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Sae Aero West Heavy Lift Competition Team - Eaglenautics, Anthony Pirone, Evan Stuart, Jessica Millard, Nathaniel Scott 2020 Embry-Riddle Aeronautical University

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 …


Launch Vehicle Design For The Far-Mars Competition, Matthew Boban, Bryce Smoldon, Jonathan Noble, Stefan Johnson, Maxwell Kauker, Nicholas Wright, Andrew Lucka 2020 Embry-Riddle Aeronautical University

Launch Vehicle Design For The Far-Mars Competition, Matthew Boban, Bryce Smoldon, Jonathan Noble, Stefan Johnson, Maxwell Kauker, Nicholas Wright, Andrew Lucka

Discovery Day - Prescott

Zenith Propulsion is constructing a launch vehicle, named Altair, to compete in a competition hosted by the Friends of Amateur Rocketry (FAR) and the Mars Society. The objective for Zenith Propulsion is to design, build and launch Altair to a qualifying altitude of 30,000 feet in the FAR-Mars competition. Altair will utilize a rocket engine that has been in development at Embry-Riddle Aeronautical University’s Prescott campus since late 2018. This engine, named Janus, uses liquid oxygen and Jet-A and is designed to deliver 1000 lbf of thrust. Altair will be launched from the FAR launch site, in Mojave, CA, on …


Development Of A Small Scale Rotating Detonation Engine, Joseph R. Dechert 2020 Air Force Institute of Technology

Development Of A Small Scale Rotating Detonation Engine, Joseph R. Dechert

Theses and Dissertations

The Rotating Detonation Engine (RDE) has been researched extensively in recent years, but the minimum size limits of an RDE have not been well investigated. The goal of this research was to build an RDE small enough to produce a detonation frequency above 20 kHz with a single detonation wave while also reducing the engine's mass ow rate. An engine with these design characteristics would reduce hazards associated with previous RDE testing. This research objective resulted in the design of an RDE with an outer diameter sized at 28 mm using ethylene and nitrous oxide as a fuel and oxidizer. …


Design And Analysis Of A Compact Combustor For Integration With A Jetcat P90 Rxi, Daniel Holobeny 2020 Air Force Institute of Technology

Design And Analysis Of A Compact Combustor For Integration With A Jetcat P90 Rxi, Daniel Holobeny

Theses and Dissertations

Ultra Compact Combustors are a novel approach to modern gas turbine combustor designs that look to reduce the overall combustor length and weight. A previous study integrated an Ultra Compact Combustor into a JetCat P90 RXi turbine engine and achieved self-sustained operation with a length savings of 33% relative to the stock combustor. However, that combustor could not operate across the full stock engine performance range due to flameout at increased mass ow rates as reactions were pushed out of the primary zone. To ensure reactions stayed in the primary zone, a new design with a larger combustor volume was …


Detonation Confinement In A Radial Rotating Detonation Engine, Kavi Muraleetharan 2020 Air Force Institute of Technology

Detonation Confinement In A Radial Rotating Detonation Engine, Kavi Muraleetharan

Theses and Dissertations

Radial Rotating Detonation Engines (RRDE) have provided an opportunity for use of a pressure-gain combustor in a more compact form compared to an axial RDE. A successfully tested RRDE has operated over a wide range of test conditions and produced detonation modes with one, two, and three waves. The presence of multiple waves located the detonation waves to the outer radius, while one wave modes operated closer to the inner radius. Locating the detonation wave closer to the inner diameter resulted in less time for combustion prior to the radial turbine. Subsequently, this tended to decrease efficiency. To attempt to …


Microturbine Turbojets: Experimental Evaluation Of Commercially Available Engines, Richard A. DePaola III 2020 Air Force Institute of Technology

Microturbine Turbojets: Experimental Evaluation Of Commercially Available Engines, Richard A. Depaola Iii

Theses and Dissertations

This research assessed the performance of commercial microturbine turbojets and was the first industry-wide investigation into this class of engine by AFRL's SERL. Four commercial engines of the same thrust class were evaluated for overall and component-level performance. In addition to providing an evaluation of existing systems, the maximum performance for a commercial turbojet was predicted based on component evaluations. This analysis indicated that a commercial turbojet could have comparable thrust performance to a similarly sized military-grade engine, but it is unlikely that commercial engines can achieve the SFC of military engines without upgrading the compressors found in commercial microturbines.


