Investigations Of A Surrogate Fuel Based On Fischer-Tropsch Gtl And Ctl In Cvcc, Idi And Di Compression Ignition Engines,
2023
Georgia Southern University
Investigations Of A Surrogate Fuel Based On Fischer-Tropsch Gtl And Ctl In Cvcc, Idi And Di Compression Ignition Engines, Amanda C. Weaver
College of Graduate Studies: Theses & Dissertations
With the increase in availability, feedstocks, and properties of alternative fuels, compatibility issues emerge between current engine platforms often requiring a limit on the blend percentage of alternative fuel in conventional fuel or alteration to the engine platform. Two key metrics were identified, autoignition quality and lubrication characteristics, as vital for the proper function of a compression ignition engine, and if the blend of alternative fuels matches these two criteria for the diesel standard, then the resulting blend percentage can be considered as a viable alternative for complete replacement of conventional petroleum ULSD. Autoignition quality was matched using blends S-8, …
Noise And Propulsive Efficiency Interactions For Rotors And Propellers At Constant Thrust,
2022
Embry-Riddle Aeronautical University
Noise And Propulsive Efficiency Interactions For Rotors And Propellers At Constant Thrust, Riccardo Roiati
Doctoral Dissertations and Master's Theses
In the emerging market of Advanced Air Mobility (AAM), aerospace companies have been designing and prototyping electric and hybrid vehicles to revolutionize travel. These vehicles must have low noise and particulate emissions while also having enough propulsive efficiency to complete the mission. This thesis aims to study the relationship between noise and propulsive efficiency as related to any aircraft equipped with an electric motor and a variable pitch rotor/propeller. The combination of the electric motor with the variable pitch propeller/rotor allows for a decoupled rotational speed and torque generation, meaning that the electric motor can generate the same amount of …
Quasi 1d Modelling Of A Scramjet Engine Cycle Using Heiser-Pratt Approach,
2022
Mississippi State University
Quasi 1d Modelling Of A Scramjet Engine Cycle Using Heiser-Pratt Approach, Asmaa Chakir
Theses and Dissertations
Scramjet engines are key for sustained hypersonic flights. Analytic models play a critical role in the preliminary design of a scramjet engine configuration. The objective of this research is to develop and validate a quasi-1D model for the scramjet engine encompassing inlet, isolator and combustor, to evaluate the impact of flight conditions and design parameters on the engine functionality. The model is developed assuming isentropic flow in the inlet with a single turn; modified Fanno-flow equations in the isolator that account for the area change of the core flow; and the combustor is modeled using Heiser-Pratt equations accounting for the …
The Design And Development Of A Miniature Gridded Ecr Ion Thruster,
2022
Western Michigan University
The Design And Development Of A Miniature Gridded Ecr Ion Thruster, Nicholas Nuzzo
Masters Theses
Plasma propulsion, a specific subset of electric propulsion (EP), is a class of space propulsion that produces plasma by excitation of a propellant at or above its ionization energy. This ionized propellant is then accelerated by an externally applied field (magnetic and/or electric) and produces thrust. There is an increasing need for miniaturization in spacecraft technology and the use of plasma EP devices in space propulsion. These systems provide an advantage over traditional chemical propulsion solutions which are less efficient and have more mass. Miniaturization of EP devices allows missions to have more space and mass available for their payloads …
2022 Summer-Fall Graduate Recognition Program,
2022
The University of Alabama in Huntsville
2022 Summer-Fall Graduate Recognition Program, Propulsion Research Center, Robert Frederick
PRC Graduate Recognition
This program includes the graduate recognition program for summer and fall 2022. Includes photographs, upcoming events, recent publications, and student profiles.
