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Articles 1 - 28 of 28
Full-Text Articles in Propulsion and Power
Zfq-50 "Radiance", Craig Slovensky, Michael Rath Iii, Kyan Spaete, Long P. Nguyen, Woo Hyun Lee, Roman Czerniejewski
Zfq-50 "Radiance", Craig Slovensky, Michael Rath Iii, Kyan Spaete, Long P. Nguyen, Woo Hyun Lee, Roman Czerniejewski
Discovery Day - Daytona Beach
This project presents the preliminary design of the ZFQ-50 "Radiance", a Collaborative Unmanned Vehicle (CUV) built around the VerdeGo VH-5 blended turbofan intended for military defense applications. This design presents a novel aircraft coupled with a powerplant that blends traditional combustion thrust with electrical power output, an new and evolving capability within the aerospace industry. This aircraft was sized considering multiple constraint parameters, configuration trade studies, CFD analysis, and mission requirements including carrier assisted take-off and landing, an effective operational range, and a loiter period with 40 kW of continuous power output from the powerplant. The selected configuration allows for …
Stabilized Cargo Relay Aircraft For Precision Payload Yielding, Dato A. Tabidze, Michael Conely, Ben Courtney
Stabilized Cargo Relay Aircraft For Precision Payload Yielding, Dato A. Tabidze, Michael Conely, Ben Courtney
Senior Design Project For Engineers
As military missions become more complicated, warfighters need more capable drones to use across diverse scenarios. The same also applies to civilian applications, like infrastructure inspection, package delivery, and disaster response. Current multirotor drones, also known as unmanned aircraft systems (UAS), provide simplicity, affordability, and ease of operation; however, their primary limitation is their low payload-to-weight ratio, which typically falls at 1:1 or less. The DARPA Lift Challenge aims to shatter the heavy lift bottleneck, seeking novel drone designs that can carry payloads more than four times their weight, which would revolutionize the way we use drones across all sectors. …
Conceptual Exploration Of Film Cooling Techniques In Hydrogen Gas Turbines, Wen Wu
Conceptual Exploration Of Film Cooling Techniques In Hydrogen Gas Turbines, Wen Wu
Student Research Symposium (SRS)
Film cooling is a key heat transfer technique that protects gas turbine blades from extreme temperatures, allowing higher turbine inlet temperatures and greater thermal efficiency. It works by ejecting a thin layer of cooler air from the compressor through small holes onto the hot surface, creating a protective film layer that lowers surface temperature and reduces thermal stress on blades. This process is vital in power generation and propulsion systems that operate near material limits. With growing emphasis on sustainability, film cooling has gained new importance in hydrogen-fueled gas turbines. Hydrogen combustion creates water vaper and low-density exhaust gases, which …
Methodologies And Applications Of Precision Shot Peening To Hole Or Slot Geometry, James C. Hoffman
Methodologies And Applications Of Precision Shot Peening To Hole Or Slot Geometry, James C. Hoffman
15th International Conference on Shot Peening
Shot peening, a commonly used method of fatigue and surface enhancement, is a critical process in many of the components in the aerospace industry. When it comes to small holes and/or slot geometries in these components, the process can become a challenge when these features are smaller than a conventional size Almen strip. In these cases, a decision must be made about how to process this type of geometry. Oftentimes, the method to apply the shot peen process is already defined in a process specification or part print so we must adhere to that method. If a method is not …
Improving Fatigue Strength And Life Of Single Crystal Cmsx-4, Jochen Peter Fuhr, Lloyd Hackel, Nicolau I. Morar, Noah Holtham, Keivan Davami, Montu Sharma, Rajkumar Roy
Improving Fatigue Strength And Life Of Single Crystal Cmsx-4, Jochen Peter Fuhr, Lloyd Hackel, Nicolau I. Morar, Noah Holtham, Keivan Davami, Montu Sharma, Rajkumar Roy
15th International Conference on Shot Peening
The deep penetration of laser peening (LP) and retention of residual stress at high temperature by LP is significant in improving fatigue life and strength of superalloys exposed to high temperature and corrosion. Single crystal CMSX-4, was evaluated for stress relaxation and both fatigue life and fatigue strength of material that was LP-treated compared to non-LP and shot-peened (SP) specimens. LP was done with multiple layers using a 20 J/pulse laser where the laser high energy enabled using a 5 mm spot size on the metal surface. Stress measurements by the slitting technique showed the plastic penetration depth exceeded SP …
Model-Based Design Of Compressed Lithium-Metal Pouch Cell Battery Modules For Evtol Applications, Scott J. Stirling
Model-Based Design Of Compressed Lithium-Metal Pouch Cell Battery Modules For Evtol Applications, Scott J. Stirling
Master's Theses
Batteries with higher specific energy and power are essential for extending the range and performance of electric vertical takeoff and landing aircraft (eVTOLs). Anode-free lithium-metal pouch cells offer strong potential at the cell-level but require high compressive pressures to enhance cycle life and discharge performance. These pressures necessitate heavier structural components, reducing packaging efficiency at the module level.
