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Unsteady Total Pressure Measurement For Laminar-To-Turbulent Transition Detection, Akane Sharon Karasawa 2011 California Polytechnic State University, San Luis Obispo

Unsteady Total Pressure Measurement For Laminar-To-Turbulent Transition Detection, Akane Sharon Karasawa

Master's Theses

This thesis presents the use of an unsteady total pressure measurement to detect laminar-to-turbulent transition. A miniature dynamic pressure transducer, Kulite model XCS-062-5D, was utilized to measure the total pressure fluctuations, and was integrated with an autonomous boundary layer measurement device that can withstand flight test conditions. Various sensor-probe configurations of the Kulite pressure transducer were first examined in a wind tunnel with a 0.610 m (2.0 ft) square test section with a maximum operational velocity of 49.2 m/s (110 mph), corresponding dynamic pressure of 1.44 kPa (30 psf). The Kulite sensor was placed on an elliptical nose flat plate …


Thermal Expansions In Wurtzite Aln, Gan, And Inn: First-Principle Phonon Calculations, L.-C. Xu, R.-Z. Wang, Xiaodong Yang, H. Yan 2011 Missouri University of Science and Technology

Thermal Expansions In Wurtzite Aln, Gan, And Inn: First-Principle Phonon Calculations, L.-C. Xu, R.-Z. Wang, Xiaodong Yang, H. Yan

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Using the first-principle phonon calculations under the quasiharmonic approximation, thermal expansions in III-nitrides with wurtzite AlN, GaN, and InN are reported. The results showed that it is different for each thermal expansion of three III-nitrides at low temperatures, which is consistent with their Grneisen parameters as the function of temperature. Below 50 K, negative thermal expansions occur in InN, while GaN and AlN follow the rule of positive thermal expansion. To seek the origin of positivenegative thermal expansion distinction, the mode Grneisen parameters and the phonon spectra are investigated. They indicate that different low-frequency phonon vibration modes correspond to the …


The Future Of Aerospace Propulsion: Visco-Elastic Non-Newtonian Liquids, Nicole Arockiam 2011 Purdue University

The Future Of Aerospace Propulsion: Visco-Elastic Non-Newtonian Liquids, Nicole Arockiam

The Journal of Purdue Undergraduate Research

Aerospace propulsion often involves the spray and combustion of liquids. When a liquid is sprayed, large drops form first, in a process known as primary atomization. Then, each drop breaks up into smaller droplets, in a process known as secondary atomization. This determines final drop sizes, which affect the liquid’s evaporation and mixing rates and ultimately influence combustor efficiency. Little has been published concerning the secondary atomization of visco-elastic non-Newtonian liquids, such as gels. These substances have special potential as aerospace propellants, because they are safer to handle than their Newtonian liquid counterparts, such as water. Additionally, they can be …


Comparison Of Best Economy And Best Power Mixture Settings In The Purdue University Training Fleet, Charles G. Chrisman 2011 Purdue University

Comparison Of Best Economy And Best Power Mixture Settings In The Purdue University Training Fleet, Charles G. Chrisman

Purdue Polytechnic Directed Projects

Purdue University operates a fleet of Cirrus SR20s as training aircraft. Standard operating procedures for the cruise portion of cross country training flights call for 65% power with a best power mixture, also called rich of peak, as opposed to a best economy setting, also called lean of peak. Previous work demonstrated that fuel consumption rates, cylinder head temperatures, and true airspeeds are lower when best economy is employed compared to best power for the same power output. This study confirmed that best economy is associated with a lower fuel consumption rate and lower cylinder head temperatures but was unable …


Comparison Of Turbine Engine Test Cell Airborne Nanoparticle Count Versus Ambient Background Particle Count, Ryne LaRowe 2011 Purdue University

Comparison Of Turbine Engine Test Cell Airborne Nanoparticle Count Versus Ambient Background Particle Count, Ryne Larowe

Purdue Polytechnic Directed Projects

With the establishment of the National Test Facility for Aerospace Fuels and Propulsion at Purdue University in October of 2009, new equipment has been acquired to measure and classify exhaust emissions. This facility utilizes the Honeywell F109 turbofan and Pratt & Whitney PT-6 turboprop engine test cells to analyze the emissions and engine operation of new alternative aviation fuels. This observational study investigates what, if any difference there is in the amount of ambient residual Particulate Matter (PM) in the turbofan engine test cell when compared to ambient particle count associated with the Purdue University Airport (KLAF) property. The project …


Blair Balden, Margaret von Steinen 2011 Western Michigan University

Blair Balden, Margaret Von Steinen

International Faculty Researchers

A visiting professorship at the University of Passau in Passau, Germany for Dr. Blair Balden, a WMU associate professor of aviation, provided an excellent opportunity to share ideas and information about teaching aviation law with professors from Germany and Austria.


