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Articles 241 - 270 of 3263
Full-Text Articles in Aerospace Engineering
Towards Universal Non-Dimensional Characterization Of The Oscillatory Dynamics Of Wind Turbine Rotors Of Multiple Sizes, North Yates, Fernando L. Ponta, Alayna Farrell
Towards Universal Non-Dimensional Characterization Of The Oscillatory Dynamics Of Wind Turbine Rotors Of Multiple Sizes, North Yates, Fernando L. Ponta, Alayna Farrell
Michigan Tech Publications
One concern in the field of Horizontal Axis Wind Turbines (HAWTs) is what control strategies are needed to handle gust pulses in the wind to prevent extreme oscillations of the blades to reduce fatigue stress, prevent blade rupture, and extend the turbine’s operational life. In order to design innovative control strategies to modify the blade’s oscillatory response, it is crucial to establish the fundamental vibrational behavior of the blades when excited by gust pulses of different frequencies and amplitudes present in the fluctuating wind inflow. In a series of previous works, the authors presented a novel Reduced-Order Characterization (ROC) technique …
Wind Tunnel Testing Of A Novel Quadrotor Design, Oliver Marius Tobisch
Wind Tunnel Testing Of A Novel Quadrotor Design, Oliver Marius Tobisch
Mechanical & Aerospace Engineering Theses & Dissertations
This study presents the test development and aerodynamic evaluation of the Quadfoil UAV, a novel quadrotor configuration featuring a central lifting body in the form of an airfoil to enhance forward-flight efficiency. Flight tests conducted by Virginia Tech demonstrated a 25% increase in endurance and a 32% improvement in range compared to conventional quadcopters, validating the aerodynamic benefits of this design. To further investigate its performance, a dynamically adjustable angle of attack model support system was developed for wind tunnel testing, enabling precise replication of in-flight conditions. The support system, controlled via LabVIEW, adjusts angle of attack based on real-time …
Multiphase Iterative Algorithm For Mixed-Integer Optimal Control, Chaoying Pei, Sixiong You, Yu Di, Ran Dai
Multiphase Iterative Algorithm For Mixed-Integer Optimal Control, Chaoying Pei, Sixiong You, Yu Di, Ran Dai
Mechanical and Aerospace Engineering Faculty Research & Creative Works
Mixed-integer optimal control problems (MIOCPs) frequently arise in the domain of optimal control problems (OCPs) when decisions including integer variables are involved. However, existing state-of-the-art approaches for solving MIOCPs are often plagued by drawbacks such as high computational costs, low precision, and compromised optimality. In this study, we propose a novel multiphase scheme coupled with an iterative second-order cone programming (SOCP) algorithm to efficiently and effectively address these challenges in MIOCPs. In the first phase, we relax the discrete decision constraints and account for the terminal state constraints and certain path constraints by introducing them as penalty terms in the …
Experimental Investigation Of Heat Transfer To Tightly Packed Cylinder Arrays, Cameron M. Sexsmith
Experimental Investigation Of Heat Transfer To Tightly Packed Cylinder Arrays, Cameron M. Sexsmith
Doctoral Dissertations and Master's Theses
With the increased emphasis on the development of hybrid electric aircraft and other electric driven vehicles, the thermal demand on batteries is increasing. Unique to the aviation sector is the combined need of high battery thermal loads and a light-weight thermal management system. A proposed configuration is an array of batteries directly cooled with a dielectric coolant. The knowledge of heat transfer characteristics of battery cooling is becoming an ever pressing issue due to the need to optimize volume and mass in a safe manner. Tighter spacings between batteries provide higher pack densities, however, at the cost of increased cooling …
Wind Tunnel Automation For Propeller Testing, David Ricardo Lara
Wind Tunnel Automation For Propeller Testing, David Ricardo Lara
Mechanical & Aerospace Engineering Theses & Dissertations
An automated propeller test capability for the ODU Low-Speed Wind Tunnel Facility is demonstrated; implementing automation improved both ease of testing and quality of results. An experiment was performed with and without automation to compare results. Prior to this effort, propeller RPM and airstream velocity were manually controlled, leading to time consuming experiments. The setpoint for RPM had to be adjusted at each run to compensate for changes in airstream velocity.
