applications. To reduce brittleness, and other undesirable characteristics of ceramics, engineers have turned to composites to increase the mechanical properties of these materials. By adding composite particles or fibers, these characteristics can be improved. Constructing ceramic composites is not without its challenges, however. Current processes are prone to high porosity, high shrinkage, and poor accuracy of parts. …

Performance Evaluation Of Additively Manufactured Carbon/Peek Composites, Matik S. Heskin

NASA-Missouri Space Grant Consortium

Carbon/PEEK composites have a broad range of applications due to their combinations of superior creep properties and excellent strength to weight ratios. Like all fiber-based composites they are limited geometrically by their required manufacturing processes. Additively manufactured (AM) materials overcome this issue and can be formed into incredibly complex shapes. By combining these two fields, a material limited in application by geometry can have its shortcomings supported with AM processes.

AM carbon/PEEK composites have already been created but this relatively new material still needs property characterization. Therefore, the objective of this work will be to evaluate the structural performance of …

From Land Grant To Space Grant, Mohammad Dehghani

NASA-Missouri Space Grant Consortium

No abstract provided.

Comparison Of Injection Molded Abs Using Conventional Steel And Novel Composite-Based Additively Manufactured Mold Plates, John Mitchell

NASA-Missouri Space Grant Consortium

Polymer injection molding processes have been used for over 100 years to create high-volume parts quickly and efficiently. Injection molding uses mold plates that are traditionally made of very hard tool steels, such as P20 steel, which is extremely heavy and has very long lead times to build new molds. In this study, composite-based additive manufacturing (CBAM) was used to create mold plates using long-fiber carbon fiber and polyether ether ketone (PEEK). These mold plates were installed in an injection molding machine, and rectangular flat plates were produced using Lustran 348 acrylonitrile butadiene styrene (ABS). Tensile testing was performed on …

Multi-Disciplinary Analysis Surrogate Based On Twin-Generator Generative Adversarial Networks For Electric Drone, Samuel Sisk

NASA-Missouri Space Grant Consortium

Multi-Disciplinary Analysis and Optimization (MDAO) plays an important role in the future of aviation, especially relating to Urban Air Mobility (UAM). MDAO for UAM effectively quantifies and maximizes system performance and safety while minimizing cost or consumption. Electric drone takeoff trajectory design aims to minimize energy consumption while fulfilling acceleration and other constraints to keep passengers comfortable. Conventional simulation-based MDAO is computationally expensive due to repeatedly evaluating physics-based models while naïvely constructing machine learning predictive models, also known as surrogate models, do not scale well with large-scale problems due to the “curse of dimensionality”. A twin-generator generative adversarial networks (Twin-GAN) …

Progress In Optimization Of Electrostatic Sieve Concept For Transport Of Lunar Regolith Using A Genetic Algorithm, Easton Ingram

NASA-Missouri Space Grant Consortium

A method for optimizing electrostatic dust transport systems using a genetic algorithm is in development. Applications to electrostatic sieving are discussed for use on the lunar surface. This simulation will allow for rapid development, testing, and optimization of electrostatic particle transport designs with large search spaces. Current progress and ongoing work for the simulation is reviewed.

Lunar In-Situ Aluminum Production Through Molten Salt Electrolysis (Lisap-Mse), Jacob Ortega, Jeffrey D. Smith, Fateme Rezaei, David Bayless, William P. Schonberg, Daniel S. Stutts, Daoru Frank Han

NASA-Missouri Space Grant Consortium

The goal of Artemis is to establish a sustained presence on the Moon. To achieve so, numerous resources are necessary. The Moon contains several essential elements needed to sustain human presence. Most of those elements are trapped in the form of minerals. To refine those minerals into useful materials, reduction methods are needed. Most reduction methods on Earth require large amounts of mass and power which is unrealistic for early stages of building a lunar base. To solve this problem, we are developing a concept of Lunar In-Situ Aluminum Production through Molten Salt Electrolysis (LISAP-MSE).

The LISAP-MSE project, if successful, …

Supersonic Wind Tunnel Improvement For Advanced Laser-Based Non-Intrusive Diagnostics, Joshua Gary

NASA-Missouri Space Grant Consortium

This work presents an approach to the design, and theoretical application, of a new test section for the Missouri S&T Supersonic Wind Tunnel to be used with advanced laserbased non-intrusive diagnostics. Supersonic wind tunnel test sections present multiple challenges. They need to ensure proper flow by avoiding jet-flow interactions and ensuring started conditions; they need to withstand large pressure loads in the case of tunnel unstart; they need to provide easy optical access for advanced diagnostics; they need to be modular and adaptable for different experiments. This work presents detailed analytical and numerical analyses of the mechanical loads. Based on …

Experimental And Numerical Studies Of Slurry-Based Coextrusion Deposition Of Continuous Carbon Fiber Micro-Batteries To Additively Manufacture 3d Structural Battery Composites, Aditya R. Thakur, Xiangyang Dong

