Mechanical Engineering Commons^™

Sensitivity Study Regarding Abs Formulation On Hybrid Rocket Performance, Ava T. Wilkey, Ryan J. Thibaudeau, Stephen A. Whitmore

Mechanical and Aerospace Engineering Student Publications and Presentations

Acrylonitrile butadiene styrene (ABS) has emerged as a widely adopted solid fuel for hybrid rocket propulsion due to its compatibility with fused deposition modeling and favorable regression characteristics. As a terpolymer, however, ABS monomer mass fractions vary across commercial sources, introducing thermochemical variability that is rarely accounted for in propulsion modeling. This study presents a sensitivity analysis examining how compositional variability among ten commercially available ABS feedstock propagates into hybrid rocket performance predictions. Each source was characterized using bomb calorimetry and Fourier-transform infrared spectroscopy to derive source-specific constituent mass fractions and enthalpies of formation, which were supplied to NASA’s Chemical …

Sensitivity Analysis Of A Low-Power Wireless Capacitive Charging System To Inform Thermal Limitations And Battery Size Reduction Potential For Electric Passenger Vehicles, Karmen Teuscher

All Graduate Theses and Dissertations, Fall 2023 to Present

The purpose of using electric vehicles instead of internal combustion engine vehicles that burn gas is to reduce pollutants in the air and potential environmental impacts such as climate change. EVs produce much less air pollutants than ICEVs but manufacturing the EV batteries and the repeated recharging still contributes to the overall air pollution.

Capacitive power transfer systems can wirelessly charge vehicles through the road as they drive along highways or stop at traffic lights. If vehicles charge as they drive, an opportunity opens to reduce the size of the battery while maintaining the same driving range. Reducing the size …

Toward Risk-Informed Design Of Supercooling Heat Exchangers: Statistical Inference And Experimental Investigation Of Heterogeneous Ice Nucleation, Daniel B. Gardner

All Graduate Theses and Dissertations, Fall 2023 to Present

Ice-based cooling storage systems can reduce electricity costs and grid strain by making ice during off-peak hours and using it for air conditioning during the day. One promising design works by chilling water below its freezing point as it flows through a heat exchanger, then allowing it to freeze in a separate storage tank. The challenge is that the chilled water can freeze prematurely inside the heat exchanger itself, blocking the flow and shutting the system down. Preventing this unwanted freezing requires understanding how and where ice begins to form on surfaces, a process called nucleation.

This dissertation investigates ice …

A Cfd-Dem Framework For Characterizing Nanoparticle Adhesion Effects On Creeping-Flow Permeability In Composite Manufacturing, Gavin Stoker

All Graduate Theses and Dissertations, Fall 2023 to Present

Modern aircraft, spacecraft, and high-performance vehicles are increasingly built from composite materials, engineered combinations of plastics and fibers that are lighter and stronger than traditional metals. Researchers are now pushing these materials further by mixing in microscopic particles thousands of times smaller than a human hair, called nanoparticles, to make them even tougher and more resistant to damage. The challenge is getting those nanoparticles distributed evenly. During manufacturing, liquid plastic resin is pumped through a network of tightly packed fibers, carrying the nanoparticles along with it. But nanoparticles tend to clump together and stick to surfaces as they travel, clogging …

High-Throughput Characterization Of Creep In Additively Manufactured 316l Stainless Steel, Raushan Kumar Singh

All Graduate Theses and Dissertations, Fall 2023 to Present

Advanced materials are widely used in industries such as nuclear energy, aerospace, and automotive engineering, where components are exposed to extreme temperatures and stresses over long periods of time. As new materials continue to emerge, researchers need efficient ways to evaluate their mechanical performance so they can be used safely and effectively. Among several mechanical challenges, creep is a major concern in these conditions. Creep is a type of mechanical failure in which materials gradually deform when exposed to high temperatures and constant load. Conventional methods for evaluating creep typically involve testing a single specimen at a time, which can …

Theory, Implementation, And Practical Applications Of A Modern Parabolized Navier-Stokes Code, Logan B. Freeman

All Graduate Theses and Dissertations, Fall 2023 to Present

The Parabolized Navier-Stokes (PNS) method is a specialized computational approach for solving the equations that govern fluid flowing faster than the speed of sound, known as supersonic flow. By leveraging unique physical properties of supersonic environments—specifically that information cannot travel upstream—this method allows for significantly more efficient calculations than traditional approaches. Supersonic flows are important for many military and civilian applications including hypersonic weapons, high-speed passenger aircraft, and reentry. This thesis provides a comprehensive review of the two-dimensional PNS formulation, detailing the mathematical derivation and its practical implementation for solving flow problems. Through performance analysis and error assessment, this research …

