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Jeopardy: International Edition
No full textTest your knowledge of world geography, languages, global pop culture, and international firsts—perfect for friendly competition and bragging rights
COE Presents: Italy
No full textExperience Italian culture through food, festive activities, and games that bring the spirit of Italy to campus
Noise Pollution in Daytona Beach: Hurting more than just your Ears
No full textAircraft noise pollution can cause a myriad of negative effects, from sleep disruption and increased annoyance to decreased cognition and problem-solving ability. This is especially relevant at Embry-Riddle Aeronautical University (ERAU). Located right next to an airport producing constant aircraft noise every day, the effects can be felt as far as the ocean, which is located 5 miles away from the airport. Through an intensive literature review, various solutions will be ranked for viability in the Daytona Beach area, and it will be determined which noise mitigation strategy would be the most feasible to implement here. The literature review will be conducted using Google Scholar, and citations will be screened based on credibility of the source and if it underwent a peer review process prior to publication. The solutions will be evaluated based on the mitigation/prevention of noise pollution, their feasibility, and their cost-effectiveness. The aim of this search is to find and evaluate multiple potential solutions that preserve the functionality of the airport while being reasonably economically viable for Daytona Beach and ERAU, as well as decreasing noise pollution to a level at which it is less harmful to life around the airport
International Awards Ceremony
Get PDFA signature celebration of international graduates and study‑abroad achievers, including honors and recognitions that mark global impact and community. The hour-long ceremony will be followed by a reception with light refreshments. All guests of our graduating students, Phi Beta Delta International Honor Society members and inductees, and award nominees are welcome
Brewing Tradition: A Living Art of Tea in China and Japan
No full textA cultural deep‑dive into tea history and ceremony with insights on aesthetics, hospitality, and mindful tasting
IEW Employee Bingo
No full textFor Employees Only A campus‑community game for employees designed to spark cross‑cultural curiosity through quick prompts, fun challenges, and global fact‑finding (prizes and pride included
Propeller Noise Prediction of an Urban Air Mobility Vehicle in Urban Environment
No full textUrban Air Mobility (UAM) vehicles operate in complex, unsteady aerodynamic environments where wake interactions, gust and turbulence significantly affect both performance and noise generation. Understanding these mechanisms is critical for developing quieter and more efficient eVTOL systems that meet future community noise and certification requirements. This dissertation focuses on the high-fidelity numerical investigation of propeller noise in three representative unsteady loading scenarios: (i) transition (tilt) flight, (ii) edgewise inflow, and (iii) wake–propeller interaction. Each case emphasizes different physical mechanisms that dominate noise generation in UAM operations. Hybrid turbulence-resolving approaches—Detached Eddy Simulation (DES) and Delayed Detached Eddy Simulation (DDES)—are coupled with the Ffowcs–Williams and Hawkings (FW–H) acoustic analogy to capture both unsteady flow dynamics and far-field sound radiation.
The first part focuses on the investigation to transition (tilt) flight conditions, where both blade–vortex interaction (BVI) and blade–wake interaction (BWI) mechanisms are also dominant. This section explores the application of the Overset mesh method for propeller simulations in OpenFOAM and compares its performance against the Arbitrary Mesh Interface (AMI) approach in OpenFOAM. While AMI has been extensively validated for rotor acoustics, it is limited in handling large relative motions and interacting components. The Overset method, by contrast, provides greater flexibility for simulating complex transition kinematics through dynamic overlapping grids. However, its effectiveness for aeroacoustic prediction in OpenFOAM has not been previously demonstrated.
To address this gap, a comparative study was conducted for a Joby-scaled five-bladed propeller at an 80° tilt angle without a fairing, representative of a transition-flight condition. Aerodynamic and acoustic analyses were performed using a hybrid DDES coupled with the FW–H formulation. The results show that the Overset method predicts thrust and torque coefficients in closer agreement with experimental data and resolves stronger leading-edge vortices compared to AMI. Both approaches successfully capture leading-edge vortex shedding (LEVS), BVI, and BWI mechanisms. However, the Overset grid exhibits higher BBN levels due to increased vortex intensity and interpolation-induced disturbances, whereas the AMI method provides smoother near-field pressure distributions and clearer tonal responses. In the far field, AMI achieves better tonal agreement with experiments, while Overset demonstrates improved broadband resolution. Overall, the study highlights the complementary strengths of both approaches and underscores the potential of Overset grids for future UAM aeroacoustic simulations involving complex motion and component interaction.