Comparison Of A High Purity Germanium Gamma Ray Spectrometer And A Multidimensional Nai(T1) Scintillation Gamma Ray Spectrometer, Greg Stratton 2011 California Polytechnic State University, San Luis Obispo

Comparison Of A High Purity Germanium Gamma Ray Spectrometer And A Multidimensional Nai(T1) Scintillation Gamma Ray Spectrometer, Greg Stratton

Aerospace Engineering

This report compares two different gamma ray spectrometers in terms of performance, operation, and apparatus and also investigates the design and integration challenges of using gamma ray spectrometers in space. The first spectrometer is a one-dimensional high purity germanium (HPGe) spectrometer and the second is a multidimensional NaI(Tl) scintillation spectrometer (MGRS). The key results show that the HPGe exhibits 15 to 27 times better energy resolution than the MGRS, but the MGRS is 52 times more sensitive and removes 177 % more of the background radiation.


3d Cfd On An Open Wheel Race Car Front Wing In Ground Effects, Thomas A. Price 2011 California Polytechnic State University, San Luis Obispo

3d Cfd On An Open Wheel Race Car Front Wing In Ground Effects, Thomas A. Price

Aerospace Engineering

The purpose of the report is to investigate the ability of the Fluent 6.3 k-ε Realizable turbulence model with standard wall functions to model the flow around the front wing of Cal Poly’s 2008 Formula SAE car. The three primary areas of interest are ground effects, the wing wheel interaction, and the wing tip vortices. Fluent was successful at modeling the increase suction from the ground effects, and the upwash due to the wing tip vortices. The results also displayed how the high pressure region in front of the tire propagates forward and interacts with the pressure distribution around the …


A Study On Facility Planning Using Discrete Event Simulation: Case Study Of A Grain Delivery Terminal, Sarah M. Asio 2011 University of Nebraska-Lincoln

A Study On Facility Planning Using Discrete Event Simulation: Case Study Of A Grain Delivery Terminal, Sarah M. Asio

Department of Industrial and Management Systems Engineering: Dissertations, Theses, and Student Research

The application of traditional approaches to the design of efficient facilities can be tedious and time consuming when uncertainty and a number of constraints exist. Queuing models and mathematical programming techniques are not able to capture the complex interaction between resources, the environment and space constraints for dynamic stochastic processes. In the following study discrete event simulation is applied to the facility planning process for a grain delivery terminal. The discrete event simulation approach has been applied to studies such as capacity planning and facility layout for a gasoline station and evaluating the resource requirements for a manufacturing facility. To …


Modeling And Control For Heave Dynamics Of A Flexible Wing Micro Aerial Vehicle Distributed Parameter System, Lisa M. Kuhn 2011 Louisiana Tech University

Modeling And Control For Heave Dynamics Of A Flexible Wing Micro Aerial Vehicle Distributed Parameter System, Lisa M. Kuhn

Doctoral Dissertations

In recent years, much research has been motivated by the idea of biologically-inspired flight. It is a conjecture of the United States Air Force that incorporating characteristics of biological flight into air vehicles will significantly improve the maneuverability and performance of modern aircraft. Although there are studies which involve the aerodynamics, structural dynamics, modeling, and control of flexible wing micro aerial vehicles (MAVs), issues of control and vehicular modeling as a whole are largely unexplored. Modeling with such dynamics lends itself to systems of partial differential equations (PDEs) with nonlinearities, and limited control theory is available for such systems.

In …


Astro Camp Presentation, Get Away Special Team 2011 2011 Utah State University

Astro Camp Presentation, Get Away Special Team 2011

Education and Outreach

No abstract provided.


Aerospike Rockets For Increased Space Launch Capability, Carl R. Hartsfield, Richard D. Branam, Joshua N. Hall, Joseph R. Simmons III 2011 Air Force Institute of Technology

Aerospike Rockets For Increased Space Launch Capability, Carl R. Hartsfield, Richard D. Branam, Joshua N. Hall, Joseph R. Simmons Iii

Faculty Publications

No abstract provided.


Precision Position, Navigation, And Timing Without The Global Positioning System, Kenneth A. Fisher, John F. Raquet 2011 Air Force Institute of Technology

Precision Position, Navigation, And Timing Without The Global Positioning System, Kenneth A. Fisher, John F. Raquet

Faculty Publications

The NAVSTAR Global Positioning System GPS has revolutionized modern warfare. Since 2005 almost all US precision-guided munitions have used GPS targeting data. Consequently, weapons delivery systems are able to strike enemy targets with precision, often resulting in little or no collateral damage. Furthermore, nearly all military assets, including aircraft, tanks, ships, missiles, mortar rounds, cargo boxes, and dismounted Soldiers rely on the accurate position determination that GPS provides. For military users of this system, two main limitations emerge. First, the system relies on line of sight that is, the satellites must be in view of the receiver s antenna so …


X-Hale: Designing The Atmospheric Surveillance Platforms Of The Future, Christopher M. Shearer 2011 Air Force Institute of Technology

X-Hale: Designing The Atmospheric Surveillance Platforms Of The Future, Christopher M. Shearer

Faculty Publications

Imagine the benefits that battlefield commanders or intelligence analysts could derive from an airborne surveillance platform that would carry a 500-pound payload, operate above the range of small arms fire, remain on station for weeks or even years, cost much less than a satellite, and relocate around the globe to a new region of interest within a couple of weeks. Realizing this concept, known as a high-altitude, long-endurance HALE aircraft, is a 10-to-15-year goal of researchers at the Air Force Institute of Technology AFIT. In order to reach this goal, those researchers are following a developmental path similar to the …


Analysis And Design Of A Propulsion System Trade Study Tool For A Boeing 376 Series Communications Satellite, Kevin Dunk 2011 California Polytechnic State University, San Luis Obispo

Analysis And Design Of A Propulsion System Trade Study Tool For A Boeing 376 Series Communications Satellite, Kevin Dunk

Aerospace Engineering

No abstract provided.