LabVIEW, a graphical programming software, was used to develop the controllers and automation algorithm. A Proportional Integral Derivative (PID) control approach was developed to simultaneously control airstream velocity and …
Estimating Snow Coverage Percentage On Solar Panels Using Drone Imagery And Machine Learning For Enhanced Energy Efficiency, Ashraf Saleem, Ali Awad, Amna Mazen, Zoe Mazurkiewicz, Ana Dyreson
Estimating Snow Coverage Percentage On Solar Panels Using Drone Imagery And Machine Learning For Enhanced Energy Efficiency, Ashraf Saleem, Ali Awad, Amna Mazen, Zoe Mazurkiewicz, Ana Dyreson
Michigan Tech Publications
Snow accumulation on solar panels presents a significant challenge to energy generation in snowy regions, reducing the efficiency of solar photovoltaic (PV) systems and impacting economic viability. While prior studies have explored snow detection using fixed-camera setups, these methods suffer from scalability limitations, stationary viewpoints, and the need for reference images. This study introduces an automated deep-learning framework that leverages drone-captured imagery to detect and quantify snow coverage on solar panels, aiming to enhance power forecasting and optimize snow removal strategies in winter conditions. We developed and evaluated two approaches using YOLO-based models: Approach 1, a high-precision method utilizing a …
Enhancing Gas Cyclone Performance With Exit Diffusers, Omar Mohamed Mourad Dwidar, Yasser El-Shaer, Khairy Elsayed, Seyyed Hossein Hosseini, Goodarz Ahmadi
Enhancing Gas Cyclone Performance With Exit Diffusers, Omar Mohamed Mourad Dwidar, Yasser El-Shaer, Khairy Elsayed, Seyyed Hossein Hosseini, Goodarz Ahmadi
Journal of Engineering Research
This study evaluates seven cyclone designs to enhance pressure drop and collection efficiency (CE), using the conventional cyclone as a baseline. While the conventional design is efficient in particle collection, it experiences significant energy losses due to high values of pressure drops. This study introduces exit diffusers with various configurations—A, B, C, D, E, and F—to improve cyclone performance. Computational Fluid Dynamics (CFD) simulations were used to analyse the pressure drop, tangential velocity, and static pressure at different levels of each cyclone. The findings reveal that cyclone D achieves a 41.1% reduction in pressure drop but at the cost …
Lifting-Line Predictions For The Ideal Twist Effectiveness Of Spanwise Continuous And Discrete Control Surfaces, Zachary S. Montgomery, Douglas F. Hunsaker, James J. Joo
Lifting-Line Predictions For The Ideal Twist Effectiveness Of Spanwise Continuous And Discrete Control Surfaces, Zachary S. Montgomery, Douglas F. Hunsaker, James J. Joo
Mechanical and Aerospace Engineering Faculty Publications
Modern materials and manufacturing technologies have allowed the construction of morphing wings that are able to continuously vary certain airfoil parameters such as twist, camber, or control surface deflection as a function of span. This work presents a twist effectiveness parameter as a means of comparing the ideal aerodynamic efficiency of spanwise continuous control surfaces (morphing wings) and spanwise discrete control surfaces (standard wings). A numerical algorithm is used to compute the twist effectiveness of both continuous and discrete control-surface designs over a wide range of planform shapes with evenly spaced actuation for inviscid, incompressible flow. Results included here show …
Evidence Of Pure Ammonia Clouds In Jupiter's Northern Temperate Domain From Juno/Jiram Infrared Spectral Data, F. Biagiotti, D. Grassi, G. Liuzzi, G. Villanueva, G. Piccioni, T. Guillot, Shawn Brueshaber, Et. Al.
Evidence Of Pure Ammonia Clouds In Jupiter's Northern Temperate Domain From Juno/Jiram Infrared Spectral Data, F. Biagiotti, D. Grassi, G. Liuzzi, G. Villanueva, G. Piccioni, T. Guillot, Shawn Brueshaber, Et. Al.