To evaluate this tradeoff, a full-factorial enumeration model was developed to explore viable module designs within a constrained packaging volume. The model scales subsystem masses, enforces design rules and material limits, and accounts for large (~20%) cell thickness changes during cycling.
Results …
Novel Design And Fabrication Of A High-Speed Transient Heat Flux Sensor For Application To Rotating Detonation Engines, Zachary Todd Tallman
Novel Design And Fabrication Of A High-Speed Transient Heat Flux Sensor For Application To Rotating Detonation Engines, Zachary Todd Tallman
Graduate Theses, Dissertations, and Problem Reports (ETD)
Rotating detonation engine (RDE) combustion systems have been a topic of interest in the pressure gain combustion community for their benefits over traditional gas turbine engine combustors. However, cooling requirements for these engines are significantly higher and less predictable than those of non-detonating engines. To understand and quantify the high-speed heat transfer dynamics within an RDE, a novel high-frequency heat flux sensor is presented. This study aims to design a robust, single-sided sensor that can withstand the high temperature and harsh environment of an RDE for extended durations. Screen printing is used to deposit a layered, platinum-yttria-stabilized zirconia (YSZ) film …
Uav To Carry Heavy Loads, Jacob Cannon, Robert Connor Downs, Anthony Orlando
Uav To Carry Heavy Loads, Jacob Cannon, Robert Connor Downs, Anthony Orlando
Williams Honors College, Honors Research Projects
Our senior design project aims to develop an innovative Unmanned Aerial Vehicle (UAV) capable of carrying heavy payloads up to 50 lbs. This UAV will address the growing demand for efficient and autonomous cargo transportation, unlocking new possibilities in logistics and remote deliveries. The primary goal is to design, build, and test a robust UAV platform equipped with advanced propulsion systems, stabilizing mechanisms, and a secure payload attachment system. The heavy-lift UAV will be capable of transporting payloads in challenging environments, enhancing its versatility for various industries, including emergency response, disaster relief, and commercial logistics. For the extent of this …
Kwad - Ksu All Weather Autonomous Drone, Nick Farinacci, Sebastian Gomez, Stewart Baker, Ed Sheridan
Kwad - Ksu All Weather Autonomous Drone, Nick Farinacci, Sebastian Gomez, Stewart Baker, Ed Sheridan
Symposium of Student Scholars
"KWAD" or "KSU all-Weather Autonomous Drone" project was sponsored by Ultool, LLC to the KSU Research and Service Foundation to create a lightweight drone capable of capturing HD video during all-weather operations. The conditions of all-weather operation include rainfall of one inch per hour and wind speeds of up to twenty miles per hour. In addition, a global minimum structural safety factor of two is required to ensure the system's integrity in extreme weather conditions. Potential mission profiles include autonomous aerial delivery, topological mapping in high moisture areas, security surveillance, search and rescue operations, emergency transportation of medical supplies, and …
Superfly Amphibian, Devonte Andrews, Ahmed Hamza, Kwesi Onumah, Eva Sanchez
Superfly Amphibian, Devonte Andrews, Ahmed Hamza, Kwesi Onumah, Eva Sanchez
Senior Design Project For Engineers