Nozzle Erosion Reconstruction Model For Data Analysis In Rocket Engines And Correlation With Chamber Pressure, Ryan J. Thibaudeau, Stephen A. Whitmore

Mechanical and Aerospace Engineering Student Publications and Presentations

Graphite nozzles remain the dominant choice for small hybrid and solid rocket motors operating on laboratory and university budgets, owing to their low cost, ease of machining, and rapid turnaround during iterative design campaigns. These same programs, however, must contend with the fact that graphite erodes through coupled thermochemical and mechanical mechanisms when exposed to the oxidizing species generated by high-energy propellant combustion, and the resulting throat-area growth fundamentally alters the time histories of chamber pressure, thrust, and delivered specific impulse. This paper presents a nozzle-erosion reconstruction model that extracts the time-resolved throat area from coupled thrust and chamber-pressure measurements …

A Provable Semi-Infinite Programming Approach For Solving Constrained Dynamic Games, Tyler C. Gardner, Matthew W. Harris, Logan Lancaster

Mechanical and Aerospace Engineering Student Publications and Presentations

Many engineering problems must account for the non-cooperative decisions and actions of multiple players. These problems can be modeled within a game-theoretic framework. The approach herein is to model such problems as mathematical games, convert them to semi-infinite programs, and utilize a semi-infinite program solver whose output is provably an ϵ-optimal Nash equilibrium. The approach is successfully benchmarked on two low-dimensional problems. Two types of higher-dimensional linear quadratic dynamic games are then investigated: ones where each player’s problem is convex and ones where at least one player’s problem is nonconvex. Within each type, variations based on information structure, control …

Automating Building Feature Recognition In Digital Twin Models Using Computer Vision, Jaron Harbison

Undergraduate Honors Capstone Projects

Standard 3D scans treat all surfaces as generic geometry, but Wi-Fi signals don't. A signal drops by a different magnitude through a wooden door than a concrete wall. Without labeling these materials, Internet Service Providers (ISPs) cannot accurately predict "dead zones". This project addresses that gap by creating a machine learning model that identifies structural and architectural features. This includes features such as walls, doors, windows, and columns directly from RGB-D (Red, Green, Blue, Depth) point cloud data. 

I constructed the model on a custom U-Net architecture featuring a symmetric encoder-decoder structure with skip connections, trained on the StructScan3D dataset …

Tau Beta Pi Engineering Mentorship Program, Tyler Black

Undergraduate Honors Capstone Projects

The purpose of this project is to design and implement a student-led engineering mentorship program directed by the members of the Utah Gamma Chapter of Tau Beta Pi on the Utah State University (USU) Logan campus. Retention data show that many undergraduate students who start engineering programs change their degree before graduation due to academic and social challenges that may be mitigated by the support of a peer mentor. The Tau Beta Pi Engineering Mentorship Program selects and trains upperclassman mentors to effectively mentor underclassman engineering students.

The design of the mentorship program is an application of backward design, where …

Ngc - Torch Test Ablation Stand Improvements And Upgrades, Sarah Nelson

Undergraduate Honors Capstone Projects

This capstone project is sponsored by Northrop Grumman (NGC). The goal of the project is to redesign an ablation torch testing system to improve usability, safety, and versatility. Northrop Grumman relies on their ablation torch testing system to conduct quantitative evaluations of materials and high stress and high temperature conditions. The system provides essential data that supports product development, safety validation, and compliance with performance standards. By improving usability, safety, and versatility, NGC will be able to streamline testing operations, increase accuracy of results, and reduce operator risk. The system must allow testing using both a bent and straight torch …

Aerodynamic Parameter Estimation For A Scaled F-16: A Simulation-Based Sensitivity Analysis, Kathle C. Tischner

All Graduate Theses and Dissertations, Fall 2023 to Present

The physical motion of an aircraft is determined by the resulting forces and moments acting on the aircraft. These forces and moments can be defined as a mathematical equation where the control deflections, rotation rates, and orientation of the aircraft are multiplied by individual constants and summed together to define the entire force or moment. This method results in a highly accurate model that defines the motion of the aircraft at low angles of attack and sideslip. Initial calculations of the aerodynamic model are created based on analytical estimations based on the physical properties of the aircraft. Additional refinement of …

