Aerospace Engineering Commons^™

Modeling And Preliminary Finite Element Analysis On The Spun Structure For The Cpintersep Project, Jason Carpenter, Kelly Cheng, Jeffrey Ma, Richard Pelham, Kevin Povey

Aerospace Engineering

This paper details the process of modeling and importing the model into FEA for the spun structure of the BS376 spacecraft. Engineering drawings were converted into 3D models using Pro/Engineer and then imported and into Patran for pre-processing of a Finite Element Model. To verify the Finite Element Model, several test cases were set up and solved using Nastran solver. Our simple load cases were found to be in congruence with analytical solution methods validating the finite element model.

Aerodynamics Of A Supersonic Projectile In Proximity To A Solid Surface, Graham Doig, Tracie Barber, Eddie Leonardi, Andrew J. Neely, Harald Kleine

Aerospace Engineering

Flow around a Mach 2.4 NATO 5.56 mm projectile in close proximity to a ground plane was investigated using computational fluid dynamics for a direct numerical reproduction of live-range experiments. The numerical approach was validated against both the live-range tests and subsequent wind-tunnel experiments. A nonspinning half-model and a full, spinning projectile were examined to clarify the influence of rotation. Multiple ground clearances were tested to obtain clear trends in changes to the aerodynamic coefficients, and the three-dimensional propagation and reflection of the shock waves were considered in detail. The behavior of the flow in the near wake was also …

The Effectiveness Of Damage Arrestment Devices In Delaying Fastener-Hole Interaction Failures In Carbon Fiber Polyurethane Foam Composite Sandwich Panels Subjected To Static And Dynamic Loading Under Increased Temperatures, Dominic E. Surano

Master's Theses

A study was conducted to investigate simple, cost-effective manufacturing techniques to delay skin-core delamination, micro-buckling and bearing stress failures resulting from fastener-hole interactions. Composite sandwich panels, with and without damage arrestment devices (DADs), were subjected to monotonic compression at a rate of 5mm per second, and compression-compression fatigue at 50% yield at an amplitude of 65%, under temperatures of 75, 100, 125, 150, 175, and 200 °F.

The sandwiches tested were composed of two-layer cross-weave carbon fiber facesheets, a polyurethane foam core, and an epoxy film adhesive to join the two materials. The most successful method to delay the aforementioned …

Development Of Cubesat Vibration Testing Capabilities For The Naval Postgraduate School And Cal Poly San Luis Obispo, Marissa Brummitt

Master's Theses

The Naval Postgraduate School is currently developing their first CubeSat, the Solar Cell Array Tester CubeSat, or NPS-SCAT. Launching a CubeSat, such as NPS-SCAT, requires environmental testing to ensure not only the success of the mission, but also the safety of other CubeSats housed in the same deployer. This thesis will address the development of CubeSat vibration testing methodology at NPS, including subsystem testing, engineering unit qualification, and flight unit testing. In addition, the new Cal Poly CubeSat Test POD Mk III will be introduced and evaluated based upon comparison with the Poly Picosatellite Orbital Deployer (P-POD). Using examples from …

Modeling Of A Gyro-Stabilized Helicopter Camera System Using Neural Networks, Nicholas Joseph Layshot

Master's Theses

On-board gimbal systems for camera stabilization in helicopters are typically based on linear models. Such models, however, are inaccurate due to system nonlinearities and complexities. As an alternative approach, artificial neural networks can provide a more accurate model of the gimbal system based on their non-linear mapping and generalization capabilities.

This thesis investigates the applications of artificial neural networks to model the inertial characteristics (on the azimuth axis) of the inner gimbal in a gyro-stabilized multi-gimbal system. The neural network is trained with time-domain data obtained from gyro rate sensors of an actual camera system. The network performance is evaluated …

An Investigation Of Initially Delaminated Composite Sandwich With Delamination Arrest Mechanism Under Buckling Loading, Tony D. Tran

Master's Theses

This thesis involves the development of a fiberglass-foam composite sandwich structure with the introduction of delamination arrestment keys; therefore, a study of an initially delaminated composite sandwich structure was the experimental analysis on multiple configurations in how the arrestment keys are placed.

