Propulsion and Power Commons^™

Analysis Of Magnetic Nozzle Design For Pulsed Fusion Propulsion System, Richard Hatcher, Milos Stanic, Jason T. Cassibry, J Loverich, M Kundrapu

Von Braun Symposium Student Posters

No abstract provided.

Development Of Tungsten Based Ceramic-Metallic Nuclear Fuel Containing Uranium Oxide For Nuclear Cryogenic Propulsion Stage Project, Jaewon Choi

Von Braun Symposium Student Posters

No abstract provided.

Fusion-Fission Hybrid Pulsed Propulsion System For Improved Space Transportation, Micah Laughmiller

Von Braun Symposium Student Posters

No abstract provided.

Inertial Electrostatic Confinement Diffusion Thruster, Mark Becnel

Von Braun Symposium Student Posters

No abstract provided.

Materials Selection Considerations For Z-Pinch Pulse-Powered Fusion Systems For Space Propulsion, Mitchell Rodriguez

Von Braun Symposium Student Posters

No abstract provided.

Strain Rate And Orientation Dependencies Of The Strength Of Single Crystalline Copper Under Compression, Virginie Dupont, Timothy C. Germann

Aerospace Engineering - Daytona Beach

Molecular dynamics (MD) simulations are used to model the compression under uniaxial strain of copper single crystals of different orientations at various temperatures and strain rates. Uniaxial strain is used because of the close resemblance of the resulting stress state with the one behind a shock front, while allowing a control of parameters such as strain rate and temperature to better understand the behavior under complex dynamic shock conditions. Our simulations show that for most orientations, the yield strength of the sample is increased with increasing strain rate. This yield strength is also dependent on the orientation of the sample, …

Scaling Study Of Wave Rotor Turbo-Normalization Of A Small Internal Combustion Engine, Brandon D. Smith

Theses and Dissertations

One issue facing small Remotely Piloted Aircraft engines is their ability to maintain performance at altitude. Since many of these aircraft use commercial off the shelf engines originally designed for radio controlled aircraft and lawn care implements, the reduced pressure environment significantly degrades the operability of the engine as the altitude increases. An option to overcome this difficulty is to supercharge the system; however most superchargers are designed for larger, typically automotive, engines. As a supercharger's size is decreased, there are large efficiency losses. Therefore, there is a need to accomplish this function on a smaller scale without. One option …

Jet Engine Thrust Ratings, Nihad E. Daidzic

Aviation Department Publications

No abstract provided.

Parametric Instability Investigation And Stability Based Design For Transmission Systems Containing Face-Gear Drives, Meng Peng

Doctoral Dissertations

The objective of this dissertation is to provide a novel design methodology for face-gear transmissions based on system stability - a dynamics viewpoint. The structural dynamics models of transverse and torsional vibrations are developed for face-gear drives with spur pinions to investigate the parametric instability behavior in great depth. The unique face-gear meshing kinematics and the fluctuation of mesh stiffness due to a nonunity contact-ratio are considered in these models. Since the system is periodically timevarying, Floquet theory is utilized to solve the Mathieu-Hill system equations and determine the system stability numerically. To avoid complex numerical computations, Treglod’s approximation is …

On Compressible Gaseous Motions In Swirl Dominated Combustors, Brian A. Maicke

Doctoral Dissertations

In this dissertation, a number of models are derived to describe swirling flows. Both generalized compressible Bragg-Hawthorne and vorticity-stream function frameworks are determined and left in a generic form suitable for describing a number of different scenarios. These systems are solved for the bidirectional vortex flowfield by means of a Rayleigh-Janzen perturbation, which expands the governing equations in terms of the Mach number squared. The resulting equations are solved to provide a semi-analytical solution after the evaluation of a handful of numerical integrals. These solutions further the understanding of compressible flow in swirl-combustors, as previous compressible studies are primarily experimental …

An Experimental Investigation Of A Goldschmied Propulsor, Joshua Roepke

Master's Theses

A wind tunnel investigation of an axisymmetric bluff body, known as a Goldschmied propulsor, was completed. This model conceptually combines boundary layer control and boundary layer ingestion into a single complementary system that is intended to use energy to reduce the axial force on the body by eliminating separation and increasing the pressure recovery aft of the body’s maximum thickness. The goal of the current project was to design, fabricate, and fully document the performance of a wind tunnel model incorporating the Goldschmied propulsor concept and complete an examination of its aerodynamic performance. The investigation took place at California Polytechnic …

Unsteady Specific Work And Isentropic Efficiency Of A Radial Turbine Driven By Pulsed Detonations, Kurt P. Rouser