Development Of A Novel Method For Simultaneously Testing Multiple Specimens To Evaluate Tension-Tension Fatigue Life, Mehedi Hasan Mahfuz

All Graduate Theses and Dissertations, Fall 2023 to Present

The aim of this study is to develop a novel method for rapidly evaluating the tension–tension fatigue life of metals. Fatigue failure, which occurs when materials gradually weaken and fracture under repeated loading, is a critical concern in designing safe and reliable structures such as airplanes, cars, and bridges. Traditional fatigue testing methods are slow, costly, and typically limited to one specimen at a time. To address this, a high-throughput testing method was developed that allows multiple small-scale specimens to be tested simultaneously while following international testing standards. Using stainless steel sub-sized specimens scaled at 1:5 relative to the ASTM …

Two Applications Of Lifting-Line Theory For The Design Of Efficient Aircraft, Amanda K. Olsen

All Graduate Theses and Dissertations, Fall 2023 to Present

Numerical lifting-line is a tool that can be used to evaluate the forces and moments of an aircraft wing. This method has limitations but it is beneficial in obtaining a large set of results with relatively little computational power. This research seeks to analyze two different flight scenarios through the use of two numerical lifting-line tools developed at the Utah State University AeroLab. The first scenario involves an aircraft in ground effect flight. When an aircraft flies close to the ground, a phenomenon called ground effect occurs where the lift is increased and the induced drag is decreased. Therefore, flying …

Developing And Improving Digital Image Correlation (Dic) Techniques For Challenging Environments, Prasenjit Dewanjee

All Graduate Theses and Dissertations, Fall 2023 to Present

Understanding how materials and parts deform during testing is crucial for creating safer and more reliable engineering systems. Engineers need to measure not only how much a part deforms, but also where deformation concentrates before any damage or failure happens. Digital image correlation (DIC) is a camera-based, non-contact measurement method that tracks surface motion and deformation across a whole area. It is particularly useful when traditional contact-based measurement techniques cannot withstand harsh conditions or capture enough detail. This dissertation develops optical methods to improve DIC in three challenging measurement situations. First, a shortwave ultraviolet lighting technique is developed to reduce …

Numerical Investigation On Lightning Survivability And Residual Strength Of Scarf-Patched And Z-Pinned Cfrp Composites, Logan Hales

All Graduate Theses and Dissertations, Fall 2023 to Present

Carbon fiber reinforced polymer (CFRP) composites are critical in aerospace applications yet remain vulnerable to lightning strikes due to orthotropic electrical conductivity and poor thermal resistance. Over the past decades, lightning-strike damage in pristine CFRP has been extensively investigated. However, the response of damaged and subsequently repaired laminates remains poorly understood, raising concerns about the structural integrity of repaired aircraft. This study aims to develop a sequentially coupled thermo-structural modeling framework to quantify how two common composite repair strategies (scarf patching and z-pinning), along with patch size, pin material, and configuration, influence lightning-induced damage and the residual flexural strength of …

Hypersonic Impact Method For Aerodynamics And Convective Heating (Hi-Mach) With Sensitivities, Jeremiah Goates, Logan Freeman, Nathan Hoch, Douglas Hunsaker

Mechanical and Aerospace Engineering Student Publications and Presentations

The purpose of this paper is to present the development of an engineering level code for calculating hypersonic aerodynamics and convective heating, HI-Mach. Novel to this paper are the use of analytic methods for streamline tracing and the direct differentiation of geometric sensitivities for both forces and heat load. Independent panel inclination methods calculate the pressure distribution on the surface of a hypersonic vehicle. Normal shock relations provide the thermodynamic state on each panel. Streamlines are integrated using closed-form streamline equations. Flat plate formulas corrected for compressibility calculate the skin friction coefficient and acreage heat flux on each panel. Formulas …

Further Development Of A Low-Energy Arc-Ignition System For Nytrox/Abs Hybrid Propulsion Systems, Stephen A. Whitmore, Jared S. Coen, Ryan J. Thibaudeau

Mechanical and Aerospace Engineering Faculty Publications

Utah State University has developed a high-performance “green” hybrid propulsion technology based on the unique electrical breakdown properties of 3D-printed acrylonitrile butadiene styrene. Using 3D-printed ABS as fuel, typical startup sequences require approximately 5–15 joules and, once started, the system can be sequentially fired with no additional energy inputs required. The number of possible ignitions is limited only by the amount of fuel. The most technologically mature version uses gaseous oxygen (GOX) as oxidizer and 3D-printed ABS as fuel. While GOX is mass-efficient, it lacks volumetric efficiency unless highly pressurized. Nytrox, a blend of GOX and nitrous oxide, improves propellant …

Supporting Data For Novel Approach For Quantifying The Impact Of Coherent Structures On The Turbulent Kinetic Energy Decay Rate, Tim Berk, Ankit Gautam

Browse all Datasets

This project investigates the influence of coherent structures on the decay of turbulent kinetic energy (TKE). The work was conducted as part of the PhD research in Mechanical Engineering by Ankit Gautam at Utah State University.