Following a Short Takeoff and Landing (STOL) mission profile, this seaplane is designed to carry 19 passengers and 1 flight crew with a range of 200 nautical miles. The seaplane is equipped with two turbo-prop engines and is economically comparable to current seaplanes in terms of servicing and operating expenses. The aircraft is capable of operating in remote locations with limited infrastructure due to its STOL abilities, allowing for increased access to difficult-to-reach areas. The seaplane's design incorporates modern materials and technologies to enhance efficiency, safety, and comfort for passengers and crew. The aircraft's versatility and cost-effectiveness make it an …
Lupa: An Excursion Vehicle For The Moons Of Mars, Shannon Kavanagh, Bo Lewis, Alex Odinamba, Joshua Mulhern
Lupa: An Excursion Vehicle For The Moons Of Mars, Shannon Kavanagh, Bo Lewis, Alex Odinamba, Joshua Mulhern
Senior Design Project For Engineers
Our team has designed a spacecraft and mission for exploring the moons of Mars. The Lithological and Ultraviolet Photometry Assessment (LUPA) excursion vehicle is capable of crew habitation, autonomous rendezvous, and in-vacuum sample collection all in support of a parallel Mars surface mission to be carried out in the year 2040. Our project's key focus areas revolve around orbital mechanics, space vehicle propulsion analysis, scientific exploration, and the management of various interconnected spacecraft subsystems.
Development Of High-Density Propulsion System Technologies For Interplanetary Small Satellites And Cubesats, Morgan Andrew Roddy
Development Of High-Density Propulsion System Technologies For Interplanetary Small Satellites And Cubesats, Morgan Andrew Roddy
Graduate Theses and Dissertations
The goal of this research was to support the development of a novel propulsion system for small satellites (<180 kg) and CubeSats. This was pursued by conducting a collection of studies that were designed to provide engineering data that would be critical in designing a functional prototype. The novel propulsion system was conceived by the author to provide best-in-class performance for the small satellite and CubeSat families of spacecraft. This context presents specific design requirements that the presented technology attempts to satisfy. The most critical among these is high density; the propellant was designed to be stored with high density and the thruster was designed to be as compact as possible. The propulsion system is composed of two primary elements, a propellant generator and a thruster. The propellant generator works by sublimating a solid crystal into vapor and then using this vapor to etch a dense metal. The resulting gaseous byproducts of this reaction are the propellant. This dissertation used xenon difluoride (XeF2) vapor to etch tungsten (W) which react to form xenon gas (Xe) and tungsten hexafluoride (WF6). This approach gave a theoretical propellant storage density 5.40 g/cm3; and 5.17 g/cm3 was demonstrated. The sublimation dynamics of the XeF2 were studied as a function of surface area and temperature and it was found to be suitable for the intended application due to its high effluence rate; that is, it sublimates fast enough to be useful. The sublimation rates are on the order of 10’s of µg/s. The etch rate of XeF2 on W was also studied and found to be suitably fast to provide useful amounts of reactants for use as a propellant, again on the order of 1’s of µg/s. The thruster is an electrostatic radio frequency (RF) ion thruster design and is manufactured with Low Temperature Co-Fired Ceramic (LTCC) materials system and manufacturing technology. Manufacturing samples of the thruster were built at the University of Arkansas in July 2015 and tested at NASA’s Marshall Space Flight Center in May 2018. Testing validated the viability of the LTCC thruster and provided valuable information on how to improve the thruster’s design.