The second part focuses on edgewise flow conditions, representing crosswind or transition phases typical of tilt-rotor and multirotor UAM configurations. A Joby-scaled five-bladed propeller is simulated using DES and the FW–H equation to evaluate physics-based permeable-surface strategies for far-field noise prediction. Various surface configurations—including open-end, closed-end, and end-cap–averaged geometries—are assessed to determine their effects on acoustic accuracy. Comparisons with experimental measurements show that open-ended surfaces significantly underpredict downstream noise due to vortex leakage, whereas closed-end configurations improve prediction accuracy, with 97 % of microphones within 10 dB of the data (compared to 33 % for open-ended). Two correction strategies—JetEnd and SPODEnd—are tested to mitigate spurious low-frequency end-cap noise. Both yield nearly identical results, differing by less than 2.3 dB, indicating that a single end cap is sufficient for accurate prediction. Theoretical analysis and SPOD-based flow decomposition confirm that the proposed convective-spacing model accurately captures the spacing between dominant pressure-fluctuation structures near the propeller tip. This validates the physical basis for end-cap spacing and demonstrates that JetEnd provides a reliable and efficient correction method. Remaining discrepancies for smaller surfaces highlight the need for improved lateral boundary treatments to prevent side-edge vortex contamination. These results collectively establish a validated framework for applying permeable-surface FW–H formulations to UAM propeller noise prediction under edgewise conditions.
The third part of this study extends the investigation to the wake–propeller interaction noise generated by the ingestion of a circular-cylinder wake. The configuration models the effect of a coherent upstream disturbance convected into the propeller disk at a freestream velocity of 20 m/s. The DES-based flow solution captures the unsteady aerodynamic structures within the wake and their interaction with the rotating blades. Coupled FW–H acoustic analysis reveals that wake ingestion leads to strong unsteady blade loading, which decreases thrust and torque while intensifying the hub vortex and promoting complex interactions with tip and trailing-edge vortices. These effects increase vorticity and flow separation in impacted regions. The resulting unsteadiness enhances both tonal and broadband noise components. The Spectral Proper Orthogonal Decomposition (SPOD) analysis shows that tonal noise is dominated by periodic BVI, whereas broadband noise arises from turbulence–wake interactions and the breakdown of coherent structures. The findings confirm that wake ingestion and vortex coupling are key contributors to UAM propeller broadband noise and performance degradation.
Overall, this dissertation advances the understanding of the complex aerodynamic and aeroacoustic mechanisms associated with transition flight, edgewise, and wake ingestion in UAM propellers. The results demonstrate that hybrid LES–URANS methods such as DES and DDES, combined with the FW–H formulation, provide a robust foundation for predicting tonal and broadband noise across a range of unsteady loading conditions. The proposed permeable-surface strategy, end-cap correction model, and AMI-based simulation framework collectively form a scalable methodology for accurate and efficient noise prediction in future UAM design and certification processes
Characterization of Cooled Turbine Efficiency for Off-Design Performance Models
No full textGas turbine performance modeling is essential for predicting engine behavior across design and off-design conditions. Yet the treatment of cooling or service flows remains inconsistent, as these streams interact with the main flow in complex ways and their contribution to turbine work depends on how they are represented in performance models. The challenge is especially present in “black-box” approaches, where only inlet and outlet conditions are known and engineers must decide whether to introduce cooling flows upstream (if performing useful work) or downstream (if not). This thesis examines how different definitions of isentropic power and cooling-flow treatment affect the apparent efficiency of a cooled two-stage axial turbine. A representative numerical model was developed to simulate several service-flow configurations and compare four modeling approaches. Results show that neglecting cooling contributions (Approach A) yields unrealistically high efficiencies, while more refined methods (Approach B, inlet-weighted enthalpy; Approach C, work-potential factors) capture the reduction in available work more accurately. The most rigorous formulation (Approach D, based on Hartsel) applies individual isentropic expansions to each cooling stream and establishes a theoretical lower bound. The study also quantifies the work potential of each cooling stream using literature-based, design-based, and CFD-derived formulations, illustrating how these factors guide the classification of flows as chargeable or non-chargeable in black-box models. Despite the simplified geometry employed, the results offer insight into the sensitivity of turbine efficiency to cooling-flow modeling choices. This work represents a step toward standardized, physically consistent methods for cooled-turbine performance prediction, with future efforts focusing on more realistic geometries, improved mixing models, and integration of the proposed criterion into advanced performance tools
