Engineering Commons^™

Modeling Of Rotor Wake Vortex Dynamics And Interactions In Non-Homogenous Vertiport Environments, Garrison P. Shaw

Doctoral Dissertations and Master's Theses

The current research serves to analyze and study the effects ground forces can have on the thrust performance of a propeller in multiple different configurations. The current research utilizes an open source Computational Fluid Dynamics (CFD) software known as OpenFOAM to generate calculate and visualize these runs. The model used for this experiment is a hybrid model that employs both a Unsteady Reynolds-Averaged Navier-Stokes (URANS) and a detached eddy simulation using a hybrid Large Eddy Simulation (LES) via a KomegaSSTDDES model. This model serves to save computational time as well as allow for accurate results. The three cases run are …

An Investigation Into In-Flight Loss Of Control Accidents Due To Horizontal Stabilizer Changes On The Piper Cherokee, Connor John Geran

Theses and Dissertations

Loss of Control (LOC) while in-flight in General Aviation (GA) has been the subject of intense research by academic institutions and regulatory agencies in recent years [4] [9] [11] [19] [20] [21]. This interest is primarily due to a disproportionate number of all aircraft accidents occurring within the GA category of flight, with 94% of accidents in 2022 occurring within GA, caused primarily by pilot LOC, with 42% of accidents having LOC as the listed cause. Research into this subject at FIT yielded the results that many common GA aircraft tend to experience a strong pitch up response after undergoing …

Cosmic Object Space Management Operations System (C.O.S.M.O.S.), Riah Ivy, Tyler Bumpus, Gabriel Soter

Senior Design Project For Engineers

In the expansive realm of outer space, humanity has ventured into new territories, yet this progress is accompanied by challenges. Among the most significant challenges confronting space exploration today is the growing amount of space debris within low earth orbit. Satellites, spent rocket stages, and assorted fragments orbiting Earth present a considerable hazard to spacecraft and astronauts, and this issue is steadily worsening. For years, the task of remedying this orbital congestion has remained formidable and unresolved. This design provides a novel and innovative solution to this growing problem.

Experimental And Numerical Analysis Of Laminar And Transitional Flow Through Annular Corrugated Pipes, Joseph Russell Sargent

Theses and Dissertations

This dissertation presents studies on pressure loss through annular corrugated pipes to determine a friction factor coefficient using nitrogen. Ten different corrugated pipes’ geometries were evaluated via testing and experimentation. The ratio of corrugation height to inner diameter varied from 0.233 to 0.333 and the ratio of corrugation pitch to inner diameter varied from 0.181 to 0.446. Nitrogen flow rates between 0.25 to 94.4 standard liters per minute were used, resulting in Reynolds numbers, based on the corrugated pipe inner diameter, from 100 to 23,000. The experimental set-up was validated using smooth-pipe pressure loss measurements and the derived friction factor …

Starfish: A Compact, Biomimetic, And Adaptive Shape Memory Alloy Orbital Debris Remover, Katelyn Branaman

Doctoral Dissertations and Master's Theses

This thesis aims to turn the tides on the orbital debris issue through the fabrication and demonstration of a compact, biomimetic, and adaptive shape memory alloy actuated orbital debris remover. The design, referred to as Starfish, is discussed in detail along with its fabrication process and object capture ability. A hard skeleton crafted from PETG was combined with shape memory alloy wires and extension springs to create a biomimetic structure that operates similar to the human hand, capable of gripping a wide range of objects. Relevant simulations were performed and discussed, the iterative fabrication process used to create each component …

A Comparison Of Western And Eastern Soft Systems Approaches, John L. Anaya, John L. Anaya, John L. Anaya

Master's Theses

Soft System Approaches have been developed worldwide to help problem-solvers and decision-makers develop solutions to complex problems, such as aerospace systems. Soft System Approaches were designed to help lower the disorder of developing a complex system by increasing understanding of a situation. Four Soft System Approaches were investigated, two from the West and two from the East. Within the context of the paper, the West refers to thought patterns associated with thinkers and scientists in Europe and North America, and the East refers to those from and around China. The two from the West are Peter Checkland’s Soft Systems Methodology …

Materials Testing For Large Format 3d Printing, William Jenkins

Williams Honors College, Honors Research Projects

An ABS Carbon Fiber blend was printed into single walled hexagons at a variety of settings on a Cincinnati BAAM large format 3D printer. These hexagons were then cut down into sheets and had tensile and flexural test samples cut out of them, in order for materials testing to be performed. Tensile strength, tensile strain, young’s modulus, flexural strength, deflection and elastic modulus were all determined. A desktop CNC machine and a planer were purchased for the manufacturing of these samples, and an efficient cutting procedure was designed and optimized. After all data collection concluded, this data was thoroughly analyzed, …

