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Rapid Prediction Of Low-Boom And Aerodynamic Performance Of Supersonic Transport Aircraft Using Panel Methods, Ted N. Giblette Dec 2019

Rapid Prediction Of Low-Boom And Aerodynamic Performance Of Supersonic Transport Aircraft Using Panel Methods, Ted N. Giblette

All Graduate Theses and Dissertations

The Utah State University Aerolab developed and tested a set of tools for rapid prediction of the loudness of a sonic boom generated by supersonic transport aircraft. This work supported a larger effort led by Texas A&M to investigate the use of adaptive aerostructures in lowering sonic boom loudness at off design conditions. Successful completion of this effort will improve the feasibility of supersonic commercial transport over land.

Funding was provided by a NASA University Leadership Initiative grant to several universities, including Utah State University, as well as industry partners to complete this work over a five year period ...


Experimental Investigation Of N2o/O2 Mixtures As Volumetrically Efficient Oxidizers For Small Spacecraft Hybrid Propulsion Systems, Rob L. Stoddard Dec 2019

Experimental Investigation Of N2o/O2 Mixtures As Volumetrically Efficient Oxidizers For Small Spacecraft Hybrid Propulsion Systems, Rob L. Stoddard

All Graduate Theses and Dissertations

A hybrid thruster system utilizes propellants in two different stages, traditionally a solid fuel and a gaseous or liquid oxidizer. Recently hybrid thrusters have become a popular topic of research due to the high demand of a ”green” replacement for hydrazine. Not only are hybrid thruster systems typically much safer than hydrazine, but they are also a low-cost system with a high reliability in performance. The Propulsion Research Laboratory (PRL) at Utah State University (USU) has developed a hybrid thruster system using 3-D printed acrylonitrile butadiene styrene (ABS) as the fuel and gaseous oxygen (GOX) as the oxidizer. This system ...


Calibration Of Hot-Film X-Probes For High Accuracy Angle Alignment In Wind Tunnels, Dallin L. Jackson Aug 2019

Calibration Of Hot-Film X-Probes For High Accuracy Angle Alignment In Wind Tunnels, Dallin L. Jackson

All Graduate Theses and Dissertations

This thesis investigates the use of hot-film thermal anemometers to align a plate on a wind tunnel at Hill Air Force Base that is used to calibrate Angle of Attack Transmitters on F-16s. A reoccuring problem with this wind tunnel is that no two instruments can verify an angle reading of the the mounting plate for the Angle of Attack Transmitters to the air stream in the wind tunnel. Multiple thermal anemometer calibration methods, such as Jorgensen’s equation and a look-up table are implemented to attemp to achieve consistent measurements between multiple probes. The results show that it is ...


Isentropic Efficiency And Theoretical Analysis Of The Planetary Rotor Expander, Joseph L. James Aug 2019

Isentropic Efficiency And Theoretical Analysis Of The Planetary Rotor Expander, Joseph L. James

All Graduate Theses and Dissertations

Expanders allow pressurized fluids to undergo a pressure decrease in a controlled environment via volumetric growth to extract fluid energy. There are many types of expanders, and the objective of this thesis is to model the efficiencies of the planetary rotor expander (PRE), a century-old design undeveloped due to insufficient manufacturing capabilities (until recently). Geometric relationships are derived and mathematical models are generated to determine the efficiency of the PRE as a function of design variables. Two industrially relevant case studies show that, to maximize isentropic efficiency, the planetary rotor expander (PRE) rotational frequency is maximized and rotor geometry optimized.


How Vision Governs The Collective Behaviour Of Dense Cycling Pelotons, J. Belden, Mohammad M. Mansoor, A. Hellum, S. R. Rahman, A. Meyer, C. Pease, J. Pacheco, S. Koziol, Tadd T. Truscott Jul 2019

How Vision Governs The Collective Behaviour Of Dense Cycling Pelotons, J. Belden, Mohammad M. Mansoor, A. Hellum, S. R. Rahman, A. Meyer, C. Pease, J. Pacheco, S. Koziol, Tadd T. Truscott

Mechanical and Aerospace Engineering Faculty Publications

In densely packed groups demonstrating collective behaviour, such as bird flocks, fish schools or packs of bicycle racers (cycling pelotons), information propagates over a network, with individuals sensing and reacting to stimuli over relatively short space and time scales. What remains elusive is a robust, mechanistic understanding of how sensory system properties affect interactions, information propagation and emergent behaviour. Here, we show through direct observation how the spatio-temporal limits of the human visual sensory system govern local interactions and set the network structure in large, dense collections of cyclists. We found that cyclists align in patterns within a ± 30° arc ...