The Tracking Performance Of Distributed Recoverable Flight Control Systems Subject To High Intensity Radiated Fields, Rui Wang 2011 Old Dominion University

The Tracking Performance Of Distributed Recoverable Flight Control Systems Subject To High Intensity Radiated Fields, Rui Wang

Electrical & Computer Engineering Theses & Dissertations

It is known that high intensity radiated fields (HIRF) can produce upsets in digital electronics, and thereby degrade the performance of digital flight control systems. Such upsets, either from natural or man-made sources, can change data values on digital buses and memory and affect CPU instruction execution. HIRF environments are also known to trigger common-mode faults, affecting nearly-simultaneously multiple fault containment regions, and hence reducing the benefits of n-modular redundancy and other fault-tolerant computing techniques. Thus, it is important to develop models which describe the integration of the embedded digital system, where the control law is implemented, as well …


A Taskable Space Vehicle: Realizing Cost Savings By Combining Orbital And Suborbital Flight, Thomas Co, Jonathan T. Black 2011 Air Force Institute of Technology

A Taskable Space Vehicle: Realizing Cost Savings By Combining Orbital And Suborbital Flight, Thomas Co, Jonathan T. Black

Faculty Publications

The use of space gives the United States distinct advantages in any battlefield environment, but the high cost of space operations increasingly jeopardizes those advantages. Although the United States pioneered much of the current space technology, declining budgets for space research, development, and operations leave our legacy systems vulnerable to adversaries around the world. Other nations formerly incapable of space exploitation are quickly learning to counter US space technologies at surprisingly low costs. In order to reduce the expense of deploying and maintaining a robust space capability, the Department of Defense (DOD) must change the status quo in space operations …


A Wind Tunnel Technique For The Identification Of Ship Airwake/Rotor Downwash Coupling, Stargel R. Doane 2011 Old Dominion University

A Wind Tunnel Technique For The Identification Of Ship Airwake/Rotor Downwash Coupling, Stargel R. Doane

Mechanical & Aerospace Engineering Theses & Dissertations

A wind tunnel study is performed to analyze the interaction between ship airwakes and helicopter rotor downwash. This interaction is of interest to naval aviators and researchers as this phenomenon is thought to limit helicopter flight envelopes and increase the overall difficulty of maritime rotorcraft operations. In this study, a 1/50th scale simplified naval frigate model and appropriately scaled rotor model are used for all experimental work. A rotor thrust survey was conducted in the immediate vicinity of the landing deck. Two dimensional and stereo particle image velocimetry surveys and rotor thrust measurements with various rotor and ship configurations were …


Interface Circuit For A Multiple-Beam Tuning-Fork Gyroscope With High Quality Factors, Ren Wang 2011 Old Dominion University

Interface Circuit For A Multiple-Beam Tuning-Fork Gyroscope With High Quality Factors, Ren Wang

Mechanical & Aerospace Engineering Theses & Dissertations

This research work presents the design, theoretical analysis, fabrication, interface electronics, and experimental results of a Silicon-On-Insulator (SOI) based Multiple-Beam Tuning-Fork Gyroscope (MB-TFG). Based on a numerical model of Thermo-Elastic Damping (TED), a Multiple-Beam Tuning-Fork Structure (MB-TFS) is designed with high Quality factors (Qs) in its two operation modes. A comprehensive theoretical analysis of the MB-TFG design is conducted to relate the design parameters to its operation parameters and further performance parameters. In conjunction with a mask that defines the device through trenches to alleviate severe fabrication effect on anchor loss, a simple one-mask fabrication process is employed to implement …


A Methodology To Repair Or Deorbit Leo Satellite Constellations, Goksel Gurgenburan 2011 Old Dominion University

A Methodology To Repair Or Deorbit Leo Satellite Constellations, Goksel Gurgenburan

Mechanical & Aerospace Engineering Theses & Dissertations

In this thesis, mitigation of space debris is addressed by examining an approach for repair or de-orbit of a specific population of non-functional Low Earth Orbit (LEO) satellites. Basic orbital mechanics propagation of the orbits was used as the process for computing a solution to the time and intercept position for the targeted satellites. Optimal orbital maneuvers to reach the target satellites from a pre-established orbit were also considered. In this way minimum ΔV budget, rendezvous time and mass budgets were managed. The Clohessy-Wiltshire Equations and two-impulsive rendezvous maneuvers were used to determine the orbital path of a chase satellite …


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