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Full-Text Articles in Engineering

Analysis Of An Electrospray Thruster With A Concave Propellant Meniscus, Adam Nicholas Huller Dec 2023

Analysis Of An Electrospray Thruster With A Concave Propellant Meniscus, Adam Nicholas Huller

Masters Theses

The low thrust, high specific impulse, and low mass of electrospray thrusters (ETs) make them ideal for maneuvering nanosatellites, especially with the new requirement to deorbit a satellite within five years of completing its mission. These innovative thrusters use electrohydrodynamic principles of electrospray (ES) to provide thrust. These principles have been subject to much research over the past decade, though much more research is needed to fully understand the underlying physics of these thrusters. The first part of this study establishes a procedure for analyzing the theoretical thrust performance of an ET, by using propellant properties and well-documented ES scaling …


Investigation Of Interplanetary Trajectories To Sedna, John W. Sarappo Iii, Samuel Brickley, Iliane Domenech, Lorenzo Franceschetti, James E. Lyne May 2023

Investigation Of Interplanetary Trajectories To Sedna, John W. Sarappo Iii, Samuel Brickley, Iliane Domenech, Lorenzo Franceschetti, James E. Lyne

Chancellor’s Honors Program Projects

No abstract provided.


Nuclear Thermal Rocket Engine Control Autonomy Via Embedded Decision, David Sikorski May 2022

Nuclear Thermal Rocket Engine Control Autonomy Via Embedded Decision, David Sikorski

Doctoral Dissertations

This doctoral dissertation presents an investigation of embedded decision capabilities as a means for developing nuclear reactor autonomous control. Nuclear thermal propulsion (NTP) is identified as a high priority technology for development, and is the focus of this research. First, a background investigation is presented on the state of the art in nuclear thermal rocket (NTR) engine control and modeling practices, resulting in the development of a low order NTR engine dynamic model based on the literature. The engine model was used to perform the following investigation, and is intended to serve as a research platform for the future development …


Titan Aerogravity Assist For Saturn Orbital Insertion And Study Of Enceladus, Hannah Hajdik, Samantha Ramsey, Richard Andrew Wright, Nathan Stover, Jason Patel, Jonathan Spitznas, Nishant Lokanathan, James Evans Lyne May 2020

Titan Aerogravity Assist For Saturn Orbital Insertion And Study Of Enceladus, Hannah Hajdik, Samantha Ramsey, Richard Andrew Wright, Nathan Stover, Jason Patel, Jonathan Spitznas, Nishant Lokanathan, James Evans Lyne

Chancellor’s Honors Program Projects

No abstract provided.


System Architecture Design And Development For A Reusable Lunar Lander, Chad Batten, Camille E. Bergin, Aaron Crigger, Darryl Harris, Gillian Suzanne Mcglothin May 2019

System Architecture Design And Development For A Reusable Lunar Lander, Chad Batten, Camille E. Bergin, Aaron Crigger, Darryl Harris, Gillian Suzanne Mcglothin

Chancellor’s Honors Program Projects

No abstract provided.


Depot For Martian And Extraterrestrial Transport Resupply (Demetr), Emily Beckman, Ethan Vogel, Caleb Peck, Nicholas Patterson May 2018

Depot For Martian And Extraterrestrial Transport Resupply (Demetr), Emily Beckman, Ethan Vogel, Caleb Peck, Nicholas Patterson

Chancellor’s Honors Program Projects

No abstract provided.


Enceladus Sample Return Mission, Braxton Brakefield, Rekesh Ali, Andrew Bishop, Shelby Honaker, David Taylor May 2017

Enceladus Sample Return Mission, Braxton Brakefield, Rekesh Ali, Andrew Bishop, Shelby Honaker, David Taylor

Chancellor’s Honors Program Projects

No abstract provided.