Studies Of Oval Tube And Fin Heat Exchangers, Phillip Nielsen
Studies Of Oval Tube And Fin Heat Exchangers, Phillip Nielsen
Undergraduate Student Works
Heating Ventilation and air-conditioning (HVAC) is a system which changes the temperature of the surroundings for the purposes of cooling or heating. This system requires energy to maintain a temperature difference from the outside temperature. Optimizing the flow over the evaporator coils is one way to increase the cooling efficiency. This will reduce the power required to have a sustainable system. Optimizing the flow to increase the energy transfer between the fins and the incoming air could result in a greater Coefficient of Performance (COP). This will be achieved by changing the geometry of the tubes for greater interaction with …
Sae Aero West Heavy Lift Competition Team - Eaglenautics, Anthony Pirone, Evan Stuart, Jessica Millard, Nathaniel Scott
Sae Aero West Heavy Lift Competition Team - Eaglenautics, Anthony Pirone, Evan Stuart, Jessica Millard, Nathaniel Scott
Discovery Day - Prescott
ERAU’s SAE Aero Design West Competition team encourages students of all majors who have an interest in the design of heavy-lift cargo and passenger aircraft to design, build, and fly a large RC aircraft to meet a new set of regulations each competition year. Since the team, Eaglenautics, was founded in 2017 it has successfully been to competition once in April 2019 in California. The team’s aircraft flew 4 out of 5 flight rounds, passed all technical inspections, and is now on display in ERAU’s Aero-Fab in the AXFAB. The 2020 competition requirements are unique in that the cargo’s weight-to-volume …
Rocket Motor Nozzle, Corey Hillegass
Rocket Motor Nozzle, Corey Hillegass
Williams Honors College, Honors Research Projects
For this honors research and senior design project, the authors will research, analyze, and manufacture a rocket motor nozzle for the Akronauts rocket design team. This research and design project will improve how the rocket design team will decide and manufacture nozzles going forward. The impact of this improvement allows the rocket design team to take steps toward being self-sustaining by manufacturing student designed parts as opposed to commercially bought parts. This will not only be successful in increasing student impact on future designs, but also provides a technical challenge for the authors and will present as an impressive feat …
Performance Enhancement And Characterization Of An Electromagnetic Railgun, Paul M. Gilles
Performance Enhancement And Characterization Of An Electromagnetic Railgun, Paul M. Gilles
Master's Theses
Collision with orbital debris poses a serious threat to spacecraft and astronauts. Hypervelocity impacts resulting from collisions mean that objects with a mass less than 1g can cause mission-ending damage to spacecraft. A means of shielding spacecraft against collisions is necessary. A means of testing candidate shielding methods for their efficacy in mitigating hypervelocity impacts is therefore also necessary. Cal Poly’s Electromagnetic Railgun was designed with the goal of creating a laboratory system capable of simulating hypervelocity (≥ 3 km/s) impacts. Due to several factors, the system was not previously capable of high-velocity (≥ 1 km/s) tests. A deficient projectile …
Improving The Delivered Specific Impulse Of Composite Rocket Propellant Through Alteration Of Chemical Composition: Methodology And Parameters For Characterization Of Propellant And Validation Of Simulation Software Common To The Amateur Rocketry Community, Isaac O'Brien, Austin Ryan
Williams Honors College, Honors Research Projects
In this study, two solid composite rocket propellants were designed utilizing ProPEP, a rocket propellant formulation software common in the amateur and hobby rocketry communities. The two propellants were designed to optimize specific impulse relative to a literature propellant designed by 1020 Research Labs. The literature propellant was also tested in order to validate the design of experiment as well as the mixing and testing procedures. All three propellants, which includes the literature propellant RCS-P, and the two novel propellants AKR-P1 and AKR-P2 were characterized with static tests. The results of the static tests provide data on propellant performance and …
Optimal Sintering Temperature Of Ceria-Doped Scandia Stabilized Zirconia For Use In Solid Oxide Fuel Cells, Amanda K. Assuncao
Optimal Sintering Temperature Of Ceria-Doped Scandia Stabilized Zirconia For Use In Solid Oxide Fuel Cells, Amanda K. Assuncao