A Multi-Fidelity Prediction Of Aerodynamic And Sonic Boom Characteristics Of The Jaxa Wing Body, Forrest L. Carpenter, Paul G. A. Cizmas, Christian R. Bolander, Ted N. Giblette, Doug F. Hunsaker Jun 2019

A Multi-Fidelity Prediction Of Aerodynamic And Sonic Boom Characteristics Of The Jaxa Wing Body, Forrest L. Carpenter, Paul G. A. Cizmas, Christian R. Bolander, Ted N. Giblette, Doug F. Hunsaker

Mechanical and Aerospace Engineering Student Publications and Presentations

This paper presents a detailed comparison between the linear panel solver PANAIR A502 and the in-house Navier–Stokes solver UNS3D for a supersonic low-boom geometry. The high-fidelity flow solver was used to predict both the inviscid and laminar flow about the aircraft geometry. The JAXA wing body was selected as the supersonic low-boom geometry for this study. A comparison of the undertrack near-field pressure signatures showed good agreement between the three levels of model fidelity along the first 0.8L of the signature. Large oscillations in the PANAIR results were observed. The PANAIR discrepancies were traced back to violations ...


Water Walking As A New Mode Of Free Surface Skipping, Randy C. Hurd, Jesse Belden, Allan F. Bower, Sean Holekamp, Michael A. Jandron, Tadd T. Truscott Apr 2019

Water Walking As A New Mode Of Free Surface Skipping, Randy C. Hurd, Jesse Belden, Allan F. Bower, Sean Holekamp, Michael A. Jandron, Tadd T. Truscott

Mechanical and Aerospace Engineering Faculty Publications

Deformable elastomeric spheres are evaluated experimentally as they skip multiple times over a lake surface. Some spheres are embedded with small inertial measurement units to measure the acceleration experienced during water surface impact. A model for multiple impact events shows good agreement between measured acceleration, number of skipping events and distanced traveled. The experiment reveals a new mode of skipping, “water walking”, which is observed for relatively soft spheres impacting at low impact angles. The mode occurs when the sphere gains significant angular velocity over the first several impacts, causing the sphere to maintain a deformed, oblong shape. The behavior ...


Developing Silent Unmanned Aerial Vehicles, Glen Wright Mar 2019

Developing Silent Unmanned Aerial Vehicles, Glen Wright

Research on Capitol Hill

The optimization of a drone propeller’s acoustic signature can play an important role in the Department of Defense, observation of nature, commercial operations, and marine propulsion.

The aim of this research is to optimize the acoustic signature of propellers by isolating and modifying specific propeller characteristics. Propeller variations being researched in this project include:

  • Leading-edge serrations: break up incoming fluid and evenly disperse it along airfoil
  • Trailing-edge serrations: minimize vortex occurrences along the trailing edge of airfoil
  • Airfoil ribs: force fluid through tangential channels along airfoil
  • Winglets: disrupt turbulence and vortices at the tips of the propeller

Successful drone ...


A Sine-Summation Algorithm For The Prediction Of Ship Deck Motion, Christian R. Bolander, Douglas F. Hunsaker Jan 2019

A Sine-Summation Algorithm For The Prediction Of Ship Deck Motion, Christian R. Bolander, Douglas F. Hunsaker

Mechanical and Aerospace Engineering Student Publications and Presentations

Landing a fixed-wing aircraft on a moving aircraft carrier is a risky and inefficient process. Having an accurate prediction of ship deck motion decreases the risk posed to both the pilot and the aircraft and increases the efficiency of landing maneuvers. The present work proposes the use of a sine-summation algorithm to predict future ship motion. The algorithm decomposes recorded ship acceleration data into its characteristic harmonic parameters using a fast Fourier transform. The harmonic parameters are then used in a summation of sine waves to create a fit for the acceleration data, which is projected into future time intervals ...


A Procedure For The Calculation Of The Perceived Loudness Of Sonic Booms, Christian R. Bolander, Douglas F. Hunsaker, Hao Shen, Forrest L. Carpenter Jan 2019

A Procedure For The Calculation Of The Perceived Loudness Of Sonic Booms, Christian R. Bolander, Douglas F. Hunsaker, Hao Shen, Forrest L. Carpenter

Mechanical and Aerospace Engineering Student Publications and Presentations

Implementing a method to calculate the human ear’s perceived loudness of a sonic boom requires consulting scattered literature with varying amounts of detail. This work describes a comprehensive implementation of Stevens’ Mark VII in Python, called PyLdB. References to literary works are included in enough detail so that the reader could use this work as a guide to implement the Mark VII algorithm. The details behind the mathematics of the Mark VII algorithm are included and PyLdB is used to calculate the perceived loudness of an example pressure signature. PyLdB is benchmarked against a widely used and validated code ...