Michigan Tech Publications
In this work, we analyse data from the Jovian Infrared Auroral Mapper (JIRAM) imaging spectrometer on board the NASA mission Juno, to investigate the presence of spectrally identifiable ammonia clouds (SIACs). Focusing on the data from the first perijove passage, we found that a white vortex structure near 40°N provides the best candidate. Implementing atmospheric retrieval thanks to the planetary spectrum generator, we fit the JIRAM spectra (in the 2.5-3.1 μm range) inside and outside the vortex, varying the gaseous ammonia profiles, and the clouds and hazes properties and composition. We found that outside the vortex, the best fit …
Experiment-Based Superposition Thermal Modeling Of Laser Powder Bed Fusion, Cody S. Lough, Tao Liu, Robert G. Landers, Douglas A. Bristow, James A. Drallmeier, Ben Brown, Edward C. Kinzel
Experiment-Based Superposition Thermal Modeling Of Laser Powder Bed Fusion, Cody S. Lough, Tao Liu, Robert G. Landers, Douglas A. Bristow, James A. Drallmeier, Ben Brown, Edward C. Kinzel
Mechanical and Aerospace Engineering Faculty Research & Creative Works
Parts experience significant local thermal variations during the Laser Powder Bed Fusion (LPBF) metal Additive Manufacturing (AM) process, providing a potential source of defects. Near real-time thermal predictions can enable better process planning and facilitate corrections on subsequent layers to enable the engineering of laser parameter and scan path combinations that avoid defect inducing scenarios. This paper considers an experiment-based Discrete Green's Function (DGF) thermal model for temperature field prediction in LPBF. An analytical framework is developed and used to calculate an experimental DGF (i.e., powder bed's single pulse temperature response) from spatiotemporal Short-Wave Infrared (SWIR) camera data. The extracted …
Biomedically Vibrant And Cost-Effective Biocomposite Bone Plate – Development And Testing, Asif Mahmud Rayhan, Md Enamul Hoque, Adib Bin Rashid
Biomedically Vibrant And Cost-Effective Biocomposite Bone Plate – Development And Testing, Asif Mahmud Rayhan, Md Enamul Hoque, Adib Bin Rashid
Michigan Tech Publications
Bone fracture treatment requires a supportive structure called, bone plate for a specific period required to heal the fractured bone. Titanium, stainless steel, tantalum etc. are widely used as bone plates. However, these metallic bone plates lead to some major problems namely, stress shielding, bone atrophy, high cost etc. because of their very high strength compared to bones. In addition, the metallic bone plates need secondary surgery to remove it from the body. This research aims to develop a sustainable composite bone plate that is biocompatible, bio-functional, and biodegradable in the human body. Firstly, different composite samples were fabricated using …
Solid State Transformer Controls For Mitigation Of E3a High-Altitude Electromagnetic Pulse Insults, Connor A. Lehman, Rush D. Robinett, Wayne Weaver, David G. Wilson
Solid State Transformer Controls For Mitigation Of E3a High-Altitude Electromagnetic Pulse Insults, Connor A. Lehman, Rush D. Robinett, Wayne Weaver, David G. Wilson
Michigan Tech Publications
This paper explores the use of a solid state transformer (SST) to mitigate the 𝐸3𝐴 component of a high-altitude electromagnetic pulse (HEMP) insult using external energy storage optimal control techniques. In lieu of conventional passive blocking devices or feedback-controlled energy storage devices, a novel implementation of Hamiltonian error tracking is utilized to develop a feedback control law for the variable converter ratio in an SST. The findings of the simulations performed in this paper suggest that additional energy storage is not necessary to protect an individual load from a HEMP insult. The simulations performed examine the response of a single-phase …
Quality Evaluation For Colored Point Clouds Produced By Autonomous Vehicle Sensor Fusion Systems, Colin Schaefer, Zeid Kootbally, Vinh Nguyen
Quality Evaluation For Colored Point Clouds Produced By Autonomous Vehicle Sensor Fusion Systems, Colin Schaefer, Zeid Kootbally, Vinh Nguyen
Michigan Tech Publications