Simulation Study On Nh3 Combustion And NoX Emissions Under Gas Turbine-Relevant Conditions, Kumeesha Arumawadu, Braxton Wiggins, Ziyu Wang

Mechanical and Aerospace Engineering Student Publications and Presentations

Ammonia (NH₃) is a zero-carbon fuel and an attractive hydrogen (H₂) carrier for gas turbine power generation due to its high energy density, ease of storage, and transportation. This study numerically investigates NH₃/air combustion using a hybrid Well-Stirred Reactor (WSR) and Plug Flow Reactor (PFR) model in Cantera at pressures of 1–20 atm, temperatures of 1850–2150 K, and equivalence ratios (ϕ) of 0.7–1.2. The effects of pressure, equivalence ratio, and temperature on NH₃ conversion and NO formation are examined. Results show that NH₃ exhibits a non-monotonic conversion curve with pressure after the …

Measurement Uncertainty, Barton L. Smith, Douglas R. Neal

Mechanical and Aerospace Engineering Textbooks

This text is based on the graduate Measurements course notes from BLS at Utah State University. It is intended as a textbook for graduate students in engineering or physics or as a reference text.

If one collects several texts on measurement uncertainty, it quickly becomes clear that the measurement uncertainty community lacks a consistent language or nomenclature. This can be confusing to a new reader who may view measurement uncertainty as a very old and settled topic. The lack of consensus on nomenclature likely stems from the lack of a clear winner–a paradigm and nomenclature set sufficiently superior to be …

Grain Size- And Temperature-Dependent Phonon-Mediated Heat Transport In The Solid Electrolyte Interphase: A First-Principles Study, Arjun S. Kulathuvayal, Yanqing Su

Mechanical and Aerospace Engineering Student Publications and Presentations

The solid electrolyte interphase (SEI) is a passive layer, typically a few hundred angstroms thick, that forms on the electrode surface in the first few battery cycles when the electrode is in contact with the electrolyte in lithium-metal batteries. Composed of a combination of lithium salts and organic compounds, the SEI plays a critical role in battery performance, serving as a channel for Li-ion shuttling. Its structure typically comprises an inorganic component-rich sublayer near the electrode and an outer organic component-rich sublayer. Understanding heat transport through the SEI is crucial for improving battery pack safety, particularly since the Li-ion diffusion …

Exploring Methods For Quantifying Uncertainty In Neural Network-Based Turbulence Closures, Cody Grogan

All Graduate Theses and Dissertations, Fall 2023 to Present

Machine Learning (ML) is a very promising field for data-driven modeling of different phenomena. In the field of Computational Fluid Dynamics (CFD), ML is an enticing alternative to traditional methods to improve the accuracy and computational efficiency of simulations. However, many ML models, like Neural Networks, don’t quantify their uncertainty or indicate their confidence in a prediction to those who wish to use them. This is especially important because the use of inaccurate ML predictions in a CFD simulation can greatly impact the validity of a simulation. However, with uncertainty quantification, an ML model can indicate to a modeler the …

A Provable Semi-Infinite Programming Approach For Solving Dynamic Nash Games, Tyler C. Gardner

All Graduate Theses and Dissertations, Fall 2023 to Present

Many engineering problems must account for the non-cooperative decisions and actions of multiple players. These problems can be modeled within a game-theoretic framework. The approach herein is to model problems as Nash games, convert them to semi-infinite programs, and leverage provable semi-infinite algorithms to solve the original problem. A particular algorithm that leverages off-the-shelf solvers is used to solve four low-dimensional benchmark problems successfully. Two types of linear quadratic dynamic games are then investigated: ones where each player’s problem is convex and ones where at least one player’s problem is nonconvex. Within each type, variations based on information structure, communication …