Short Strand Carbon Fiber Reinforced Polylactic Acid Filament For Additive Manufacturing, Dale Chenoweth, Lukas Seggi, Luke Phillips

Williams Honors College, Honors Research Projects

In this design project, the additive manufacturing filament of short strand carbon fiber (SSCF) reinforced polylactic acid (PLA) composite was developed. The micro-size, precision cut SSCFs were mixed with the PLA pellets through a melting homogenization process. Through this process the composite material block is cut and divided into pieces for ease of pelletizing. The material block pieces are then pelletized to be fed through the single screw extruder to develop the SSCF-PLA composite filament. The SSCF-PLA filaments were manufactured with a varying amount of SSCF ranging from 0.5% to 10% of the material block's weight. Development of a 1% …

Development Of Load Measurement Technique For Arbitrary Shapes, Quintin J. Cockrell

Master's Theses

Obtaining aerodynamic forces and moments about all three orthogonal axes for arbitrary shapes at arbitrary orientations in a fast manner via a measurement technique specific to Cal Poly’s low-speed wind tunnel to continually obtain the forces and moments under quasi-steady conditions is explored. A Continuous Rotation Technique (CR) uses a 6-DOF load cell and stepper motor to rotate an object about an axis for a complete rotation. The forces and moments acting upon the object pass through the stepper motor and interface plates and recorded by the load cell as the object is rotated continuously a finite number of rotations. …

Neural Network Models For Generating Synthetic Flight Data, Nathaniel Sisson

Doctoral Dissertations and Master's Theses

Flight test data is a valuable resource used in many aerospace applications. However, procuring a sufficiently large database of flight test data poses several challenges. Nominal flight tests can be expensive and time-consuming and require much post-processing depending on the availability of sensors and the quality of the sensor output. Flight test performed outside of nominal flight conditions, or flight tests in which failures are introduced, add to the inherent risk and danger associated with flight tests. The most popular alternative to flight test, numerical simulations, may fail to fully capture all non-linear behavior. While flight tests will always be …

Disc Golf Throwing Robot, Nevada S. Schultz, Sydney M. Lewis, Erick Edmundo Daza, Rachel Alysse Greenberg, Peter M. Kean

Mechanical Engineering

Disc golf companies need better methods to test disc flight. The scope of this project is to create a disc throwing robot that can throw a disc golf driver 450-500 feet, with control over the speed, spin, and release angle. Research shows that multiple disc-throwing products exist; however, none meet the full requirements of this project. The Cal Poly senior project design team created a proof-of-concept machine. This prototype started as a two-wheel mechanism. Eventually, a third wheel was added, allowing for complete control over disc spin. The three-wheel prototype reached 62 mph when perfectly calibrated. The prototype is accurate, …

Enabling Premixed Hydrogen-Air Combustion For Aeroengines Via Laboratory Experiment Modeling, Christopher James Caulfield

Masters Theses

All combustion systems from large scale power plants to the engines of cars to gas turbines in aircraft are looking for new fuel sources. Recently, clean energy for aviation has come into the foreground as an important issue due to the environment impacts of current combustion methods and fuels used. The aircraft industry is looking towards hydrogen as a new, powerful, and clean fuel of the future. However there are several engineering and scientific challenges to overcome before hydrogen can be deployed into the industry. These issues
range from storing the hydrogen in a viable cryogenic form for an aircraft …

Investigation Of Interplanetary Trajectories To Sedna, John W. Sarappo Iii, Samuel Brickley, Iliane Domenech, Lorenzo Franceschetti, James E. Lyne

Chancellor’s Honors Program Projects

No abstract provided.

Nonlinear Dynamics Analysis And Control Of Space Vehicles With Flexible Structures, Marco Fagetti

Doctoral Dissertations and Master's Theses

Space vehicles that implement hardware such as antennas, solar panels, and other extended appendages necessary for their respective missions must consider the nonlinear rotational and vibrational dynamics of these flexible structures. Formulation and analysis of these flexible structures must account for the rigid-flexible coupling present in the system dynamics for stability analysis and control design. The system model is represented by a flexible appendage attached to a central rigid body, where the flexible appendage is modeled as a cantilevered Euler-Bernoulli beam. Discretization techniques, such as the assumed modes method and the finite element method, are used to model the coupled …

Media Streaming In A High-Rate Delay Tolerant Network, Kyle Vernyi

Williams Honors College, Honors Research Projects

Audio and video streaming across delay tolerant networks are relatively new phenomena. During the Apollo 11 mission, video and audio were streamed directly back to Earth using fully analog radios. This streaming capability atrophied over time. The gradual conversion to digital electronics contributed greatly to this. Additionally, 21st century space systems face the new requirement of interconnectedness. Delay Tolerant Networking (DTN) attempts to solve this requirement by uniting traditional point to point links into a robust and dynamic network. However, DTN implementations present bottlenecks due to low performance. High-Rate Delay Tolerant Networking (HDTN) is a performance-optimized DTN implementation. This work …