Perception systems for autonomous vehicles (AVs) require various types of sensors, including light detection and ranging (LiDAR) and cameras, to ensure their robustness in driving scenarios and weather conditions. The data from these sensors are fused together to generate maps of the surrounding environment and provide information for the detection and tracking of objects. Hence, evaluation methods are necessary to compare existing and future sensor systems through quantifiable measurements given the wide range of sensor models and design choices. This paper presents an evaluation method to compare colored point clouds, a common fused data type, among two LiDAR-camera fusion systems …
Stabilizing A Bio-Inspired Rotating Empennage Fighter Aircraft In Multiple Trim Scenarios, Benjamin C. Moulton, Matthew W. Harris, Douglas F. Hunsaker
Stabilizing A Bio-Inspired Rotating Empennage Fighter Aircraft In Multiple Trim Scenarios, Benjamin C. Moulton, Matthew W. Harris, Douglas F. Hunsaker
Mechanical and Aerospace Engineering Student Publications and Presentations
This paper considers the problem of stabilizing a bio-inspired fighter aircraft at its Air Combat Maneuver Condition in steady level and coordinated-turning flight. The aircraft equations of motion are linearized, and an infinite-horizon linear quadratic regulator design is conducted. The open-loop system is unstable in the short period and Dutch roll modes. This is mitigated in the closed-loop system, which is analyzed in the time and frequency domains. Included in the simulation dynamics are first-order actuator models, actuator deflection limits, and actuator rate limits. These are particularly important for this bio-inspired aircraft because control actuation requires rotation of the empennage, …
Circular Dichroism In Achiral Metasurfaces Induced By Spatially Selective Coupling With Molecules, Baojuan Han, Xiaodong Yang, Jie Gao
Circular Dichroism In Achiral Metasurfaces Induced By Spatially Selective Coupling With Molecules, Baojuan Han, Xiaodong Yang, Jie Gao
Mechanical and Aerospace Engineering Faculty Research & Creative Works
Achiral metasurfaces with near-field optical chirality have attracted great attention in molecular sensing and chiral emission control. Here, the circular dichroism (CD) response of an achiral metasurface induced by spatially selective coupling with polymethyl methacrylate (PMMA) molecules is demonstrated. A designed achiral metasurface with a V-shaped resonator exhibits large optical chirality with a strongly dissymmetric distribution under circular polarization. By introducing a PMMA molecule layer on top of the metasurface, which covers the area with large optical chirality, CD in absorption of 0.38 and a dissymmetric factor of optical chirality gc of 0.16 are obtained. Furthermore, an analysis of the …
Design Strategy For Hybrid Thrust Air Bearings: Comparative Analysis Of Rigid Vs. Foil Bearings Considering Optimum Taper Angle And Orifice Location With Experimental Validation, Ehiremen Ebewele
Mechanical and Aerospace Engineering Dissertations - Archive
Gas foil thrust bearings (GFTBs) are contactless bearings that offer advantages such as lightweight construction and the ability to accommodate misalignments and geometric irregularities. However, their load capacity is lower than rigid or magnetic bearings. The structure and geometry of the foil significantly influence GFTB performance. The taper-flat design is the most used configuration due to its effectiveness and ease of implementation. Key parameters in designing this geometry include taper ratio, taper height, orifice size, and orifice location. These parameters must be optimized alongside manufacturing constraints to produce an effective GFTB. This study presents a design optimization investigation of various …
Development Of A Design Tool For Tow-Steered Composite Structures With Machine Learning-Assisted Modeling, Bangde Liu
Development Of A Design Tool For Tow-Steered Composite Structures With Machine Learning-Assisted Modeling, Bangde Liu
Industrial, Manufacturing, and Systems Engineering Dissertations - Archive
Fiber-reinforced composites (FRCs) are widely used in aerospace, automotive, and other engineering applications due to their lightweight characteristics and superior mechanical properties. Traditional FRCs employ a fixed fiber orientation in each layer, and while different layup sequences can tailor performance, the mechanical properties remain spatially uniform. Tow-steered composites, which enable fibers to follow curvilinear paths, offer the potential for spatially varying stiffness and strength, improving structural performance.