An Optimization Study Of Multi-Orifice Synthetic Jets, Rhett T. Parry

All Graduate Theses and Dissertations, Fall 2023 to Present

From the mixing of creamer into coffee, to the dynamics of a dust storm, or smoke rising from a chimney—everything is driven by turbulent fluid motion. Experimentalists bring the complex driving mechanism that is turbulence into a laboratory setting to fundamentally understand its behavior in response to certain test parameters. Researchers may choose various drivers, or “actuators”, of fluid motion to start the turbulent regime for their applications. However, in building an entire experimental apparatus, they miss the step of ensuring that an individual driver is performing as best as possible. A common actuator used in experimental studies is a …

Analysis Of Thrust Performance And Noise Generation Of Uam Composite Propellers Fabricated Using Composite-Based Additive Manufacturing, Samiul Alam

All Graduate Theses and Dissertations, Fall 2023 to Present

Urban air mobility (UAM) is an emerging transportation concept that uses lightweight, efficient aircraft for transporting goods and passengers and performing other logistical activities. One of the biggest challenges in developing UAM from a structural perspective is manufacturing strong and reliable propellers that are lightweight and durable. Traditional manufacturing methods for composite propellers are expensive, time-consuming, and difficult to scale. This study explores a new approach using Composite-Based Additive Manufacturing (CBAM) to produce high-performance propellers more efficiently. CBAM allows for the fabrication of strong, lightweight composite propellers using short manufacturing lead times. However, one challenge with this technique is that …

Bonding Ss316l And In625 Through Laser Powder Bed Fusion And Directed Energy Deposition: A Comparative Tensile Analysis, Christopher J. Bettencourt, Nadia Kouraytem

Mechanical and Aerospace Engineering Student Publications and Presentations

Directed Energy Deposition (DED) was used to deposit Inconel 625 (IN625) onto 316L stainless steel (SS316L) substrates fabricated by Laser Powder Bed Fusion. Tensile properties of the resulting multi-material specimens were compared to those of the individual alloys. Two bonding approaches were evaluated: a direct transition and a 50/50 intermediate layer formed by blending equal parts of each alloy during deposition. The multi-material specimens demonstrated higher yield strength than the single alloys. However, samples with the 50/50 transition exhibited brittle failure at the joint, whereas the direct transition behaved more ductile. Scanning Electron Microscopy revealed microcracks at the interface of …

The Potential Of Microbial Fuel Cells As A Dual Solution For Sustainable Wastewater Treatment And Energy Generation: A Case Study, Shajjadur Rahman Shajid, Monjur Mourshed, Md. Golam Kibria, Bahman Shabani

Mechanical and Aerospace Engineering Student Publications and Presentations

Microbial fuel cells (MFCs) are bio-electrochemical systems that harness microorganisms to convert organic pollutants in wastewater directly into electricity, offering a dual solution for sustainable wastewater treatment and renewable energy generation. This paper presents a holistic techno-economic and environmental feasibility assessment of largescale MFC deployment in Dhaka’s industrial zone, Bangladesh, as a relevant case study. Here, treating 100,000 cubic meters of wastewater daily would require a capital investment of approximately USD 500 million, with a total project cost ranging between USD 307.38 million and 1.711 billion, depending on system configurations. This setup has an estimated theoretical energy recovery of 478.4 …

Designing And Modeling An Exoskeleton Mobility Device For Individuals With Paraplegia, Dan O'Crowley

All Graduate Reports and Creative Projects, Fall 2023 to Present

The objective of this project is to design and develop a lightweight mobility exoskeleton for individuals with paraplegia that enables transportation of the user in a standing position, supports the user during the sitting to standing transition, and can be loaded by the user into a vehicle. A device like this has the potential to mitigate many negative health impacts of seated mobility devices, reduce social barriers, increase job opportunities for the user, and improve independence, while providing cost savings for the users and the healthcare system.

The system consists of a 3-linkage inverted pendulum with motors at the knee …

Bomb Calorimeter As Proof Of Concept For Low-Cost Calorimeter To Measure Thermal Runaway In Pouch Cells To Facilitate Statistical Characterization, Mykell Johnson

All Graduate Reports and Creative Projects, Fall 2023 to Present

Transportation is becoming increasingly electrified, with the main energy storage system being lithium-ion (li-ion) batteries. Despite the widespread adoption of li-ion batteries, unique design abuse tolerance concerns need to be addressed, specifically regarding the catastrophic exothermic release of energy, called thermal runaway (TR). While TR is a major design consideration in all li-ion applications, it presents unique difficulties in the electric aviation industry. The Federal Aviation Administration (FAA) considers thermal runaway inevitable in a battery pack and requires containment of the event per DO311-A for certified aircraft. Due to the wide variability of TR, designing for this phenomenon can be …