Engineering Commons^™

Advanced Visualization Techniques Of Hot-Jet Combustion Of Lean And Ultra-Lean Substances, Timothy I. Machin, Li Qiao

The Summer Undergraduate Research Fellowship (SURF) Symposium

Research has been conducted on ignition of natural gas as a potential replacement for fossil fuels. A reason natural gas is not widely used and adapted is because of the harmful emissions created when combusted in rich mixtures, but if the gas can be burned at a lean or ultra-lean equivalence ratio, these emissions can be reduced or even eliminated. One method of burning lean and ultra-lean substances is by use of hot-jet ignition. This method ignites the substance near its combustion temperature, reducing the harmful emissions. This method is not yet fully understood, and so research must be done …

High-Order Shock Capturing For Computational Aeroacoustics, Samuel Otto, Gregory Blaisdell

The Summer Undergraduate Research Fellowship (SURF) Symposium

Jet noise is not only an annoyance to passengers and communities near airports, it is a major contributor to hearing loss in veterans who served on aircraft carriers, as well as a significant limiting factor for the growth of commercial airlines. High-fidelity large eddy simulation (LES) is an important tool for analyzing and predicting jet noise; however the utilized non-dissipative high order finite difference schemes produce instabilities at shock waves. Schemes for capturing shock waves, however, are more dissipative and do a poor job preserving turbulent structures and acoustic waves. To maximize the strengths of both approaches, hybrid methods utilize …

Interaction Model Of Functions In The National Airspace System, Nathan F. Koerschner, Steven J. Landry

The Summer Undergraduate Research Fellowship (SURF) Symposium

The National Airspace System (NAS) is comprehensively described by five functions derived from big-picture goals: (1) conflict detection and resolution, (2) controlling aircraft states, (3) traffic flow management, (4) controlling passenger states, and (5) controlling company resources. It can be reasonably assumed that these functions interact in some way; this interaction is currently unknown. A model of the entire NAS would be helpful in discovering these interactions, yet no such comprehensive model exists. To address this problem an agent-based state-based model was created in MATLAB. To date, only functions (1) and (2) were implemented. Running the model shows that there …

Validation Of Long-Fiber Thermoplastic Composite Models, Christian A. Vuong, Megan Kinney, Michael Sangid

The Summer Undergraduate Research Fellowship (SURF) Symposium

With increased pressure to reduce energy consumption, long-fiber reinforced thermoplastic composites (LFTs) are of interest to aerospace and automotive industries due to their light weight in combination with other desirable mechanical properties and ease of manufacturing to replace common materials such as aluminum and magnesium. However, the performance of LFTs is highly dependent on microstructural variables such as fiber length and orientation, which are heavily influenced by the manufacturing process. Accurately predicting these factors would allow for more rapid advances in LFTs by reducing the experiments needed for certification and decreasing expenses. While models that serve this purpose exist, the …

The Stability And Control Of The Single Track Vehicles, Shyngys Karimov, Martin Corless

The Summer Undergraduate Research Fellowship (SURF) Symposium

Bicycles, motorcycles and scooters are all examples of the single track vehicles. The dynamics of the single track vehicle involve many degrees of freedom and various modes which govern its performance, making a complicated and interesting research topic. Motorcycle in motion can roll, yaw, and steer about the steering axis. It has three main modes which determine the motion and stability of it, they are weave, capsize, and wobble. The motorcycle performance is limited by the behavior of its modes, and if even one of the modes becomes unstable, the vehicle will roll over, and crash. The goal of this …

Remote Sensing Using Signals Of Opportunity, Alibek Yertay, James L. Garrison

The Summer Undergraduate Research Fellowship (SURF) Symposium

Today, there are more than eight thousand satellites in space. Therefore, Radio Frequency (RF) signals broadcast from satellites can be accessed from almost every point on the earth. There will be number of satellites available at most points on earth with different frequency bands. These satellite signals can be used for remote sensing, therefore software that visualizes footprints of satellites and shows characteristics of every satellite available at any point would be useful in determining which signals are available for reflectometry, method where direct satellite signals and reflected satellite signals are received and compared for analysis of certain area. There …

Testing Of Gelled And Neat Hypergolic Propellants, Bhuvi Swarna Nirudhoddi, Timothee Pourpoint

The Summer Undergraduate Research Fellowship (SURF) Symposium

Hypergolic propellants (hypergols) are propellants that ignite shortly after contact. They omit the requirement of an ignition system, making hypergolic engines simple, reliable and capable of being throttled several times. These advantages make them desirable for deep space missions. However, the applications are severely limited by their toxicity and reactivity. In an effort to increase the safety of manufacturing, shipping, and storing, these propellants can be combined with different gelling agents. The focus of this project is to build an optically accessible combustion chamber pressurized at 200 psi to compare the performance of gelled and neat Monomethyl Hydrazine (MMH) and …