The first part of this thesis research was to the experimental design and manufacturing of the composite sandwich plates. These plates were later cut down to the specific test dimensions and manufacturing processes for the composite sandwich plates and test specimens were created. The composite sandwich plates were manufactured using a vacuum resin infusion process. The dimensions of …

The Next Generation Cubesat: A Modular And Adaptable Cubesat Frame Design, James Dolengewicz, Lucas Whipple, Stephanie Wong

Mechanical Engineering

The goal of this project is to develop an improved next-generation CubeSat structure for Cal Poly’s PolySat program. Notable achievements include significantly increased ease of access, design to optimize payload space, improved machinability, increased modularity and a platform which allows for easy integration of future payloads.

Thermal Models For A 3 Cm Miniature Xenon Ion Thruster, Coleman Thomas Younger

Master's Theses

In order to support UCLA’s development of the 3 cm Miniature Xenon Ion (MiXI) thruster, Cal Poly has a 3 cm thruster under development. This version, called MiXI Cal Poly Version 1 (MiXI-CPv1), is complete and has been utilized in vacuum chamber thermal validation testing. Testing on this version was used to check the validity of heat transfer simulations modeled in SolidWorks. Investigations of the 3 cm ion thruster configuration were intended to discover the driving factors affecting the thermal behavior of the discharge chamber and surrounding design space.

Numerical simulations indicate that the heating of the samarium cobalt permanent …

Modeling And Simulation Of Autonomous Thermal Soaring With Horizon Simulation Framework, Zhenhua Li

Master's Theses

A thermal is a column of warm rising air triggered by differential heating on the ground. In recent studies UAVs were programmed to exploit this free atmospheric energy from thermals to improve their range and endurance. Researchers had successfully flown UAVs autonomously with thermal soaring method. Most research involved some form of flight simulation. Improvements to the aircraft and thermal models for simulation purpose would enable researchers to better design their UAVs and explore any potential flaws in their designs. An aircraft simulation with a thermal environment was created in Horizon Simulation Framework, a modeling and verification framework that was …

Hot Air Balloon Navigation, Dustin Blackwell

Aerospace Engineering

This report describes a program used for navigating a hot air balloon.  The program, Balloon_Trip, was written using MATLAB and gives a flight path to follow from a start position to an end position.  Balloon_Trip calculates the flight path by taking in wind conditions and then flying through these different winds so as to steer the hot air balloon.  The program calculates the flight path by taking into consideration at all times how the wind will propel the balloon while it is rising or falling in elevation.  It then takes the most direct and least complicated, if not fastest, …

Static And Fatigue Failure Response Of Woven Carbon Fiber Specimens With Double Edge Notches, Ahmad J. Amini

Master's Theses

Carbon fiber composites are continually seeing increased use in aerospace applications. It is necessary to understand their failure modes in order to properly design and perform analysis on structures constructed primarily from them. This thesis studies woven carbon fiber composites with and without double-edge notches in a series of static and fatigue tests performed on an Instron 8801 servo-hydraulic testing system.

Specimens were constructed of Advanced Composites Group product # LTM45EL woven carbon fiber pre-preg/epoxy and were cut to approximately 9-inch in length and 1-inch in width. Notches were cut into some of the specimens using a slitting saw blade …

Design And Wind Tunnel Testing Of Cal Poly's Amelia 10 Foot Span Hybrid Wing-Body Low Noise Cestol Aircraft, Kristina K. Jameson, David D. Marshall, Robert Ehrmann, Eric Paciano, Rory Golden, Dave Mason

Aerospace Engineering

California Polytechnic Corporation, Georgia Tech Research Institute (GTRI), and DHC Engineering collaborated on a NASA NRA to develop and validate predictive capabilities for the design and performance of Cruise Efficient, Short TakeOff and Landing (CESTOL) subsonic aircraft. In addition, a large scale wind tunnel effort to validate predictive capabilities for aerodynamic performance and noise during takeoff and landing has been undertaken.