Spacecraft Systems & Navigation,
2022
Embry-Riddle Aeronautical University
Spacecraft Systems & Navigation, Christopher Vanacore
Student Works
This textbook is steered towards higher educational course entailed in Commercial Space Operations. This textbook will be covering in detail Orbital Satellites, and Spacecraft. These topics are discussed according to their application, design, and environment. The power system, shielding and communication systems are reviewed along with their missions, space, environment and limitations. Any vehicle, whether manned or unmanned, intended for space travel is a spacecraft. A spacecraft's required systems and equipment depend on the information it will acquire and the tasks it will perform. Although their levels of sophistication vary widely, they re all subject to the harsh conditions of …
Application Of Direct Feedback Tunable Diode Laser Absorption Spectroscopy Within A Hybrid Rocket Combustor,
2022
Louisiana State University and Agricultural and Mechanical College
Application Of Direct Feedback Tunable Diode Laser Absorption Spectroscopy Within A Hybrid Rocket Combustor, Connor Becnel
LSU Master's Theses
With interest in space travel and space-related science increasing in recent years, significant efforts to reduce the cost and increase the safety of rocket motors have become commonplace. Liquid rockets are currently the most commonly used system, but there is interest in the reduced complexity of hybrid rockets. For these hybrid rocket motors to become the norm, extensive research on their complex boundary layer combustion needs to be performed. Modeling these hybrid systems is of much interest to companies developing rocket motors; ultimately, small-scale experiments will help validate their behavior. This paper covers the application of a near-infrared tunable diode …
Seal For A Wave Rotor Disk Engine,
2022
Air Force Institute of Technology
Seal For A Wave Rotor Disk Engine, Christopher Tait, Pejman Akbari, Brian Sell, Marc D. Polanka
AFIT Patents
A unique seal for a wave rotor disk engine is disclosed herein. The seal is operable for sealing a region between a rotor and a rotor casing. The seal is spring loaded and will engage with the tip of the rotor to reduce pressure loss within the wave rotor disk engine.
Impulse Measurement Methods For Pulsed Laser Ablation Propulsion,
2022
Rose-Hulman Institute of Technology
Impulse Measurement Methods For Pulsed Laser Ablation Propulsion, Ishaan Mishra, Scott Kirkpatrick
Rose-Hulman Undergraduate Research Publications
Pulsed laser ablation propulsion has the potential to revolutionize space exploration by eliminating the requirement of a spacecraft to carry its propellant and power source as the high-power laser is situated off-board. More experimentation needs to be done to optimize this propulsion system and understand the mechanisms of thrust generation. There are many methods used to calculate the impulse imparted in pulsed laser ablation experiments. In this paper, key performance parameters are derived for some of the impulse measurement methods used in ablation propulsion experiments. Regimes discussed include the torsional pendulum system, simple pendulum system, and solid and liquid microspheres.
A Comparative Performance Analysis Of The Novel Turboaux Engine With A Turbojet Engine, And A Low-Bypass Ratio Turbofan Engine With An Afterburner,
2022
Old Dominion University
A Comparative Performance Analysis Of The Novel Turboaux Engine With A Turbojet Engine, And A Low-Bypass Ratio Turbofan Engine With An Afterburner, Kaleab Fetahi, Sharanabasaweshwara A. Asundi, Arthur C. Taylor
Mechanical & Aerospace Engineering Faculty Publications
Presented herein is a comparative performance analysis of a novel turbofan engine with an auxiliary combustion chamber, nicknamed the TurboAux engine, against a turbojet engine, and a low bypass ratio turbofan engine with an afterburner is presented. The TurboAux engine is an adaption of the low-bypass ratio turbofan engine, but with secondary combustion in an auxiliary bypass annular combustion chamber for thrust augmentation. The TurboAux engine is envisioned with the desire to facilitate clean secondary burning of fuel at temperatures higher than in the main combustion chamber with air exiting the low-pressure compressor. The comparative study starts by analyzing the …
Feasibility Of Low-Enriched Uranium Fueled Nuclear Thermal Propulsion In The Low-Thrust Region Below 16klbf,
2022
University of Alabama in Huntsville
Feasibility Of Low-Enriched Uranium Fueled Nuclear Thermal Propulsion In The Low-Thrust Region Below 16klbf, Samantha B. Rawlins, Dale L. Thomas
PRC-Affiliated Research
No abstract provided.
Turbine Cooling System With Energy Separation,
2022
Air Force Institute of Technology
Turbine Cooling System With Energy Separation, James L. Rutledge, Matthew Fuqua, Carol M. Bryant
AFIT Patents
A method and system for cooling an engine and/or vehicle using energy separation is disclosed herein. An energy separation device is operable for separating a compressed gaseous coolant stream into a first relatively cooler coolant flow stream and a second relatively hotter coolant flow stream. The relative cooler coolant flow stream is directed to a first region requiring increased cooling and the relative hotter coolant flow stream is directed to a second region requiring lower cooling than the first region in the engine or vehicle.