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Carbon Fiber Structural Battery Composites Have Recently Attracted Growing Interests Due to their Potentials of Simultaneously Carrying Mechanical Loads and Storing Electrical Energy for Lightweight Application. in This Study, We Present a Slurry-Based Coextrusion Deposition Method to Additively Manufacture 3D Structural Battery Composites from Carbon Fiber Micro-Batteries. Cathode Slurry is Coextruded Together with Solid Polymer Electrolyte-Coated Carbon Fibers in a Single Deposition. a Network of Carbon Fiber Micro-Batteries is Achieved within the Fabricated Structural Battery Composites. Electrochemical Tests Show a Stable Charge-Discharge Performance Up to 100 Cycles. the Rheological Behavior of the Cathode Slurry is Found to Govern the Coextrusion …

A High-Strength Precipitation Hardened Cobalt-Free High-Entropy Alloy, Matthew Luebbe, Jiaqi Duan, Fan Zhang, Jonathan Poplawsky, Hans Pommeranke, Maalavan Arivu, Andrew Hoffman, Mario Buchely, Haiming Wen

Materials Science and Engineering Faculty Research & Creative Works

Recent studies on precipitation-hardened high-entropy alloys (HEAs) demonstrate their high strength and thermal stability, making them promising materials for high-temperature structural applications such as nuclear reactors. However, many existing HEAs contain cobalt (Co), which is unsuitable for nuclear applications because of the long-term activation issue of Co. Co is also expensive and considered a critical material for other applications. Therefore, it is desired to exclude Co from the composition. a Co-free (Fe0.3Ni0.3Mn0.3Cr0.1)88Ti4Al8 HEA was developed and studied in this work. in contrast to previous Co-free HEAs, this alloy is close to Equi atomic in its composition and promises a more …

Sharprazor: Automatic Removal Of Hair And Ruler Marks From Dermoscopy Images, Reda Kasmi, Jason Hagerty, Reagan Harris Young, Norsang Lama, Januka Nepal, Jessica Miinch, William V. Stoecker, R. Joe Stanley

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Background: The removal of hair and ruler marks is critical in handcrafted image analysis of dermoscopic skin lesions. No other dermoscopic artifacts cause more problems in segmentation and structure detection. Purpose: The aim of the work is to detect both white and black hair, artifacts and finally inpaint correctly the image. Method: We introduce a new algorithm: SharpRazor, to detect hair and ruler marks and remove them from the image. Our multiple-filter approach detects hairs of varying widths within varying backgrounds, while avoiding detection of vessels and bubbles. The proposed algorithm utilizes grayscale plane modification, hair enhancement, segmentation using tri-directional …

Advanced Ensemble Modeling Method For Space Object State Prediction Accounting For Uncertainty In Atmospheric Density, Smriti Nandan Paul, Richard J. Licata, Piyush M. Mehta

Mechanical and Aerospace Engineering Faculty Research & Creative Works

For objects in the low Earth orbit region, uncertainty in atmospheric density estimation is an important source of orbit prediction error, which is critical for space traffic management activities such as the satellite conjunction analysis. This paper investigates the evolution of orbit error distribution in the presence of atmospheric density uncertainties, which are modeled using probabilistic machine learning techniques. The recently proposed "HASDM-ML," "CHAMP-ML," and "MSIS-UQ" machine learning models for density estimation (Licata and Mehta, 2022b; Licata et al., 2022b) are used in this work. The investigation is convoluted because of the spatial and temporal correlation of the atmospheric density …

Decomposition Of The Skin-Friction Coefficient Of Compressible Boundary Layers, Dongdong Xu, Pierre Ricco, Lian Duan

Mechanical and Aerospace Engineering Faculty Research & Creative Works

We derive an integral formula for the skin-friction coefficient of compressible boundary layers by extending the formula of Elnahhas and Johnson ["On the enhancement of boundary layer skin friction by turbulence: An angular momentum approach, "J. Fluid Mech. 940, A36 (2022)] for incompressible boundary layers. The skin-friction coefficient is decomposed into the sum of the contributions of the laminar coefficient, the change of the dynamic viscosity with the temperature, the Favre-Reynolds stresses, and the mean flow. This decomposition is applied to numerical data for laminar and turbulent boundary layers, and the role of each term on the wall-shear stress is …

Simulation Of Natural Tornado Genesis And Evolution From An Initial Instability Profile, Kakkattukuzhy M. Issac

Mechanical and Aerospace Engineering Faculty Research & Creative Works

A likely mechanism for the little-understood tornado genesis is proposed and its numerical implementation is presented. The Burgers-Rott vortex with its axis in the vertical direction is introduced as an instability mechanism, and the flow field then evolves under the influence of the atmospheric pressure, temperature and density variations with altitude. Buoyancy effects are implemented using the Boussinesq model. Results are presented and discussed for a set of conditions including mesh type and size, different turbulence models, and a few different boundary conditions. Post-processed results of the transient simulations including animations contain a wealth of information to help analyze tornado …