The model, Advanced Model for Extreme Lift and Improved Aeroacoustics (AMELIA), was designed as a 100 passenger, N+2 generation, regional, CESTOL airliner with hybrid blended wingbody with circulation control. The model design was focused on fuelsavings and noise goals …

Mission Performance As Point Performance, Robert A. Mcdonald

Aerospace Engineering

The cruise or loiter performance of an aircraft is intimately tied to its wing loading (W/S) and its thrust to weight ratio (T/W). Paradoxically, mission performance is often not considered when these fundamental aircraft parameters are determined in conceptual design. In this research, the traditional constraint diagram is extended to include contours of range parameter. This point performance metric represents the mission performance capability of the aircraft without sizing the aircraft to a particular mission. This gives the designer an immediate and intuitive understanding of the tradeoff between the point and mission performance of the aircraft. This improved constraint diagram …

Parameter Estimation Of Fundamental Technical Aircraft Information Applied To Aircraft Performance, Michael Vallone

Master's Theses

Inverse problems can be applied to aircraft in many areas. One of the disciplines within the aerospace industry with the most openly published data is in the area of aircraft performance. Many aircraft manufacturers publish performance claims, flight manuals and Standard Aircraft Characteristics (SAC) charts without any mention of the more fundamental technical information of the drag and engine data. With accurate tools, generalized aircraft models and a few curve-fitting techniques, it is possible to evaluate vehicle performance and estimate the drag, thrust and fuel consumption (TSFC) with some accuracy. This thesis is intended to research the use of aircraft …

An Investigation Of Damage Arrestment Devices Application With Fastener/Hole Interaction, Richard Vincent S. Balatbat

Master's Theses

This thesis presents a parametric study on the effects of how damage arrestment devices application interacts with a fastener in a composite sandwich panel. The primary objective of the damage arrestment device was to prevent the failure of the composite face sheet, such as crack propagation, around the hole/fastener joint. The damage arrestment devices are made of composite strips that are inserted under the face sheet to increase the overall structural strength of the panel and to prevent the propagation of failure along the hole. This was supposed to be a quicker and stronger alternative to potted inserts for composite …

Development Of A Small And Inexpensive Terrain Avoidance System For An Unmanned Aerial Vehicle Via Potential Function Guidance Algorithm, Shane Alan Wallace

Master's Theses

Despite the first unmanned aerial vehicle (UAV) mission being flown on Aug 22 1849 to bomb Venice UAVs have only recently began to modernize into sophisticated tools beyond simple aerial vehicles. With an increasing number of potential applications, such as cargo delivery, communications, search and rescue, law enforcement, and homeland security, the need for appropriate UAV technology advancement also arose. Here, the development of a low-cost collision avoidance system is described. Hardware was tested and selected based on predetermined constraints and goals. Additionally, a variety of potential functions were explored and assessed at their effectiveness in preventing a collision of …

Development Of Measurement Methods For Application To A Wind Tunnel Test Of An Advanced Transport Model, Robert S. Ehrmann

Master's Theses

California Polytechnic State University, San Luis Obispo is currently working towards developing a Computational Fluid Dynamics (CFD) database for future code validation efforts. Cal Poly will complete a wind tunnel test on the Advanced Model for Extreme Lift and Improved Aeroacoustics (AMELIA) in the National Full-Scale Aerodynamics Complex (NFAC) 40 foot by 80 foot wind tunnel at NASA Ames Research Center in the summer of 2011. The development of two measurement techniques is discussed in this work, both with the objective of making measurements on AMELIA for CFD validation.