Honors Undergraduate Theses
Carbon emissions are known to cause decay of the Ozone layer in addition to creating pollutant, poisonous air. This has become a growing concern among scientists and engineers across the globe; if this issue is not addressed, it is likely that the Earth will suffer catastrophic consequences. One of the main culprits of these harmful carbon emissions is fuel combustion. Between vehicles, power plants, airplanes, and ships, the world consumes an extraordinary amount of oil and fuel which all contributes to the emissions problem. Therefore, it is crucial to develop alternative energy sources that minimize the impact on the environment. …
Constructal Alkaline Membrane Fuel Cell (Amfc) Design, E. M. Sommer, J. V. C. Vargas, Lauber De Souza Martins, J. C. Ordonez
Constructal Alkaline Membrane Fuel Cell (Amfc) Design, E. M. Sommer, J. V. C. Vargas, Lauber De Souza Martins, J. C. Ordonez
Faculty Publications
This paper introduces a structured procedure to optimize the internal structure (relative sizes, spacing) and external shape (aspect ratios) of a single alkaline membrane fuel cell so that net power is maximized. The optimization of flow geometry is conducted for the smallest (elemental) level of a fuel cell stack, i.e., the single alkaline membrane fuel cell, which is modeled as a unidirectional flow system. The polarization curve, total and net power, and efficiency are obtained as functions of temperature, pressure, electrolyte solution concentration (KOH), geometry and operating parameters. The optimization is subjected to fixed total volume. There are two levels …
The Robert & Esther Goddard Papers, Robert H. Goddard
The Robert & Esther Goddard Papers, Robert H. Goddard
Finding Aids
Dr. Robert H. Goddard was a member of the Clark Physics Department for 29 years. Foremost American pioneer of rocket research, he laid the technical and theoretical foundations for many of the developments in long-range rockets, missiles, satellites and space flight, which collectively put us into the Space Age.
The collection includes correspondence, diaries, journals, patent applications and awards, reports, and photographs. The collection also includes original paintings by Dr. Goddard.
Hybrid Rocket Motor Scaling Process, Joseph B. R. Vanherweg
Hybrid Rocket Motor Scaling Process, Joseph B. R. Vanherweg
Master's Theses
Hybrid rocket propulsion technology shows promise for the next generation of sounding rockets and small launch vehicles. This paper seeks to provide details on the process of developing hybrid propulsion systems to the academic and amateur rocket communities to assist in future research and development. Scaling hybrid rocket motors for use in sounding rockets has been a challenge due to the inadequacies in traditional boundary layer analysis. Similarity scaling is an amendment to traditional boundary layer analysis which is helpful in removing some of the past scaling challenges. Maintaining geometric similarity, oxidizer and fuel similarity and mass flow rate to …
Suborbital Spaceflight: A Student Team’S Plan To Send A Rocket To Space, Bryce Chanes, William Carpenter, Julio Benavides, Matthew Haslam, Brenda Haven
Suborbital Spaceflight: A Student Team’S Plan To Send A Rocket To Space, Bryce Chanes, William Carpenter, Julio Benavides, Matthew Haslam, Brenda Haven
Aviation / Aeronautics / Aerospace International Research Conference
The Eagle Space Flight Team was created with the goal of becoming the first undergraduate team to design, build, and launch a rocket capable of suborbital spaceflight. In order to achieve this goal, the team will have to design a rocket capable of atmospheric flight at speeds over Mach 5 and launch it on one of the largest amateur rocket motors ever made. Over the next three years, the team will progress towards accomplishing this feat through a series of incremental test flights. Before the space flight, the team will build three sub-scale rockets designed to reach altitudes of 30,000’, …
Design Of The Structural And Propulsion Systems For The 2015 University Of Akron Rocket Team, Kyle W. Dehoff, Nicholas J. Hrusch
Design Of The Structural And Propulsion Systems For The 2015 University Of Akron Rocket Team, Kyle W. Dehoff, Nicholas J. Hrusch
Williams Honors College, Honors Research Projects
No abstract provided.
Achieving Global Range In Future Subsonic And Supersonic Airplanes, Nihad E. Daidzic Ph.D., Sc.D.
Achieving Global Range In Future Subsonic And Supersonic Airplanes, Nihad E. Daidzic Ph.D., Sc.D.