Development, Analysis, And Optimization Of A Swirl-Promoting Mean Flow Solution For Solid Rocket Motors, Andrew Steven Fist Dec 2016

Development, Analysis, And Optimization Of A Swirl-Promoting Mean Flow Solution For Solid Rocket Motors, Andrew Steven Fist

Masters Theses

This work demonstrates and analyses a new flow candidate for describing the internal gaseous motion in simulated rocket motors. The fundamental features of this solution include the conservation of key system properties also incorporated in the classic Taylor-Culick (TC) system (i.e. inviscid, axisymmetric, steady and rotational properties), while allowing for the development of a swirling velocity component. The work compares the new solution to the development and formulation of the classic TC system, ultimately identifying that both the new and classic solutions are special cases of the Bragg-Hawthorne equation. Following this development, the text then explores the development of energy-optimized …


Improved Modeling Of Atmospheric Entry For Meteors With Nose Radii Between 5cm And 10m, Jakob Dale Brisby May 2016

Improved Modeling Of Atmospheric Entry For Meteors With Nose Radii Between 5cm And 10m, Jakob Dale Brisby

Masters Theses

Atmospheric entry studies typically look closely at the peak heating rate that a body encounters during its trajectory. This is an extremely important phenomenon to study because it allows engineers to determine if a trajectory is possible with given materials and craft design specifications. It also allows designers to choose what type of method will be used for mitigating the enormous heat fluxes during entry. In general, it is accepted that during the super-sonic flight regime the body will continue to be heated and an ablative heat shield often is used to deal with these heating processes. The theory outlined …


Development Of A Database For Rapid Approximation Of Spacecraft Radiation Dose During Jupiter Flyby, Sarah Gilbert Stewart May 2016

Development Of A Database For Rapid Approximation Of Spacecraft Radiation Dose During Jupiter Flyby, Sarah Gilbert Stewart

Masters Theses

Interplanetary and deep space missions greatly benefit from the utilization of gravitational assists to reach their final destinations. By closely “swinging by” a planet, a spacecraft can gain or lose velocity or change directions without requiring any expenditure of propulsion. In today’s budget-driven design environment, gravity assist flybys reduce the need for on-board fuel and propulsion systems, thereby reducing overall cost, increasing payload and mission capacity, increasing mission life, and decreasing travel time. It is expected that many future missions will also be designed to swing by Jupiter in order to utilize a gravity assist. However, there is a risk …


Control System Requirements For A Nuclear Thermal Propulsion System, Adam Hasse, Michael Smith, Bradley Pershke, Andrew Adams, Stephen GilliAm May 2016

Control System Requirements For A Nuclear Thermal Propulsion System, Adam Hasse, Michael Smith, Bradley Pershke, Andrew Adams, Stephen GilliAm

Chancellor’s Honors Program Projects

No abstract provided.


Trajectory Analysis And Comparison Of A Linear Aerospike Nozzle To A Conventional Bell Nozzle For Ssto Flight, Elizabeth Lara Lash May 2015

Trajectory Analysis And Comparison Of A Linear Aerospike Nozzle To A Conventional Bell Nozzle For Ssto Flight, Elizabeth Lara Lash

Masters Theses

Single-stage to orbit (SSTO) rocket technology offers the potential to substantially reduce launch costs, but has yet to be considered practical for conventional launch vehicles. However, new research in composite propellant tank technology opens the field for renewed evaluation. One technology that increases the efficiency and feasibility of SSTO flight is an altitude compensating rocket engine nozzle, as opposed to a conventional constant area, bell nozzle design. By implementing an altitude compensation nozzle, such as a linear, aerospike nozzle for in-atmosphere flight, the propellant mass fraction (PMF) may be reduced by as much as seven percent compared to a conventional …


Design Of Economical Upper Stage Hybrid Rocket Engine, Christopher R. Potter May 2013

Design Of Economical Upper Stage Hybrid Rocket Engine, Christopher R. Potter

Chancellor’s Honors Program Projects

No abstract provided.


A Survey Of Gaps, Obstacles, And Technical Challenges For Hypersonic Applications, Timothy Andrew Barber May 2012

A Survey Of Gaps, Obstacles, And Technical Challenges For Hypersonic Applications, Timothy Andrew Barber

Masters Theses

The object of this study is to canvas the literature for the purpose of identifying and compiling a list of Gaps, Obstacles, and Technological Challenges in Hypersonic Applications (GOTCHA). The significance of GOTCHA related deficiencies is discussed along with potential solutions, promising approaches, and feasible remedies that may be considered by engineers in pursuit of next generation hypersonic vehicle designs and optimizations. Based on the synthesis of several modern surveys and public reports, a cohesive list is formed, consisting of widely accepted areas needing improvement and falling under several general categories. These include: aerodynamics, propulsion, materials, analytical modeling, CFD modeling, …