First, the work on the application of the Fringe-Imaging Skin Friction …

Picasso Interface For Horizon Simulation Framework, Brian E. Kirkpatrick

Master's Theses

The Horizon Simulation Framework, or HSF, is a modeling and simulation framework compiled from C/C++ source code into a command line program. Picasso is an interface designed to control the input files to Horizon by providing visual tools to create and manipulate the XML files used to define an HSF system of assets, their environment, and other simulation parameters. Picasso also supports the visualization of Horizon output in several different forms, and import mechanics from online space object catalogues.

Implementation Of A Conrad Probe On A Boundary Layer Measurement System, Charles Rocky Ulk

Master's Theses

This thesis presents the design, calibration, and performance evaluation of a type of two-hole pressure probe anemometer known as a Conrad probe, as well as its subsequent implementation on an autonomous, compact boundary layer measurement device and its first application for subsonic in-flight measurements of a swept wing boundary layer. Calibration of the Conrad probe was accomplished using two calibration functions and a non-nulling method for resolving in-plane flow velocity direction and magnitude over a range of ±30 degrees. This approach to calibration and application offered the advantages of rapid data acquisition with lower energy consumption than alternative methods for …

Matlab Structural Analysis Code For String Wing Box Structure, Sean Brown

Aerospace Engineering

This report outlines the method used for analysis of a wing box structure for the experimental “stringy” wing structure often used in light RC aircraft. This code is able to find the displacement of each joint, and the stress and forces in each member of the truss structure. It also has the features of load and structure visualization, Kevlar string removal, user-defined point and distributed loading functions, and user-defined failure criteria function. This method and resulting code is meant for use in the support of the Human Powered Helicopter project being undertaken by the Aerospace and Mechanical Engineering Department at …

Analysis Of A Passive Flow Control Device Via Flow Visualization Techniques, Cheryl R. Graham, Shi (Peter) Huang

Aerospace Engineering

This report details an experiment done to verify the effectiveness of a passive flow control system on a two-dimensional bluff body, blunt trailing edge model in controlling wake dimension and Karman vortex sheds. An earlier experiment by Park, et.al.[1] performed analysis via wind tunnel pressure testing and computerized model to determine the ideal proportions of such a tab design and identify the flow properties responsible for the potential drag reduction. To obtain visual verification of the existence of these concepts, a bluff body model proportionally identical to the one used by Park, et.al., was designed and tested in a water …

Interplanetary Gravity Assisted Trajectory Optimizer (Igato), Jason Bryan

Aerospace Engineering

Interplanetary space travel is an extremely complicated endeavor that is severely limited by our current technological advancements. The amount of energy required to transport a spacecraft from one planet to the next, or even further, is extraordinary and in some cases is even impossible given our current propulsive capabilities. Due to these complications, the search for other means of exchanging energy became imperative to future space exploration missions. One particularly powerful method that was discovered, and the most commonly used one, is referred to as planetary gravity assist. In order to plan out multiple gravity assist trajectories, complex and robust …

Autonomous Control Of The Cal Poly Motion Flight Simulator, Andrew M. Anderson

Aerospace Engineering

An autonomous controller for the Cal Poly Motion Flight Simulator was developed such that the simulated Van’s RV-7 flies a standard light aircraft traffic pattern without any human pilot input. First, an autopilot was developed in Simulink to control the aircraft’s altitude, airspeed, and heading independent of each other. The performance of the autopilot has been tested to perform with a response sufficient for precise navigation. A C++ s- function was written as a mission controller that followed a pre-programmed path around a known airport. The aircraft performs a standard left 45 degree entry into the traffic pattern, lands on …

Analysis Of F-104c World's Altitude Record Flight, William J. Day

Aerospace Engineering

No abstract provided.