Communication In Fluid Medium Using Motor Modulation, Brian Butka, Jefferson Romney 2020 Embry-Riddle Aeronautical University

Communication In Fluid Medium Using Motor Modulation, Brian Butka, Jefferson Romney

Publications

Aquatic vehicles may use electric motors for propulsion, such as brushless motors. As an example, a speed of these motors can be controlled using a pulse-width-modulated (PWM) electrical signal that varies the motor speed by varying pulse parameters within the PWM signal. PMW modulation can cause the motor to emit significant acoustic noise into the environment. In a fluid medium, such as aquatic environment, such noise can be detected with hydro­phones or other acoustic sensors. The subject matter described herein can include modulating a signal provided to a motor to provide a communication signal to be mechani­cally (e.g., acoustically) emitted …


Assessment And Applications Of The Conversion Of Chemical Energy To Mechanical Energy Using Model Rocket Engines, Hüseyin Sarper, Nebojsa I. Jaksic, Ben J. Stuart, Karina Arcaute 2020 Old Dominion University

Assessment And Applications Of The Conversion Of Chemical Energy To Mechanical Energy Using Model Rocket Engines, Hüseyin Sarper, Nebojsa I. Jaksic, Ben J. Stuart, Karina Arcaute

Mechanical & Aerospace Engineering Faculty Publications

To provide the first-year engineering students with a hands-on experience in an engineering application using both chemistry and physics, this team project uses a set of chemical and physical energy concepts and MS Excel based analysis. The main objective of the project is to calculate how much of the potential maximum possible chemical energy is converted into propulsion when using model rocket engines with solid fuel. The secondary objective is to determine the effects of increasing conversion rates on the performance of a model rocket. The solid fuel or propellant used in common model rocket engines is black powder. Compared …


Generation Of Premix Laminar Flame Speed Library, Sai Prashanth Kumar 2020 Michigan Technological University

Generation Of Premix Laminar Flame Speed Library, Sai Prashanth Kumar

Dissertations, Master's Theses and Master's Reports

The Laminar flame speed is an essential parameter in measuring turbulent premixed combustion applied in Spark ignition engines. Instead of using power-law correlations, which is valid only for particular ranges, the procedure for generating a premixed laminar flame speed library is defined using MTU – Master mechanism for a wide range of charge mixture conditions inside an engine combustion chamber: Temperature (300 – 700 K), Pressure (1 – 70 bar) and reactant mixture composition of equivalence ratio (0.4 – 2.0) Laminar flame speed library is generated for methane. The mechanism's performance was improved by adjusting the pre-exponential factor of the …


Parametric Study Of A Turbojet Engine With Auxiliary Bypass Combustion- The Turboaux Engine, Kaleab Fetahi, Sharanabasaweshwara A. Asundi, Arthur C. Taylor, Adem H. Ibrahim, Syed Firasat Ali 2020 Old Dominion University

Parametric Study Of A Turbojet Engine With Auxiliary Bypass Combustion- The Turboaux Engine, Kaleab Fetahi, Sharanabasaweshwara A. Asundi, Arthur C. Taylor, Adem H. Ibrahim, Syed Firasat Ali

Mechanical & Aerospace Engineering Faculty Publications

A parametric study of a novel turbojet engine with an auxiliary combustion chamber, nicknamed the TurboAux engine is presented. The TurboAux engine is conceived as an extension of a turbojet engine with an auxiliary bypass annular combustion chamber around the core stream. The study presented in this article is motivated by the need to facilitate clean secondary burning of fuel at temperatures higher than conventionally realized from air exiting the low-pressure compressor. The parametric study is initiated by performing a simple optimization analysis to identify optimal ‘fan’ pressure ratios for a series of conventional low-bypass turbofan engines with varying bypass …


Flame Stabilization Of A Premixed Jet In Vitiated Coflow, Tyler Owens 2020 University of Kentucky

Flame Stabilization Of A Premixed Jet In Vitiated Coflow, Tyler Owens

Theses and Dissertations--Mechanical Engineering

Premixed staged combustion in gas turbine engines can reduce emissions by lowering peak flame temperatures but can also lead to different stability characteristics when compared to traditional combustors. High pressure ratio and subsequently high temperatures can lead to conditions suitable for both autoignition and premixed flame propagation in an environment where spatial fuel/air variations are present.