Theses and Dissertations

There has been longstanding government and industry interest in pressure-gain combustion for use in Brayton cycle based engines. Theoretically, pressure-gain combustion allows heat addition with reduced entropy loss. The pulsed detonation combustor (PDC) is a device that can provide such pressure-gain combustion and possibly replace typical steady deflagration combustors. The PDC is inherently unsteady, however, and comparisons with conventional steady deflagration combustors must be based upon time-integrated performance variables. In this study, the radial turbine of a Garrett automotive turbocharger was coupled directly to and driven, full admission, by a PDC in experiments fueled by hydrogen or ethylene. Data included …

Electric Aircraft Propulsion System, Austin J. Doupe

Aerospace Engineering

This report specifies the purpose, assembly, operation, and data collection of a testing apparatus to characterize small electric aircraft propulsion systems designed for commercial use. This apparatus was constructed with the goal of determining overall system characteristics and efficiencies. The apparatus was pushed to a safety limit as deemed by advisor John Dunning and the results of the experiment were an output power of 3.2kW (25% of max rated power) and a system efficiency of 58.6%, both of which occurred at 2200 RPM. Currently the apparatus needs improvement. It should have an upgraded structure to mount to (instead of the …

High-Fidelity Low-Thrust Trajectory Determination Research And Analysis, Tyler Hill

Aerospace Engineering

This document discusses a numerical analysis method for low thrust trajectory propagation known as the proximity quotient or Q-Law. The process uses a Lyapunov feedback control law developed by Petropoulos^[1] to propagate trajectories of spacecraft by minimizing the user defined function at the target orbit. A simplified propagator is created from the core mechanics of this method in MATLAB and tested in several user defined cases to demonstrate its capabilities. Several anomalies arose in test cases where variations in eccentricity, inclination, right ascension of the ascending node, and argument of perigee were specified. Solutions to these anomalies are discussed …

Preliminary Design Of A Laboratory Cylindrical Hall-Effect Thruster, Scott Mcgrail, Sam Parker

Aerospace Engineering

A 3-cm cylindrical Hall thruster with permanent magnets was designed and modeled. The goal was to design a Hall thruster for Cal Poly’s propulsion laboratory of similar size and performance as Cal Poly’s MiXI thruster. The design process began with an investigation into the physics of Hall thrusters and selection of certain thruster parameters. The selected parameters were the diameter and depth of the channel, the total power input to the system, the discharge supply voltage, the cathode voltage, and the propellant flow rates to the anode and cathode. These parameters were used to determine the operational characteristics of the …

Ramjet Fuel System, Kelsey Selin

Aerospace Engineering

No abstract provided.

De-Orbiting Upper Stage Rocket Bodies Using A Deployable High Altitude Drag Sail, Robert A. Hawkins Jr., Joseph A. Palomares

Aerospace Engineering

This report examines the effectiveness of a drag sail to de-orbit upper stage rocket bodies. Many other perturbations contribute to the de-orbiting of these rocket bodies, and these perturbations will also be discussed briefly. This paper will show the length of time needed to force the altitudes of various launch vehicle stages with varying drag area sizes to less than 100 km. The upper stage of the Delta IV launch vehicle in an orbit with an altitude of 500 km will naturally de-orbit in 720 days but when equipped with a 20 m² drag sail, it will de-orbit in …

Implementation Of A ¼ Inch Hollow Cathode Into A Miniature Xenon Ion Thruster (Mixi), David Wayne Knapp

Master's Theses

Over the last decade, miniature ion thruster development has remained an active area of research do to its low power, low thrust, and high efficiency, however, due to several technical issues; a flight level miniature ion thruster has proved elusive. This thesis covers the design, fabrication, assembly, and test of an altered version of the Miniature Xenon Ion thruster (MiXI), originally developed by lead engineer Dr. Richard Wirz, at the California Institute of Technology (Caltech). In collaboration with Dr. Wirz, MiXI-CP-V3 was developed at Cal Poly San Luis Obispo with the goal of implementing of a ¼ inch hollow cathode …

Hapss, Hybrid Aircraft Propulsion System Synthesis, Michael W. Green

Master's Theses

Hybrid Aircraft Propulsion System Synthesis (HAPSS) is a computer program that sizes and analyzes pure-series hybrid electric propulsion systems for aircraft. The development of this program began during a NASA SBIR contract, in conjunction with Empirical Systems Aerospace (ESAero), with the creation of a propulsion fan design tool. Since the completion of this contract in July 2010, the HAPSS program has been expanded to combine the many aspects of a hybrid propulsion system such as the propulsive fans, electric motors, generators, and controllers, and the internal combustion engines.

This thesis describes the benefits and drawbacks of aircraft hybrid propulsion systems …

Humanitarian Response Unmanned Aircraft System (Hr-Uas), Justin T. Knott, David P. Brundage, John S. Campbell, D. Austin Eldridge, Shaun B. Hooker, Jake R. Mashburn, Jacob L. Philpott

Chancellor’s Honors Program Projects

No abstract provided.