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Measurement System Characterization In The Presence Of Measurement Errors, Sean A. Como 2012 Old Dominion University

Measurement System Characterization In The Presence Of Measurement Errors, Sean A. Como

Mechanical & Aerospace Engineering Theses & Dissertations

In the calibration of a measurement system, data are collected in order to estimate a mathematical model between one or more factors of interest and a response. Ordinary least squares is a method employed to estimate the regression coefficients in the model. The method assumes that the factors are known without error; yet, it is implicitly known that the factors contain some uncertainty. In the literature, this uncertainty is known as measurement error. The measurement error affects both the estimates of the model coefficients and the prediction, or residual, errors. There are some methods, such as orthogonal least squares, that …


Transient Turbine Engine Modeling With Hardware-In-The-Loop Power Extraction, Michael W. Corbett, Peter T. Lamm, Philip R. Owen, S. Danny Phillips, Mark J. Blackwelder, J. Timothy Alt, John M. McNichols, Michael A. Boyd, Mitch Wolff 2012 U.S. Air Force Research Laboratory

Transient Turbine Engine Modeling With Hardware-In-The-Loop Power Extraction, Michael W. Corbett, Peter T. Lamm, Philip R. Owen, S. Danny Phillips, Mark J. Blackwelder, J. Timothy Alt, John M. Mcnichols, Michael A. Boyd, Mitch Wolff

Mechanical and Materials Engineering Faculty Publications

Increasingly high aircraft power demands require that the interactions between an aircraft’s electrical subsystem and the engine subsystem be considered in dynamic, systemlevel tests. Traditionally, system-level dynamics have only been captured in completely assembled aircraft systems. Component-level or subsystem-level optimization is no longer appropriate because highly interdependent dynamics between subsystems only become apparent during system-level analysis. In an effort to reduce the high cost of testing integrated power and propulsion systems in an altitude-simulating wind tunnel, alternatives such as modeling and simulation are considered. Synchronizing and coupling simulations of vastly different time scales is possible, but the resulting system simulation …


Unsteady Specific Work And Isentropic Efficiency Of A Radial Turbine Driven By Pulsed Detonations, Kurt P. Rouser 2012 Air Force Institute of Technology

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 2012 California Polytechnic State University, San Luis Obispo

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 2012 California Polytechnic State University, San Luis Obispo

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 …


Low Cost Vacuum Chamber Design For Electromagnetic Railgun Operation, Andrew W. Bothwell, David J. Foster 2012 California Polytechnic State University, San Luis Obispo

Low Cost Vacuum Chamber Design For Electromagnetic Railgun Operation, Andrew W. Bothwell, David J. Foster

Aerospace Engineering

This report describes the design and fabrication of a low cost vacuum chamber capable of supporting the operation of an electromagnetic railgun. This would be used to simulate the impact of high velocity impacts in space. The vacuum chamber was constructed out of 10in diameter 10ft PVC pipe with a Wye fitting for viewing impacts during testing. The chamber was designed to accommodate a 6.5in X 6.5in X 60in railgun. The vacuum chamber feedthroughs were designed to be able to carry 1-2Mamps at 8kV to the railgun. The vacuum chamber is capable of reaching 50 Torr and remaining under 100 …


Interstellar Mission To Gliese 581, Brock Schmalzel, Brian Tsoi 2012 California Polytechnic State University, San Luis Obispo

Interstellar Mission To Gliese 581, Brock Schmalzel, Brian Tsoi

Aerospace Engineering

This report details a conceptual design for a one-way, interstellar mission, based upon assumed technological advances over the next few hundred years. It addresses the unique challenges associated with an interstellar mission, looking at both developed and theoretical technologies. This report looks specifically at propulsion systems required to reach an exoplanet. In addition, the power, communication, and orbital trajectories are analyzed to see the differences and technological advancements necessary for future missions and the proposed interstellar mission. The destination for the interstellar mission in Gliese 581, a star system located 20.3 light years away and has 5 known planets and …


Accelerating Lambert's Problem On The Gpu In Matlab, Nathan Parrish 2012 California Polytechnic State University, San Luis Obispo

Accelerating Lambert's Problem On The Gpu In Matlab, Nathan Parrish

Aerospace Engineering

The challenges and benefits of using the GPU to compute solutions to Lambert’s Problem are discussed. Three algorithms (Universal Variables, Gooding’s algorithm, and Izzo’s algorithm) were adapted for GPU computation directly within MATLAB. The robustness of each algorithm was considered, along with the speed at which it could be computed on each of three computers. All algorithms used were found to be completely robust. Computation time was measured for computation within a for-loop, a parfor-loop, and a call to the MATLAB command ‘arrayfun’ with gpuArray-type inputs. Then, a Universal Variables Lambert’s solver was written in CUDA and compiled for use …