Investigating Driver Perceptions of Semi-Autonomous Vehicle Sensing and Response Characteristics
No full textAs semi-autonomous vehicle (SAV) technologies become increasingly integrated into modern transportation, understanding how the public perceives their capabilities is essential for ensuring safe and effective human-automation interaction. This study examined drivers’ perceptions of SAV detection and discernment abilities across 28 driving conditions and how those perceptions related to expected vehicle behaviors in 17 corresponding scenarios. Exploratory and confirmatory factor analyses identified three perceptual dimensions: Traffic Infrastructure and Vehicle Recognition, Dynamic Roadway Hazards and Vulnerable Road Users, and Human Interaction and Contextual Cues. Moderate overlap between the first two dimensions suggested that participants viewed certain structured and dynamic roadway features as conceptually similar. Structural equation modeling revealed significant relationships between demographic and experiential factors and perceived SAV detection and discernment capabilities, including effects of age, gender, education, total advanced driver assistance systems (ADAS) experience, and self-reported confidence in using ADAS. However, these results should be interpreted cautiously due to weaker overall model fit. Higher confidence in using ADAS predicted stronger agreement with SAV detection and discernment capabilities, while greater experience using ADAS and higher education were associated with more critical evaluations. Across behavioral scenarios, participants generally expected appropriate rule-based responses when they believed detection or discernment was possible, but several cases revealed misalignments between perceived sensing and expected actions. These findings highlight how exposure and confidence interact to shape public expectations of automation and highlight the importance of user education and interface transparency to support safe engagement with SAV technologies
In-Situ Investigations of Calcium-Magnesium-Aluminosilicates (CMAS) Infiltration Effects on Thermal Barrier Coatings Under Extreme Environments Replicating Jet Engines
No full textCalcium-magnesium-aluminosilicate (CMAS) particulates, such as sand or volcanic ash, are ingested by gas turbine jet engines during operation. When operating within high abundance regions, these particulates negatively interact and degrade the high temperature thermal barrier coatings (TBC) protecting underlying superalloy turbine blades vital to engine operation. These CMAS particulates melt within the engine and infiltrate into the ceramic coatings. In electron-beam physical vapor deposited (EB-PVD) TBCs, the CMAS within the intercolumnar gaps stiffens the coatings and causes thermomechanical induced high stress concentrations, risking crack formation. While molten, the CMAS thermochemically alters and destabilizes the coating, also risking coating failure. Premature, localized spallation failure of these ceramic thermal barrier coatings (TBCs) exposes underlying metallic components to the extreme temperatures of the hot gas streams exiting the combustor. Therefore, it is paramount to dynamically capture and characterize the evolution of CMAS infiltration and its reaction kinetics under replicated service conditions and engine environments during operation. In this research, in-situ synchrotron X-ray diffraction measurements were leveraged for the high temporal and spatial resolution it offers, to enable the first known detailed capture of complex, transient micro-mechanisms governing active CMAS infiltration processes of infiltration, interaction, and degradation in a thermal gradient simulated engine environment. The results were analyzed to reveal new knowledge, experimentally showing rapid infiltration of CMAS in less than 2 minutes. The ensuing interaction was characterized and quantified by immediate changes in strain that reveal the thermomechanical effects of stiffening. Meanwhile, thermochemical destabilization of the coating, responsible for enabling the tetragonal to monoclinic phase transformation upon cooling, produced a discernible strain response after a time lag of over 20 minutes and showed most of its effects within the 60 minutes. The accompanying volume change and strain was tracked to show this correlation. Microscale spatial mapping revealed the strong coupling between thermochemical and thermomechanical degradation mechanisms, with the most extensive coating degradation occurred during cooling between 200 - 400 ◦C following infiltration. Upon cooling, the high tetragonal to monoclinic transformation rates induced compressive coating responses up to 2.36x larger than those measured prior to CMAS exposure. Capturing these phenomena elucidates CMAS infiltration wetting behaviors, crack initiation, and pore evolution in coatings exposed to CMAS during realistic flight-representative conditions. These quantitative findings further elucidate the key developmental stages of CMAS-induced degradation, from its time and temperature dependent nucleation to growth stages, and highlights the transient evolution of various reaction-kinetic mechanisms driving degradation throughout a single thermal cycle. These insights will be instrumental in guiding the development of CMAS-resistant coatings and in advancing passive and active CMAS mitigation strategies. In turn, these advancements extend the service life of coating and engine operating in CMAS-rich environments