Design, Fabrication, And Testing Of An Automotive Turbocharger-Based Gas Turbine Engine, John Kyle Thoma, Daniel Shehan, Benjamin Naravage, Jacob Melvin

Aerospace Engineering

A fully-functioning, self-sustaining gas turbine engine was designed and built. The engine was constructed around a Holset HE351 VGT automobile turbocharger, containing compressor and turbine assemblies on a common shaft. Other components of the engine were either purchased or designed and fabricated in-house. During initial testing of the completed engine, the turbocharger, however, was found to have extensive damage to the internal oil seals, and so the project could not be completed as planned. Instead, the combustor design and fabrication was completed for stand-alone testing. The combustion chamber was designed so that the flame tube could be easily changed out …

Alterations Of The Cal Poly Supersonic Wind Tunnel To Increase Accuracy And Prove The Absence Of Shockwaves, Garrett A. Lovell, Hector A. Gonzalez

Aerospace Engineering

The calibration and improvement of the Cal Poly supersonic wind tunnel was performed in order to create a fully functional facility for supersonic testing. While investigating possible shocks present in the wind tunnel, it was discovered that the real concern was not the tunnel but the measurement systems. Both measurement systems, pitot tube and Schlieren, were evaluated and were found to be deficient. The pitot system had so much play in it that it bent backward every time the tunnel was run invalidating the results, and giving false shock data. The Schlieren system was missing one vital component to make …

Cal Poly Flight Test Platform For Instrument Development, Kyle Schaller, Ian Muceus, Aaron Ells

Aerospace Engineering

This report summarizes a six month effort to conceptually design, develop, and build an unmanned aerial vehicle to test a boundary layer data system (BLDS) developed by Dr. Russell Westphal and his team of mechanical engineering senior design students. The project is funded by Edwards Air Force Base and the United States Air Force Research Laboratory. During the first Cal Poly quarter of project work, January 4, 2010 to March 18, 2010, the team completed a conceptual and preliminary design. During the second quarter, March 18, 2010 to June 12, 2010, the team completed the construction and initial flight test …

Improved Computational And Experimental Validation Using Different Turbulence Models, Jay Marcos, David D. Marshall

Aerospace Engineering

This paper will explore the methods and techniques necessary to perform a more accurate CFD validation of experimental results. The methods and techniques used will be validated against experimental wind tunnel data of a 2D high lift airfoil with a 3D engine performed by Georgia Tech Research Institute. Preliminary results showed that computational methods over predict the lift and drag coefficient, while still showing very similar trends in CL and CD. To further improve the preliminary results and the predictive capabilities, different turbulence models will be investigated. Results of this validation will assist in determining the appropriate turbulence models, boundary …

Analysis Of Curvature Effects On Boundary Layer Separation And Turbulence Model Accuracy For Circulation Control Applications, Daniel Wilde

Aerospace Engineering

This set of analyses involves flow separation in high curvature regions with special attention to circulation control implementations. Blown flaps of various shapes designed by Rory Golden for use on the AMELIA, or Advanced Model for Extreme Lift and Improved Aeroacoustics, short takeoff vehicle have exhibited flow separation at locations where flap curvature changes. Investigating this problem, its causes, and potential solutions, I have concluded that the separation is equally a function of the flow simulation turbulence model used, and the geometry of the flap itself. Using Gambit version 11.0.1 for grid generation and Fluent version 6.3.26 for CFD calculations, …

Hybrid Rocket Motor, Zach Arena, Alexander Athougies, Alden Rodulfo

Aerospace Engineering

This project involves the re-design, manufacturing, and testing of the Cal Poly Space System’s 4th iteration of an M-class 98mm hybrid rocket motor. This motor utilizes hydroxyl-terminated polybutadiene as fuel with liquid nitrous oxide as the oxidizer. Modeling and analysis was conducted on a 12 port self-impinging swirl injector and fuel manufacturing to improve performance. Several hot and cold flow tests were conducted to validate the analysis and predict performance values. Test results included two test fires resulting in an average of 212 lbf of thrust for 6 seconds with an Isp of 160 seconds and an average thrust of …