This dissertation addresses key challenges in modeling and designing tow-steered composite structures, including the lack of commercial design tools, the high computational cost of design optimization, and the need to efficiently evaluate manufacturing …
Extended-Duration Satellite Testing Via Altitude-Controlled High-Altitude Balloon, Drew Early, Evan Champney, Nikki Allen, Riley Galatis, Lukas Hezel, Joseph Kloess, Andrew Donnell, Sam Whitlock, Kaden Queener
Extended-Duration Satellite Testing Via Altitude-Controlled High-Altitude Balloon, Drew Early, Evan Champney, Nikki Allen, Riley Galatis, Lukas Hezel, Joseph Kloess, Andrew Donnell, Sam Whitlock, Kaden Queener
Von Braun Symposium Student Posters
Undergraduate runner-up, 2025 Von Braun Symposium Student Poster Contest
Numerical Investigation Of Wind Disturbance Around A Multirotor Uav In Crosswind And Vertical Flight, Garrison Page
Numerical Investigation Of Wind Disturbance Around A Multirotor Uav In Crosswind And Vertical Flight, Garrison Page
Theses and Dissertations--Mechanical and Aerospace Engineering
Uncrewed Aerial Vehicles (UAVs) are being increasingly utilized in a wide range of research applications, especially in meteorology. This is due to such factors as their ease of use, maneuverability compared to other forms of data collection, and for rotor- craft, the ability to hover. However, the rotorwash generated by UAVs can introduce significant disturbances, potentially affecting measurement accuracy from sensors. While several studies have investigated the rotorwash of individual UAVs utilizing Particle Image Velocimetry (PIV) and Computational Fluid Dynamics (CFD), there is limited exploration into how different rotor configurations and external wind conditions influence regions of turbulent flow around …
Direct Numerical Simulation Of Pulsating Flow In Curved Pipes: Insights Into Aortic Dissection In Humans, Gokul Anugrah Gopakumar
Direct Numerical Simulation Of Pulsating Flow In Curved Pipes: Insights Into Aortic Dissection In Humans, Gokul Anugrah Gopakumar
Theses and Dissertations--Mechanical and Aerospace Engineering
This dissertation investigates the hemodynamics of pulsating blood flow in curved vessels through direct numerical simulations (DNS), with the overarching aim of uncovering fluid dynamic mechanisms linked to the onset and progression of aortic dissection in humans. The work is structured in two parts: (i) fundamental studies in idealized geometries and (ii) preliminary investigations in patient-specific anatomies. In the first part, curved pipe models representing the aortic arch are used to isolate the effects of pulsation frequency, amplitude ratio, and curvature ratio on transitional and turbulent flow dynamics. The simulations reveal that curvature-driven centrifugal forces shift the peak velocity toward …
High-Altitude Balloon-Launched Uncrewed Aircraft System Measurements Of Atmospheric Turbulence And Qualitative Comparison With Infrasound Microphone Response, Anisa Haghighi
Theses and Dissertations--Mechanical and Aerospace Engineering
This study explores the use of a balloon-launched uncrewed aircraft system (UAS) to measure atmospheric turbulence in the troposphere and lower stratosphere using both wind velocity measurements and infrasonic acoustic energy. The UAS, a glider configured for autonomous descent along a predefined trajectory, had on board, in situ sensors to capture thermodynamic and kinematic atmospheric parameters. Additionally, it carried an infrasonic microphone to evaluate its potential for remotely detecting clear-air turbulence by capturing infrasonic waves. The system’s performance was assessed over the course of three test flights conducted in New Mexico, USA, in 2021. The descent enabled high-resolution profiling, with …
Simulation-To-Hardware Validation Of Mpc For Binary Thruster 2d Cubesat Control, Aevar Amundinusarson Oefjoerd
Simulation-To-Hardware Validation Of Mpc For Binary Thruster 2d Cubesat Control, Aevar Amundinusarson Oefjoerd
Theses and Dissertations--Mechanical and Aerospace Engineering
Small satellites must execute precise, fuel-limited maneuvers under strict actuation and operational constraints. Model Predictive Control (MPC) is a suitable approach because it optimizes future actions while explicitly enforcing these limits. This work evaluates (1) whether MPC can operate in real time using binary (on/off), asymmetric thrusters, and (2) whether a high-fidelity digital twin can be used to tune and validate the controller prior to hardware testing.