Direct Simulation Monte Carlo Simulation Toolkit For Equilibrium (0d) And Planar Couette Flow (1d), Austin I. Saragih, Alina A. Alexeenko

The Summer Undergraduate Research Fellowship (SURF) Symposium

Visualized simulation tool of Direct Simulation Monte Carlo (DSMC) is essential in aeronautical engineering and gas dynamics, by presenting information that can educate engineers and scientists to preliminarily understand the molecular gas dynamics and direct simulation of gas flows. Two educational tools and models are described for rarified gas flows and simulated particle collisions. A 0-Dimensional DSMC in approach to translational equilibrium was developed to simulate the speed distribution over time and the comparison between the final distribution and the Maxwell-Boltzmann distribution. A 1-Dimensional DSMC for Planar Couette flow was also developed to calculate the number of strikes of the …

Space Systems Engineering Sse 120 - Fall 2013 Space Lecture, Robert J. Twiggs

Robert "Bob" Twiggs STEM Education Collection

Space Systems Engineering SSE 120 - Fall 2013, Space Lecture presented by Professor Bob Twiggs on October 15, 2013.

Space Environment-I Lecture - Powerpoint Presentation, Robert J. Twiggs

Robert "Bob" Twiggs STEM Education Collection

Professor Bob Twiggs PowerPoint lecture on Space Environment presented on October 14, 2013.

Space Systems Engineering Sse 120 - Space Lecture, Fall 2013, Robert J. Twiggs

Robert "Bob" Twiggs STEM Education Collection

Professor Bob Twiggs' preview questions for his space lecture on Space Systems Engineering SSE 120 delivered on October 14, 2013.

High Frequency Combustion Instability Suppression Through The Application Of Varying Bands Of White Noise, John W. Bennewitz

Von Braun Symposium Student Posters

No abstract provided.

Satellite Configuration For Neo Management, Luke Burgess, Grant Bergstue, Spencer Cole, Richard Fork

Von Braun Symposium Student Posters

No abstract provided.

Experimental Investigation Of Orifice-Induced, Cavitation Feedline Instabilities, Matthew A. Hitt

Von Braun Symposium Student Posters

No abstract provided.

Ambient: Affordable Microsatellite Based Internet Access And Environmental Monitoring, Tyler Maddox

Von Braun Symposium Student Posters

No abstract provided.

Defect Detectability Improvement For Conventional Friction Stir Welds, Chris Hill

Von Braun Symposium Student Posters

No abstract provided.

Chargersat-2 Mission Overview, Brittani Searcy, Matt Rodencal

Von Braun Symposium Student Posters

No abstract provided.

Design And Development Of A Microgravity Stowage System Specific For Deep Space Exploration, Taylor Stokes

Von Braun Symposium Student Posters

No abstract provided.

Friction Stir Weld Application And Tooling Design For The Mpcv Stage Adapter, John Alcorn

Von Braun Symposium Student Posters

No abstract provided.

Archaeological Remote Sensing: Exploring The Past From Space, Kel Markert

Von Braun Symposium Student Posters

No abstract provided.

Traditional Boat Building: An Intersection Of Zanzibar’S Culture And Environment, Eric Levenson

Independent Study Project (ISP) Collection

This study examined traditional boat building on Uzi Island as a manifestation of Zanzibar’s relationship of environment and culture. Information was gathered about traditional boat building practices, the resource use and management pertaining to boats, the cultural reliance on boats, and local views on environment and conservation. This information showed that the people of Uzi Island were dependent on the use of traditional boats to maintain their livelihood, however the tree types used for boat building are being over-harvested. This tension of culture and environment exposed the need for conservation of Zanzibar’s natural resources in a manner that does not …

Scalable Autonomous Operations Of Unmanned Assets, Sunghun Jung

Open Access Dissertations

Although there have been great theoretical advances in the region of Unmanned Aerial Vehicle (UAV) autonomy, applications of those theories into real world are still hesitated due to unexpected disturbances. Most of UAVs which are currently used are mainly, strictly speaking, Remotely Piloted Vehicles (RPA) since most works related with the flight control, sensor data analysis, and decision makings are done by human operators. To increase the degree of autonomy, many researches are focused on developing Unmanned Autonomous Aerial Vehicle (UAAV) which can takeoff, fly to the interested area by avoiding unexpected obstacles, perform various missions with decision makings, come …

Kinetic Simulations Of Plasma Plume Potential In A Vacuum Chamber, Joseph J. Wang, Daoru Frank Han, Yuan Hu

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Direct Simulation Monte Carlo and Particle-in-Cell simulations are carried out to study the potential of a mesothermal plasma plume in a vacuum chamber. The results show that the beam potential with respect to the ambient in a vacuum chamber is different from that in space because the facility plasma can prematurely terminate the plume expansion process. As a result, the plume potential measured in a vacuum chamber may be significantly lower than that under the in-space condition. This can lead to under estimation of the backflow of CEX ions and ionized contaminants in plasma thruster plume modeling.