Disk Engine With Circumferential Swirl Radial Combustor,
2022
Air Force Institute of Technology
Disk Engine With Circumferential Swirl Radial Combustor, Brian Bohan, Marc Polanka, Bennett Staton
AFIT Patents
A disk engine and system configured to provide high power at a reduced axial length is disclosed herein. The disk engine includes a radial compressor, a compressor discharge manifold positioned circumferentially about compressor, a combustion chamber positioned within the discharge manifold and a radial turbine positioned radially inward of the combustion chamber.
Controller Platform Design And Demonstration For An Electric Aircraft Propulsion Driv,
2022
University of Arkansas, Fayetteville
Controller Platform Design And Demonstration For An Electric Aircraft Propulsion Driv, Rosten Sweeting
Graduate Theses and Dissertations
With the growth in the aerospace industry there has been a trend to optimize the performance of an aircraft by reducing fuel consumption and operational cost. Recent advancements in the field of power electronics have pushed towards the concepts of hybrid electric aircraft also known as more electrical aircrafts. In this work, a custom controller board for an electric aircraft propulsion drive was designed to drive a permanent magnet synchronous motor. Design of the controller board required knowledge of the topology selection and power module selections. Simulations of the system were performed using MATLAB/Simulink to analyze the overall performance of …
Performance Study Of Post-Processed Additively Manufactured Low Thrust Nozzles,
2022
Air Force Institute of Technology
Performance Study Of Post-Processed Additively Manufactured Low Thrust Nozzles, Tyler W. Gerhold
Theses and Dissertations
This research explores metal post-processing techniques to effectively reduce the large anomalous protrusions found in small additively manufactured low thrust rocket nozzles. Research has found that nozzles of this kind can experience losses in thrust of over 40%. Analytic theory of adiabatic nozzle flow with viscous losses for additively manufactured nozzles does not align with what has been found when tested experimentally. Compressible flow losses, such as shock wave formation inside the nozzle diverging cone, are likely the leading causes of such loss. Reduction in nozzle irregularities can likely yield results seen in analytic theory with similar performance to traditional …
Method And Simulation Of On-Orbit Sub-Microthrust Evaluation,
2022
California Polytechnic State University, San Luis Obispo
Method And Simulation Of On-Orbit Sub-Microthrust Evaluation, Jonathan Hood
Master's Theses
With the advent of smaller satellites, along with the need for less than 0.1 μN precision attitude control for interferometry and imaging missions, finer micro- to sub-micro- thrusters have become an area of high interest. As thrusters are developed and ground-tested, it is necessary to evaluate their thrust performance on-orbit. On-orbit measurements offer actual thrust performance in mission conditions, free from ground facility vibrations and miniaturization restraints, and allow a thruster system to achieve a NASA Technology Readiness Level (TRL) of 7-8. A review is conducted of existing and proposed ground and on-orbit thrust measurement techniques. Experimental gaps and complementary …
Direct Simulation And Reduced-Order Modeling Of Premixed Flame Response To Acoustic Modulation,
2022
Mississippi State University
Direct Simulation And Reduced-Order Modeling Of Premixed Flame Response To Acoustic Modulation, Zheng Qiao
Theses and Dissertations
This dissertation introduces a general, predictive and cost-efficient reduced-order modeling (ROM) technique for characterization of flame response under acoustic modulation. The model is built upon the kinematic flame model–G-equation to describe the flame topology and dynamics, and the novelties of the ROM lie in i) a procedure to create the compatible base flow that can reproduce the correct flame geometry and ii) the use of a physically-consistent acoustic modulation field for the characterization of flame response. This ROM addresses the significant limitations of the classical kinematic model, which is only applicable to simple flame configurations and relies on ad-hoc models …
Using An Ultrasonic Technique To Determine Burning Rate Law,
2022
University of Alabama in Huntsville
Using An Ultrasonic Technique To Determine Burning Rate Law, Brennan Hatton Haralson
Honors Capstone Projects and Theses
No abstract provided.
2022 Spring Graduate Recognition Program,
2022
The University of Alabama in Huntsville
2022 Spring Graduate Recognition Program, Propulsion Research Center, Robert Frederick
PRC Graduate Recognition
This program includes the graduate recognition program for spring 2022. Includes photographs, upcoming events, recent publications, and student profiles.
Performance Variability In Solid Rocket Motors,
2022
University of Alabama in Huntsville
Performance Variability In Solid Rocket Motors, Manvith Amara
Honors Capstone Projects and Theses
No abstract provided.