Test And Verification Of Vortex Shedding For A 3d Bluff Body, Paul D. Innes, Charles E. Carlson 2012 California Polytechnic State University, San Luis Obispo

Test And Verification Of Vortex Shedding For A 3d Bluff Body, Paul D. Innes, Charles E. Carlson

Aerospace Engineering

Testing of a 3D bluff body with and without end plate tabs was performed in the California Polytechnic State University 3x4 ft low speed wind tunnel. The CP values were obtained for the test case with no end plate tabs for speeds of 10, 15, 20, and 30 m/s. It was observed that stronger vortex shedding ocured at the higher speed test cases. The model was shimmed to be at approximately 5° angle of attack in order to obtain symmetrical negative CP spikes for the top and bottom of the model without tabs. Trends were observed and compared …


Instrument Panel Design, Martin Bialy, Amber Carney, Michael Roche 2012 California Polytechnic State University, San Luis Obispo

Instrument Panel Design, Martin Bialy, Amber Carney, Michael Roche

Aerospace Engineering

This project focused on the design and implementation of an Electronic Flight Instrument System for a home built experimental aircraft known as a CH-701. Older aircraft use manual gauges and dials based on varying internal instruments such as gyro’s and the like but many of these traditional instruments to a singular GUI displaying multiple instruments data at one time. These devices are aimed at helping the pilot stay more alert and aware when flying between automatic warnings when in dangerous flying conditions / configurations as well as simplifying the instrument panel to only display what is absolutely necessary. These programs …


Global Launch Vehicle Selector, Keisuke Suzuki 2012 California Polytechnic State University, San Luis Obispo

Global Launch Vehicle Selector, Keisuke Suzuki

Aerospace Engineering

No abstract provided.


The Numerical Open-Source Many-Body Simulator (Noms), Jason Lloyd Daniel, Javen Kyle Foster-O'Neal 2012 California Polytechnic State University, San Luis Obispo

The Numerical Open-Source Many-Body Simulator (Noms), Jason Lloyd Daniel, Javen Kyle Foster-O'Neal

Aerospace Engineering

This paper outlines the setup and creation of an object-oriented N-body simulator as part of a continued project to explore physical phenomenon and human-computer natural interaction technologies. The tools and processes required to build an N-body simulator are also included. Several integrators were evaluated based on their ability to maintain system energy The 2nd order integrator Verlet and 3rd order integrator Hermite algorithms had the greatest accuracy to model large-scale N-body dynamics for their given computation time. Other algorithms required significantly shorter time steps to achieve similar short-term accuracy. At present, NOMS can reasonably simulate 10,000 particles at less than …


Comprehensive Matlab Gui For Determining Barycentric Orbital Trajectories, Steve Katzman 2012 California Polytechnic State University, San Luis Obispo

Comprehensive Matlab Gui For Determining Barycentric Orbital Trajectories, Steve Katzman

Aerospace Engineering

When a 3-body gravitational system is modeled using a rotating coordinate frame, interesting applications become apparent. This frame, otherwise known as a barycentric coordinate system, rotates about the system’s center of mass. Five unique points known as Lagrange points rotate with the system and have numerous applications for spacecraft operations. The goal of the Matlab GUI was to allow easy manipulation of trajectories in a barycentric coordinate system to achieve one of two end goals: a free-return trajectory or a Lagrange point rendezvous. Through graphical user input and an iterative solver, the GUI is capable of calculating and optimizing both …


Effect Of Multifunctional Material On The Mechanical Behavior Of Composite Structure Using Finite Element Analysis, Nicholas A. Romonoski 2012 California Polytechnic State University, San Luis Obispo

Effect Of Multifunctional Material On The Mechanical Behavior Of Composite Structure Using Finite Element Analysis, Nicholas A. Romonoski

Aerospace Engineering

No abstract provided.