An MPC framework was implemented on a planar satellite prototype that floats on air bearings, operates at 16.7 Hz (60 ms period), and uses eight binary thrusters exhibiting up to 13.2% variation in …
Damping Modulation Of Dampened Kapton Surfaces, Sebastian Esteban
Damping Modulation Of Dampened Kapton Surfaces, Sebastian Esteban
Honors Undergraduate Theses
When droplets are vibrated or disturbed, they can exhibit a complex sloshing motion, an understudied behavior in drop physics. Droplet sloshing involves a complex combination of transverse and longitudinal motion that changes the droplet's effective weight on the surface the droplet is on. Our current understanding stems from preliminary work focusing on a cantilever beam of fixed thickness and variable viscosity of the liquid being sloshed. This investigation will focus on how variable cantilever thickness and constant viscosity for a liquid being sloshed affects the beam's deflection under consistent vibration. It will also investigate how the natural frequency of a …
Linking Molecular Structure Evolution To Mechanical Degradation During Environmental Aging In Conventional And Recyclable Epoxy Systems, Ben T. Jewell
Linking Molecular Structure Evolution To Mechanical Degradation During Environmental Aging In Conventional And Recyclable Epoxy Systems, Ben T. Jewell
Dissertations, Master's Theses and Master's Reports
The long-term performance of polymeric materials in extreme environments is governed by complex chemical and physical aging processes that alter their molecular structure and mechanical integrity. Conventional thermoset epoxies, while widely used in structural applications, are particularly susceptible to oxidative degradation at elevated temperatures, leading to embrittlement and loss of structural integrity. In the first part of this work, diffusion-limited oxidation (DLO) in a bulk structural epoxy was systematically investigated to establish the link between heterogeneous microstructural evolution and macroscopic mechanical degradation. High-temperature oxidation experiments were conducted in a controlled environmental chamber, and the resulting chemical, thermal, and mechanical changes …
Drag Reduction In Ground Vehicles Using A Model Porous Medium, Abdullah Ikram Nabi
Drag Reduction In Ground Vehicles Using A Model Porous Medium, Abdullah Ikram Nabi
Master’s Theses
This research investigates aerodynamic drag reduction on a 25° Slanted Ahmed Body (SAB) by integrating porous media model rods through combined experimental and computational methods at a Reynolds number of 1.16×10⁴. Two porous media configurations: short rods (6.75% of the model height) and long rods (20.0% of the model height), both featuring cylindrical rods with 80% porosity, were systematically compared against a baseline SAB. In-depth analyses were performed to investigate the wake flow topology, recirculation region characteristics, pressure coefficient distribution, Reynolds stress distributions and drag coefficient. Experimental investigations employed particle image velocimetry for precise flow visualization, while Reynold Averaged Navier-Stokes …
Smart Material Actuated Flap, James Lyons, Kristofer Johnson
Smart Material Actuated Flap, James Lyons, Kristofer Johnson
Williams Honors College, Honors Research Projects
The objective of this project is to develop and evaluate a smart material actuated aerodynamic control surface to determine the viability of these new systems as alternatives to conventional electromechanical and hydraulic systems. The research will begin with the selection of a control surface and actuator design. The concept will then be tailored to create an experimental model for the purposes of this project. Smart materials that suit the model requirements will be selected and procured. Next, the actuators will be shape trained and characterized to meet the model requirements. Then, a benchtop model will be produced for design verification, …
Effects Of Changes In Strouhal And Reynolds Numbers On Beetle Wing Aerodynamics, Keith L. Thiha
Effects Of Changes In Strouhal And Reynolds Numbers On Beetle Wing Aerodynamics, Keith L. Thiha
Honors Undergraduate Theses