The Comparison Of Composite Aircraft Field Repair Method (Cafrm) With Traditional Aircraft Repair Technologies, Peng Hao Wang

Open Access Dissertations

In the aviation industry, manufacturers made the transition from aluminum to composite materials for the majority of their primary structures over the last few decades. While the design and manufacturing techniques have consistently evolved, field repair methods were consistently overlooked. In this study, specimens fabricated using some of the common repair methods such as the autoclave repair method, and Double Vacuum Debulk (DVD) repair method were tested against the Composite Aircraft Field Repair Method (CAFRM) proposed by the researcher. Specimens were tested with microscopy, acid digestion, short beam shear, and mode I fracture tests. The researcher was able to determine …

Design, Development, And Testing Of A Conformal Power Control Interface For Thrust Vectoring Aircraft, David Rozovski

Open Access Dissertations

Over the last five years, a new power control inceptor for tiltrotor aircraft, known as the Rotational Throttle Interface (RTI) was designed and built. Prior to the RTI, no tiltrotor inceptor had been able to simultaneously indicate both the direction and magnitude of thrust conformally. The purpose of the RTI is to provide an interface that maps to the intended vehicle response throughout ALL ranges of operation. Doing so is expected to reduce confusion that may have contributed to several tiltrotor accidents

Two tests were conducted with the RTI, one at the NASA Vertical Motion Simulator, and one at Canada's …

Spacecraft Orbit Design In The Circular Restricted Three-Body Problem Using Higher-Dimensional Poincaré Maps, Christopher D. Geisel

Open Access Dissertations

Strategies for designing three-dimensional spacecraft trajectories in a multi-body dynamical environment are investigated using four-dimensional Poincaré maps. Unlike the planar circular restricted three-body problem, where a two-dimensional map provides a simplified view of a portion of the vast and often chaotic design space, the spatial problem requires a four-dimensional map to achieve an equivalent perspective. Such higher-dimensional maps present a visualization challenge. Furthermore, a spacecraft in the spatial problem can exhibit fundamentally more diverse and complex behavior than in the planar problem. A novel approach to four-dimensional-map-based design in the spatial circular restricted three-body problem is developed and applied to …

Solution To Certain Problems In The Failure Of Composite Structures, Jonathan Goodsell

Open Access Dissertations

The present work contains the solution of two problems in composite structures. In the first, an approximate elasticity solution for prediction of the displacement, stress and strain fields within the m-layer, symmetric and balanced angle-ply composite laminate of finite-width subjected anticlastic bending deformation is developed. The solution is shown to recover classical laminated plate theory predictions at interior regions of the laminate and thereby illustrates the boundary layer character of this interlaminar phenomenon. The results exhibit the anticipated response in congruence with the solutions for uniform axial extension and uniform temperature change, where divergence of the interlaminar shearing stress is …

Applicability Of Continuum Fracture Mechanics In Atomistic Systems, Shao-Huan Cheng

Open Access Dissertations

By quantitating the amplitude of the unbounded stress, the continuum fracture mechanics defines the stress intensity factor K to characterize the stress and displacement fields in the vicinity of the crack tip, thereby developing the relation between the stress singularity and surface energy (energy release rate G). This G-K relation, assigning physical meaning to the stress intensity factor, makes these two fracture parameters widely used in predicting the onset of crack propagation. However, due to the discrete nature of the atomistic structures without stress singularity, there might be discrepancy between the failure prediction and the reality of nanostructured materials. Defining …

Attitude Estimation For A Gravity Gradient Momentum Biased Nanosatellite, Arash Mehrparvar

Master's Theses

Attitude determination and estimation algorithms are developed and implemented in simulation for the Exocube satellite currently under development by PolySat at Cal Poly. A mission requirement of ±5˚ of attitude knowledge has been flowed down from the NASA Goddard developed payload, and this requirement is to be met with a basic sensor suite and the appropriate algorithms. The algorithms selected in this work are TRIAD and an Extended Kalman Filter, both of which are placed in a simulation structure along with models for orbit propagation, spacecraft kinematics and dynamics, and sensor and reference vector models. Errors inherent from sensors, orbit …

Examination Of Micromotion-Induced Transient Effects Of Brain Tissue Interfaced With A Neural Probe, Michael A. Polanco

Mechanical & Aerospace Engineering Theses & Dissertations

Neural probes are utilized to obtain information regarding the activity of brain cells for neural stimulation. The functional longevity of a probe is dependent upon its ability to minimize injury risk during insertion and the recording period in vivo, which could be related to micromotion-related strain between the probe and surrounding tissue. A series of finite element analyses were conducted using the nonlinear transient dynamic code LSDYNA (LSTC, Livermore, CA) to study the strain induced within the brain in an area around a neural probe. A variety of displacement pulses were input into the brain, first where a high magnitude, …