Development Of A Pyrotechnic Shock Simulation Apparatus For Spacecraft Applications, Joseph Binder, Matthew McCarty, Chris Rasmussen 2012 California Polytechnic State University, San Luis Obispo

Development Of A Pyrotechnic Shock Simulation Apparatus For Spacecraft Applications, Joseph Binder, Matthew Mccarty, Chris Rasmussen

Aerospace Engineering

This report details the research, design, construction, and testing of a pyrotechnic shock simulation apparatus for spacecraft applications. The apparatus was developed to be used in the Space Environments Lab at California Polytechnic State University. It will be used for testing spacecraft components with dimensions up to 24”x12”x12” as well as CubeSats. Additionally, it may be used as an instructional or demonstrational tool in the Aerospace Department’s space environments course. The apparatus functions by way of mechanical impact of an approximately 20 lb stainless steel swinging hammer. Tests were performed to verify the simulator’s functionality. Suggestions for improvement and further …


Thermal Vacuum Integration For Cal Poly's Space Environments Laboratory, Chelsea Barackman, Steven Jackowski 2012 California Polytechnic State University, San Luis Obispo

Thermal Vacuum Integration For Cal Poly's Space Environments Laboratory, Chelsea Barackman, Steven Jackowski

Aerospace Engineering

The purpose of the senior project is to construct a thermal vacuum by utilizing a preexisting vacuum chamber in the Space Environments Lab, and a donated Advanced Thermal Sciences (ATS) chiller. While a thermal vacuum is already available on campus, building one for the Space Environments Lab would grant undergraduates access to the equipment, allowing a much better understanding of testing methods and procedures in use by the aerospace industry. This paper explains the design and analysis of the thermal vacuum (T-VAC) project as well as the operation and procedures required for the ATS chiller and fill/drain tank. The thermal …


Multi-Dimensional Modeling Of Charring Ablators, Haoyue Weng, Huaibao Zhang, Ovais U. Khan, Alexandre Martin 2012 University of Kentucky

Multi-Dimensional Modeling Of Charring Ablators, Haoyue Weng, Huaibao Zhang, Ovais U. Khan, Alexandre Martin

Mechanical Engineering Faculty Publications

Re-entry of a spacecraft occurs at the hypersonic regime where the flow field is extremely complex: high temperature gradients occurring in the shock-layer region ionize and dissociate the air. Even if a large portion of heat generated during this process is convected away in the surrounding air, a fraction of it is still transferred to the vehicle. Therefore, it is important to protect the vehicle with a suitable kind of shielding. Of the many techniques available today, use of ablative material is gaining popularity. The basic idea behind an ablating heat shield is that the energy incident on the spacecraft …


The Synergistic Integration Of Computational Fluid Dynamics And Experimental Fluid Dynamics For Ground Effect Aerodynamics Studies, TJ Barber, G Doig, C Beves, I Watson, S Diasinos 2012 University of New South Wales

The Synergistic Integration Of Computational Fluid Dynamics And Experimental Fluid Dynamics For Ground Effect Aerodynamics Studies, Tj Barber, G Doig, C Beves, I Watson, S Diasinos

Aerospace Engineering

This article highlights the ‘synergistic’ use of experimental fluid dynamics (EFD) and computational fluid dynamics (CFD), where the two sets of simulations are performed concurrently and by the same researcher. In particular, examples from the area of ground effect aerodynamics are discussed, where the major facility used was also designed through a combination of CFD and EFD. Three examples are than outlined, to demonstrate the insight that can be obtained from the integration of CFD and EFD studies. The case studies are the study of dimple flow (to enhance aerodynamic performance), the analysis of a Formula-style front wing and wheel, …


Aerodynamics Of An Aerofoil In Transonic Ground Effect: Methods For Blowdown Wind Tunnel Scale Testing, G. Doig, T. J. Barber, A. J. Neely, D. D. Myre 2012 University of New South Wales

Aerodynamics Of An Aerofoil In Transonic Ground Effect: Methods For Blowdown Wind Tunnel Scale Testing, G. Doig, T. J. Barber, A. J. Neely, D. D. Myre

Aerospace Engineering

No abstract provided.


Development Of A Flight Test Program For A Homebuilt Zenith Stol Ch 701, Reed Danis, Dave Nguyen 2012 California Polytechnic State University, San Luis Obispo

Development Of A Flight Test Program For A Homebuilt Zenith Stol Ch 701, Reed Danis, Dave Nguyen

Aerospace Engineering

The objective of this senior project is to prepare a phase I flight test program for a homebuilt Zenith CH 701 kit aircraft. The CH 701 is a small, short takeoff and landing experimental aircraft. A team including several Cal Poly students helped to construct the airframe and avionics of a 701 during the 2011-2012 academic year. The flight test program is necessary for obtaining unrestricted FAA flight certification for the completed aircraft. A set of test flight cards were created to aid in meeting the 25 to 40 hours of required phase I flight testing. These cards include specific …


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