Insect flight has long been a subject of interest across the scientific community, largely due to the exceptional aerodynamic performance insects demonstrate relative to their size. Insects tend to have very high aerodynamic performance characteristics like thrust and lift generation compared to their size. This has many potential applications in improving aircraft performance, however the flow phenomena concerning insect wing aerodynamics is still an area of ongoing research. This study aims to investigate how variations in key nondimensional flow parameters—specifically the Reynolds number and Strouhal number—affect the aerodynamic performance of beetle wings. Strouhal numbers ranging from 0.2 to 0.6 were …
Mechanical And Thermal Characterization Of Additively Manufactured Carbon/Nylon 12 And Carbon/Peek Composites, Matik Heskin, Bradley Deuser, Thomas P. Schuman, K. Chandrashekhara, John Bayldon, Jeff Degrange, Steven Patterson, Neiko Levenhagen
Mechanical And Thermal Characterization Of Additively Manufactured Carbon/Nylon 12 And Carbon/Peek Composites, Matik Heskin, Bradley Deuser, Thomas P. Schuman, K. Chandrashekhara, John Bayldon, Jeff Degrange, Steven Patterson, Neiko Levenhagen
Chemistry Faculty Research & Creative Works
This study explores additive manufacturing of carbon fiber-reinforced thermoplastic composites using the Composite-Based Additive Manufacturing (CBAM) process. Carbon/Nylon 12 and Carbon/PEEK composites were fabricated and evaluated through mechanical (compression, tensile, flexural, and impact) and thermal (DSC and TGA) tests. Carbon/PEEK exhibited superior mechanical performance, with 97.5% higher tensile strength, 79.8% higher elastic modulus, and 59.6% higher flexural strength compared to Carbon/Nylon 12. Thermal testing showed that Carbon/PEEK had higher thermal stability, beginning degradation at 350 °C versus 298 °C for Carbon/Nylon. These results indicate that CBAM-fabricated Carbon/PEEK composites are suitable for applications requiring high strength and temperature resistance.
Numerical Modelling And Co-Optimization Of Gasoline Fuels For Gasoline Compression Ignition Using Multi Component Approach, Ashwin Karthik Purushothaman
Numerical Modelling And Co-Optimization Of Gasoline Fuels For Gasoline Compression Ignition Using Multi Component Approach, Ashwin Karthik Purushothaman
Dissertations, Master's Theses and Master's Reports
Future mobility is expected to rely on a broad spectrum of powertrain technologies, including battery electric vehicles (BEVs), hybrid electric vehicles (HEVs), fuel cell electric vehicles (FCEVs) and traditional internal combustion engine (ICE) vehicles. Despite the shift toward electrification, internal combustion engines are projected to remain a key component of future powertrains, either as the primary power source or as range extenders to generate electricity in hybrid systems. As such, significant research efforts continue to focus on enhancing the efficiency and reducing the emissions of ICEs to meet increasingly stringent regulatory and environmental targets. Gasoline compression ignition (GCI) has been …
Deep Reinforcement Learning-Based Optimal Takeoff Trajectory Design Of An Evtol Drone, Nathan M. Roberts, Bingling Huang, Xiaosong Du
Deep Reinforcement Learning-Based Optimal Takeoff Trajectory Design Of An Evtol Drone, Nathan M. Roberts, Bingling Huang, Xiaosong Du
Mechanical and Aerospace Engineering Faculty Research & Creative Works
The continuing development of electric vertical take-off and landing (eVTOL) aircraft presents promising opportunities to alleviate transportation congestion. However, designing and executing takeoff trajectories that optimally balance energy usage, passenger comfort, and aircraft constraints remains challenging. Conventional design optimization provides a solution for pre-defined flight conditions and environments but is not ideal in real-world applications. In contrast, deep reinforcement learning (DRL) implements optimal policy making real-time decisions with no assumption of mathematical models. Seeing the lack of literature on DRL-based takeoff trajectory design of eVTOL aircraft, we implement and conduct DRL-based optimal takeoff trajectory designs for the Airbus3 Vahana …