Development And Implementation Of A Novel Resonantly Ionized Photoemission Thermometry Technique For One-Dimensional Measurements, Walker B. Mccord

Doctoral Dissertations

In this work, Resonantly Ionized Photoemission Thermometry (RIPT) is established and validated as a novel, non-intrusive, non-seeded, One-Dimensional (1D) line thermometry technique. The RIPT technique resonantly ionizes a target molecule via REMPI (Resonant Enhanced Multi-Photon Ionization) of selectively chosen rotational peaks within a resonant absorption band. Thus, efficiently ionizing and subsequently exciting local nitrogen molecules either by direct or indirect schemes. The excited nitrogen deexcites through photoemissions of the first negative band of N₂⁺[molecular nitrogen], specifically near 390, 425, and 430nm [nanometers], that is then acquired as a 1D line signal. The signal strength at all transitions …

Machine Learning To Predict Warhead Fragmentation In-Flight Behavior From Static Data, Katharine Larsen

Doctoral Dissertations and Master's Theses

Accurate characterization of fragment fly-out properties from high-speed warhead detonations is essential for estimation of collateral damage and lethality for a given weapon. Real warhead dynamic detonation tests are rare, costly, and often unrealizable with current technology, leaving fragmentation experiments limited to static arena tests and numerical simulations. Stereoscopic imaging techniques can now provide static arena tests with time-dependent tracks of individual fragments, each with characteristics such as fragment IDs and their respective position vector. Simulation methods can account for the dynamic case but can exclude relevant dynamics experienced in real-life warhead detonations. This research leverages machine learning methodologies to …

Experiments To Mitigate Flow Recirculation In A Closed Anechoic Chamber Using Mesh Screens As Turbulence Suppressors, Tori Kay Wolverton

Theses and Dissertations

The desire to gather acoustic data of a propeller in simulated hover without environmental effects is met with the challenge of recirculating flow in a closed anechoic chamber. Flow recirculation in an anechoic chamber is not ideal because the effects of it being ingested by the rotor cause unsteady loadings on the propeller. This unsteady loading causes vortex noise from the turbulence introduced by the recirculation of the flow. The aim is to study the acoustic signature of a propeller separate from external factors and engine noise. Two different propellers with three different screen combinations were tested in a closed …

Foundations For Finite-State Modelling Of A Two-Dimensional Airfoil That Reverses Direction, Jake Michael Oscar Welsh

McKelvey School of Engineering Theses & Dissertations

Current 3-D finite-state wake models are incapable of simulating a maneuver in which the sign of the free-stream velocity changes direction and the rotor enters its own wake -- as might occur in the case of a helicopter which ascends and then descends. It is the purpose of this work to create a 2-D finite-state wake model which is capable of handling changes in free-stream direction as a precursor to development of a 3-D model that can do the same.

The 2-D finite-state model used for reentry modifications is an existing model created by Peters, Johnson, and Karunamoorthy. By the …

Structural Loads And Preliminary Structural Design For A World Speed Record-Breaking Turbo-Prop Racing Airplane, Matthew G. Slymen

Master's Theses

The Cal Poly SLO Turbo-Prop Racer project aims to design a world speed record-breaking aircraft, capable of flying more than 550 miles per hour on a 3-kilometer closed course. To further this endeavor, this thesis presents the calculations of load distributions across the aircraft’s wing and tail and preliminary structural estimates of primary structural components for verification of the loads calculations and for use in a future finite element model. The aircraft’s fundamental design characteristics effect on the structure of the aircraft, namely the unique Y-tail design, are first examined. Then, loads are calculated in accordance with the regulation dictated …

Application Of The Formal Design Of Experiments To Deformed Airfoil Testing, Alex Ligman

Honors Theses

Traditionally, one factor at a time (OFAT) testing is used to accomplish wind tunnel
experimentation. OFAT testing is a process whereby one of the defined factors in the experiment is changed while all of the other factors are held constant. Afterwards, a new factor is chosen as the one to be manipulated, and the process is then repeated until all factors have been run through. Due to the possible cost-intensive and time-consuming nature of wind tunnel testing, formal design of experiments (DOE) has begun to be applied to wind tunnel experiments. In doing so, unique analyses can be made that …

Pscc Formula Sae Aerodynamic Sub-Team, Nicholas Boccuzzi, Candler Boland, Adam Cain, Michael Palmaccio, Anna "Liece" Tessman

Chancellor’s Honors Program Projects

No abstract provided.