Optimization And Design For Heavy Lift Launch Vehicles, Paul Andreas Ritter May 2012

Optimization And Design For Heavy Lift Launch Vehicles, Paul Andreas Ritter

Masters Theses

The simulation and evaluation of an orbital launch vehicle requires consideration of numerous factors. These factors include, but are not limited to the propulsion system, aerodynamic effects, rotation of the earth, oblateness, and gravity. A trajectory simulation that considers these different factors is generated by a code developed for this thesis titled Trajectories for Heavy-lift Evaluation and Optimization (THEO). THEO is a validated trajectory simulation code with the ability to model numerous launch configurations. THEO also has the capability to provide the means for an optimization objective. Optimization of a launch vehicle can be specified in terms of many different …


Particle Shielding For Human Spaceflight: Electrostatic Potential Effects On The Störmer Magnetic Dipole Exclusion Region, Benjamin Alan Klamm Dec 2011

Particle Shielding For Human Spaceflight: Electrostatic Potential Effects On The Störmer Magnetic Dipole Exclusion Region, Benjamin Alan Klamm

Masters Theses

A basic hybrid radiation shield concept, consisting of both a monopole positive electrostatic potential barrier and a current-carrying superconducting solenoid, was predicted to provide a more effective method of shielding a habitable torus region than a solenoid acting alone. A randomized position and velocity vector simulation of equal-energy iron ions using a Lagrangian reference frame was performed on the exact magnetic field integral for the solenoid and a discrete summation electrostatic field for a toroidal monopole array approximating a potential surface. Each particle is injected at a specific energy (100, 150 MeV and 1 GeV). Two cases were evaluated at …


A Feasibility Study For Using Commercial Off The Shelf (Cots) Hardware For Meeting Nasa’S Need For A Commercial Orbital Transportation Services (Cots) To The International Space Station - [Cots]2, Chad Lee Davis Aug 2011

A Feasibility Study For Using Commercial Off The Shelf (Cots) Hardware For Meeting Nasa’S Need For A Commercial Orbital Transportation Services (Cots) To The International Space Station - [Cots]2, Chad Lee Davis

Masters Theses

The space vehicle system concept (i.e. resupply vehicle) described is based on the new direction that President George W. Bush announced on January 14, 2004 for NASA’s Human Exploration, which has the space shuttle retiring in 2011 following the completion of the International Space Station (ISS). This leads to a problem for the ISS community regarding the capability of meeting a sixty metric-ton cargo shortfall in resupply and the ability of returning large payloads, experiment racks and any other items too large to fit into a crew only type spacecraft like the Orion or Soyuz. NASA and the ISS partners …


Vortex Driven Acoustic Flow Instability, Lutz Blaette May 2011

Vortex Driven Acoustic Flow Instability, Lutz Blaette

Doctoral Dissertations

Most combustion machines feature internal flows with very high energy densities. If a small fraction of the total energy contained in the flow is diverted into oscillations, large mechanical or thermal loads on the structure can be the result, which are potentially devastating if not predicted correctly. This is particularly the case for lightweight high performing devices like rockets. The problem is commonly known as "Combustion Instability".
Several mechanisms have been identified in the past that link the flow field to the acoustics inside a combustion chamber and thereby drive or dampen oscillations, one of them being vortex shedding.

The …


Development And Analysis Of Onboard Translunar Injection Targeting Algorithms, Phillippe Lyles Winters Reed May 2011

Development And Analysis Of Onboard Translunar Injection Targeting Algorithms, Phillippe Lyles Winters Reed

Masters Theses

Several targeting algorithms are developed and analyzed for possible future use onboard a spacecraft. Each targeter is designed to determine the appropriate propulsive burn for translunar injection to obtain desired orbital parameters upon arrival at the moon. Primary design objectives are to minimize the computational requirements for each algorithm but also to ensure reasonable accuracy, so that the algorithm’s errors do not force the craft to conduct large mid-course corrections. Several levels of accuracy for dynamical models are explored, the convergence range and speed of each algorithm are compared, and the possible benefits of the Broyden and trust-region targeters are …