An experimental facility which issues a premixed jet into a coflowing vitiated mixture was studied to examine the stability behavior, resulting in a lifted flame. The effective ignition delay observed flame was much greater than homogeneous ignition delay calculations for the same conditions. It …


Performance Characteristics Design Of Pulsed Plasma Thrusters For Drag Counter-Reacting, Dr. Sam Dakka 2020 The University of Nottingham

Performance Characteristics Design Of Pulsed Plasma Thrusters For Drag Counter-Reacting, Dr. Sam Dakka

International Journal of Aviation, Aeronautics, and Aerospace

Determining the performance characteristics of off the shelf pulsed plasma thrusters to enhance the life time of low earth orbiting platforms was investigated theoretically. Pulsed plasma thruster analysis was accomplished through development of correlations from historical data that distinguished between breech fed propellant to side fed propellant designs. Based on semi-empirical equations the power required by the thruster to counter react the drag was estimated and mapped for 1U to 27U CubeSat configurations for altitude ranging between 200km to 600km. It appears that the power required is dependent on the feeding delivery system design. For side fed designs the power …


Active Fault-Tolerance Of The Unmanned Aerial Vehicle Automatic Control Systems, Vuong Anh Trung, Nguyen Van Thinh, Nguyen Duc Thanh, Nguyen Quang Vinh, Tran Thuan Hoang 2020 Air Defense - Air Force Academy, Son Tay, Ha Noi, Viet Nam

Active Fault-Tolerance Of The Unmanned Aerial Vehicle Automatic Control Systems, Vuong Anh Trung, Nguyen Van Thinh, Nguyen Duc Thanh, Nguyen Quang Vinh, Tran Thuan Hoang

International Journal of Aviation, Aeronautics, and Aerospace

This paper presents an introductory overview of principles of the three-layer hierarchy of active fault-tolerance, providing, determination of the fault type with as many details as enough to get recoverable fault reason and failure toleration by flexible redundancy using; the conception of active fault-tolerant control in abnormal modes is described. Developed models and methods of a systematic approach to fault tolerance in the direction of the effective use of the signal, parametric and structural redundancies and selection of parrying tools. Performed experimental researches of the unmanned aerial vehicle (UAV) automatic control systems (ACS).


Rocket Motor Nozzle, Corey Hillegass 2020 The University of Akron

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 …


Supersonic Propulsion: Inlet Shock Wave/Boundary Layer Interaction In A Diffuser, Lucas Fulop, Ian Henry, Jordan Ruffner, Anthony McMullen 2020 The University of Akron

Supersonic Propulsion: Inlet Shock Wave/Boundary Layer Interaction In A Diffuser, Lucas Fulop, Ian Henry, Jordan Ruffner, Anthony Mcmullen

Williams Honors College, Honors Research Projects

Using a finite-volume approach and ANSYS/FLUENT, supersonic flow over a 2-D ramp of varying angles is modeled. The computational results from this model will be used to further explore the design of supersonic diffusers used on military aircraft. Using grid capturing features and inflation layers, shockwave and boundary layer interactions will be observed as well as wave-associated pressure changes in supersonic turbulent flow. The Spalart-Allmaras single-equation model of turbulent flow will be used in all simulations to more accurately represent the phenomena that occur in such high-speed environments. The size of upstream zones and recirculation zones will be obtained through …


Characterizing Premixed Syngas Combustion In Micro-Channels, Sunita Pokharel 2020 West Virginia University