Selection Of Solidification Pathway In Rapid Solidification Processes, Nima Najafizadeh, Men G. Chu, Yijia Gu

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Rapid Solidification Processing of Alloys Enables the Formation of Exotic Nonequilibrium Microstructures. However, the Interrelationship between the Processing Parameters and the Resulting Microstructure is Yet to Be Fully Understood. in Melt Spinning (MS) and Additive Manufacturing (AM) of Rapidly Solidified Alloys, Opposite Microstructure Development Sequences Were Observed. a Fine-To-Coarse Microstructural Transition is Typically Observed in Melt-Spun Ribbons, Whereas Melt Pools in AM Exhibit a Coarse-To-Fine Transition. in This Paper, the Microstructural Evolutions during These Two Processes Are Investigated using Phase-Field Modeling. the Variation of All Key Variables of the Solid-Liquid Interface (Temperature, Composition, and Velocity) throughout the Entire Rapid Solidification …

Glass-Based Biodegradable Pressure Sensor Toward Biomechanical Monitoring With A Controllable Lifetime, Devdatt Chattopadhyay, Jonghyun Park, Chang-Soo Kim

Mechanical and Aerospace Engineering Faculty Research & Creative Works

A New Class of Potentially Implantable Solid-State Sensors is Demonstrated Utilizing Biodegradable Glass as the Main Structural Material. the Device Behavior is Manipulated Via Chemical Decomposition, and Then Physically Disintegrated in a Controlled Manner. It is based on the Capacitive Sensing Mechanism, Comprising an Elastic Insulator between Two Borate-Rich Glass Substrates. This Mesoscale Pressure Sensor is Characterized by a Range of Pressure of Up to 14 MPa in a Phosphate Buffer Solution Environment. the Sensor Exhibits Good Sensitivity and Reversibility Responding to Compressive Pressures and Remains Fully Functional Before a Desired, Sudden Failure Caused by Dissolution. the Operational Lifetime Can …

Synthesizing Ti–Ni Alloy Composite Coating On Ti–6al–4v Surface From Laser Surface Modification, Yitao Chen, Joseph William Newkirk, Frank W. Liou

Materials Science and Engineering Faculty Research & Creative Works

In This Work, a Ni-Alloy Deloro-22 Was Laser-Deposited on a Ti–6Al–4V Bar Substrate with Multiple Sets of Laser Processing Parameters. the Purpose Was to Apply Laser Surface Modification to Synthesize Different Combinations of Ductile TiNi and Hard Ti₂Ni Intermetallic Phases on the Surface of Ti–6Al–4V in Order to Obtain Adjustable Surface Properties. Scanning Electron Microscopy, Energy Dispersion Spectroscopy, and X-Ray Diffraction Were Applied to Reveal the Deposited Surface Microstructure and Phase. the Effect of Processing Parameters on the Resultant Compositions of TiNi and Ti₂Ni Was Discussed. the Hardness of the Deposition Was Evaluated, and Comparisons with …

3d-Printed Hydrogels Dressings With Bioactive Borate Glass For Continuous Hydration And Treatment Of Second-Degree Burns, Fateme Fayyazbakhsh, Michael J. Khayat, Candy Sadler, Delbert Day, Yue-Wern Huang, Ming-Chuan Leu

Biological Sciences Faculty Research & Creative Works

Recent advances in additive manufacturing have led to the development of innovative solutions for tissue regeneration. Hydrogel materials have gained significant attention for burn wound treatment in clinical practice among various advanced dressings due to their soothing and moisturizing activity. However, prolonged healing, pain, and traumatic removal due to the lack of long-term wound hydration are some of the challenges in the treatment of second-degree burn wounds. In this study, 3D-printed dressings were fabricated using gelatin, alginate, and bioactive borate glass (BBG) using an extrusion-based bioprinter. After ionic crosslinking, the 3D-printed dressings were characterized for mechanical properties, degradation rate, hydration …

Performance Evaluation Of Composite Sandwich Structures With Additively Manufactured Aluminum Honeycomb Cores With Increased Bonding Surface Area, M. Rangapuram, S. K. Dasari, Joseph William Newkirk, K. Chandrashekhara, H. Misak, P. R. Toivonen, D. Klenosky, T. Unruh, J. Sam

Materials Science and Engineering Faculty Research & Creative Works

Modern aerostructures, including wings and fuselages, increasingly feature sandwich structures due to their high-energy absorption, low weight, and high flexural stiffness. The face sheet of these sandwich structures are typically thin composite laminates with interior honeycombs made of Nomex or aluminum. Standard cores are structurally efficient, but their design cannot be varied throughout the structure. With additive manufacturing (AM) technology, these core geometries can be altered to meet the design requirements that are not met in standard honeycomb cores. This study used a modified aluminum honeycomb core, with increased surface area on the top and bottom, as the core material …