International Journal of Aviation, Aeronautics, and Aerospace
No commercial airplane in service today is able to fly half great-circle distances over the globe and achieve the non-stop or the global range to any antipodal location on Earth. A subsonic jetliner has the optimum cruising speed at Mach numbers approaching the drag divergence Mach number while still preserving relatively high aerodynamic efficiency. Various fuel-flow laws were used to investigate the cruise performance of subsonic and supersonic aircraft. The effect of wind and aircraft weight and how it affects the optimal cruising airspeed was investigated. Of all different operational cruising techniques, the cruise-climb at high Mach numbers is the …
Feasibility Analysis For Electrically-Powered Hoverboard, Cameron Chan, Jason Cortez, Jay Lopez
Feasibility Analysis For Electrically-Powered Hoverboard, Cameron Chan, Jason Cortez, Jay Lopez
Aerospace Engineering
Composite materials are engineered by combining two or more constituent materials with significantly different physical or chemical properties in such a way that the constituents are still distinguishable, and not fully blended. Due to today’s high rising prices of gasoline and aviation fuel costs, many manufacturers have turned to the use of lightweight composites in their designs due to the advantages of the composite material, which include outstanding strength, excellent durability, high heat resistance, and significant weight reduction that the composite material properties hold. The purpose of this project is to design and construct a composite structure for an electrically-powered …
Design, Manufacturing And Testing Of An Environmentally-Green Bipropellant Thruster, Alex Bendoyro, Gabriel Sanchez, Erin Stearns, Phillip Takahashi
Design, Manufacturing And Testing Of An Environmentally-Green Bipropellant Thruster, Alex Bendoyro, Gabriel Sanchez, Erin Stearns, Phillip Takahashi
Aerospace Engineering
This project reviews the design, manufacturing and experimentation process of a green bi-propellant thruster designed to output 5 lbf. The goals were to successfully design, manufacture and test a thruster, while discovering the complications that arise through out the complete design process of a green thruster. The thruster was successfully designed using ideal rocket equations and the design was successfully confirmed using CFD and FEA. Manufacturing of the thruster was fully planned and revealed mild flaws in thruster design. For example some features were not manufacturable to the exact measurements desired. Testing of the engine gave results inconsistent with expected …
Multidisciplinary Design Optimization Of An Extreme Aspect Ratio Hale Uav, Bryan J. Morrisey
Multidisciplinary Design Optimization Of An Extreme Aspect Ratio Hale Uav, Bryan J. Morrisey
Master's Theses
ABSTRACT
Multidisciplinary Design Optimization of an Extreme Aspect Ratio HALE UAV
Bryan J. Morrisey
Development of High Altitude Long Endurance (HALE) aircraft systems is part of a vision for a low cost communications/surveillance capability. Applications of a multi payload aircraft operating for extended periods at stratospheric altitudes span military and civil genres and support battlefield operations, communications, atmospheric or agricultural monitoring, surveillance, and other disciplines that may currently require satellite-based infrastructure. Presently, several development efforts are underway in this field, including a project sponsored by DARPA that aims at producing an aircraft that can sustain flight for multiple years and …
Optimization Of Zero Net-Mass Flow Actuators For Aero-Optics Applications, Moira L. Denatale, Jonathan M. Mihaly
Optimization Of Zero Net-Mass Flow Actuators For Aero-Optics Applications, Moira L. Denatale, Jonathan M. Mihaly
Renée Crown University Honors Thesis Projects - All
Using experimental methods, zero net-mass flow actuators were optimized to manipulate flow around an airborne laser turret in order to reduce destructive aero-optics effects. Synthetic jets are created by 50 mm and 27 mm piezoelectric disk actuators. Our optimization process involved identifying an actuator’s cavity size, driving frequency, and amplitude to achieve the strongest, most consistent jet possible. The effects of driving a single actuator versus driving two actuators in or out of phase with one another were also investigated. An initial cavity depth was determined using the Helmholtz resonator cavity approximation which estimates the ideal cavity depth for a …