Characterizing Premixed Syngas Combustion In Micro-Channels, Sunita Pokharel

Graduate Theses, Dissertations, and Problem Reports

Increasing demands in the next-generation portable power-generation devices such as unmanned aerial vehicles (UAV), microsatellite thrusters, micro-chemical reactors and sensors calls for fuels with high specific energy and low emissions to meet the current demand of green energy. Fuel-lean synthesis gas (syngas) meets both these requirements exhibiting a promising route to a clean and green environment. Thus, it is of critical importance to characterize syngas combustion and understand its properties in the micro-combustion industry. In addition to complicated flame dynamics in microscale systems, varying the syngas-fuel mixture composition as well as the boundary conditions and geometry of a combustor significantly …


Double Wall Cooling Of An Effusion Plate With Simultaneous Cross Flow And Impingement Jet Array Internal Cooling, Phil Ligrani, Austin Click, David Ritchie, Federico Liberatore, Rajeshriben Patel, Yin-Hsiang Ho 2019 University of Alabama in Huntsville

Double Wall Cooling Of An Effusion Plate With Simultaneous Cross Flow And Impingement Jet Array Internal Cooling, Phil Ligrani, Austin Click, David Ritchie, Federico Liberatore, Rajeshriben Patel, Yin-Hsiang Ho

PRC-Affiliated Research

The present study considers comparisons of hot-side effusion plate results for a mainstream flow passage with CR = 1 and for a mainstream flow passage with CR = 4. The coolant supply arrangement for both CR contraction ratio values includes simultaneous use of cross flow and an impingement jet array. For the effusion cooled/hot surface, presented are spatially-resolved distributions of surface adiabatic film cooling effectiveness, and surface heat transfer coefficients (measured using infrared thermography). These results are given for main flow Reynolds numbers Rems of 89,900 to 95,800. For this main flow Reynolds number range, four different combination values of …


Double Wall Cooling Of An Effusion Plate With Simultaneous Cross Flow And Impingement Jet Array Internal Cooling, Phil Ligrani, Austin Click, David Ritchie, Federico Liberatore, Rajeshriben Patel, Yin-Hsiang Ho 2019 University of Alabama in Huntsville

Double Wall Cooling Of An Effusion Plate With Simultaneous Cross Flow And Impingement Jet Array Internal Cooling, Phil Ligrani, Austin Click, David Ritchie, Federico Liberatore, Rajeshriben Patel, Yin-Hsiang Ho

PRC-Affiliated Research

The present study considers comparisons of hot-side effusion plate results for a mainstream flow passage with CR = 1 and for a mainstream flow passage with CR = 4. The coolant supply arrangement for both CR contraction ratio values includes simultaneous use of cross flow and an impingement jet array. For the effusion cooled/hot surface, presented are spatially-resolved distributions of surface adiabatic film cooling effectiveness, and surface heat transfer coefficients (measured using infrared thermography). These results are given for main flow Reynolds numbers Rems of 89,900 to 95,800. For this main flow Reynolds number range, four different combination values of …


Double Wall Cooling Of An Effusion Plate With Simultaneous Cross Flow And Impingement Jet Array Internal Cooling, Phil Ligrani, Austin Click, David Ritchie, Federico Liberatore, Rajeshriben Patel, Yin-Hsiang Ho 2019 University of Alabama in Huntsville

Double Wall Cooling Of An Effusion Plate With Simultaneous Cross Flow And Impingement Jet Array Internal Cooling, Phil Ligrani, Austin Click, David Ritchie, Federico Liberatore, Rajeshriben Patel, Yin-Hsiang Ho

PRC-Affiliated Research

The present study considers comparisons of hot-side effusion plate results for a mainstream flow passage with CR = 1 and for a mainstream flow passage with CR = 4. The coolant supply arrangement for both CR contraction ratio values includes simultaneous use of cross flow and an impingement jet array. For the effusion cooled/hot surface, presented are spatially-resolved distributions of surface adiabatic film cooling effectiveness, and surface heat transfer coefficients (measured using infrared thermography). These results are given for main flow Reynolds numbers Rems of 89,900 to 95,800. For this main flow Reynolds number range, four different combination values of …


Performance Enhancement And Characterization Of An Electromagnetic Railgun, Paul M. Gilles 2019 California Polytechnic State University, San Luis Obispo

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 …


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