Dynamic Maneuvers For Satellite On-Orbit Servicing Utilizing Novel Continuum Robotics: Development & Experimentation, Nathan Dalton

Masters Theses

Robotic on-orbit servicing is a developing technology that seeks to increase the longevity and repairability of faulty or aging resident space objects. In this research, the development of a flexible continuum manipulator for a small satellite system that performs low-complexity on-orbit servicing or debris removal is presented. Derivations of manipulator kinematics are described in detail, a non-linear control scheme has been developed, and the accuracy and servicing applications for the prototype are evaluated and discussed. The manipulator has been tested on an air-bearing dynamics simulator, and the results are extensively analyzed. System recommendations and future work suggestions are presented.

Online Pilot Model Parameter Estimation For Loss-Of-Control Prevention In Aircraft Systems, Frederick Schill

Doctoral Dissertations and Master's Theses

A pilot is a highly nonlinear and incredibly complex controller whose responses are difficult to predict. Many accidents have occurred from pilot error before or after failures and almost always after entering areas of the flight envelope considered as Loss-of-Control regimes. If a pilot's inputs to the flight control system can be predicted, then the introduction of dangerous flight conditions can be readily avoided. Avoidance could take the form of a warning indicator or augmentation of the pilot's inputs. The primary difficulty lies in how to actually predict how the pilot will perform in the future.

Methods to solve this …

Jcati Carbon Fiber Recycler: Oven Enclosure, Margarita Romero

All Undergraduate Projects

Central Washington University partners with Boeing and is funded by the Joint Center of Aerospace Technology Innovation (JCATI) to develop a mechanism that takes carbon fiber wing trimmings from Boeing that are resin coated and recycles carbon fiber. This is done by crushing the wing trimmings and then putting it into a 500°C oven to melt off the resin. This project focuses on the enclosure for the oven and making sure precautions are met such as having the outside surface be less than 45c through heat transfer analysis, argon fills enclosure in 13 minutes through fluid dynamics analysis, and 99% …

Developing Reactive Distributed Aerial Robotics Platforms For Real-Time Contaminant Mapping, Joshua Ashley

Theses and Dissertations--Electrical and Computer Engineering

The focus of this research is to design a sensor data aggregation system and centralized sensor-driven trajectory planning algorithm for fixed-wing aircraft to optimally assist atmospheric simulators in mapping the local environment in real-time. The proposed application of this work is to be used in the event of a hazardous contaminant leak into the atmosphere as a fleet of sensing unmanned aerial vehicles (UAVs) could provide valuable information for evacuation measures. The data aggregation system was designed using a state-of-the-art networking protocol and radio with DigiMesh and a process/data management system in the ROS2 DDS. This system was tested to …

Fuel System To Envelope Interface, James Campbell

Williams Honors College, Honors Research Projects

*NOTE THIS PROJECT IS CONFIDENTIAL*

In this project, I will investigate solutions to interfacing a fuel system with a fabric skin section

Liquid Engine External Pressurizer (Leep), Emily Armbrust

Williams Honors College, Honors Research Projects

The purpose of this project is to take the current liquid rocket engine test stand design and implement an external pressurant instead of utilizing the 2-phase oxidizer vapor to pressurize itself and the fuel. The purpose behind the design is because the team is limited with the current design concerning burn time due to the amount of propellant they can put in the tanks and the pressure it can reach. The initial pressure is currently not held since there is no external input of mass into the tanks, as the propellant is leaving. Adding an external pressurant allow for the …

Optimal Sizing And Control Of Hybrid Rocket Vehicles, Srija Ryakam

Doctoral Dissertations and Master's Theses

In the present work, a genetic algorithm is used to optimize a hybrid rocket engine in order to minimize the propellant required for a specific mission. In a hybrid rocket engine, the mass flow rate of the oxidizer can be throttled to enhance the performance of the rocket. First, an analysis of the internal ballistics and the ascent trajectory has been carried out for different mass flow rates of the oxidizer as a function of time, for a fixed amount of oxidizer, in order to study the effect of throttling. Two equivalent problems are considered: in the first problem the …

Tradespace Exploration Of A Uav Conceptual Design Using Model-Based Systems Engineering, Ayan Srivastava

All Theses

The objective of this research is to apply model-based systems engineering approaches to the conceptual design of unmanned aerial vehicles. This is accomplished by evaluating the models of aircraft performance, extracting input and output parameters from the models, creating chains of models, and implementing the models in the MATLAB programming language. By following this process, it is possible to identify the global parameters that remain constant across models, the shared input parameters, the dependencies between models, and the feedback loops with the systems models.

The models are currently implemented in two files using Microsoft MS Excel, one is focused on …