Experimental Investigation Of Suction Slot Geometry On A Goldschmied Propulsor,
2012
California Polytechnic State University, San Luis Obispo
Experimental Investigation Of Suction Slot Geometry On A Goldschmied Propulsor, Nicole M. Thomason
Master's Theses
The Goldschmied Propulsor concept combines boundary layer suction and boundary layer ingestion to improve propulsive efficiency and reduce drag on an axisymmetric body. This investigation of a Goldschmied Propulsor aimed to determine influential characteristics of the suction slot geometry to aid in better slot geometry design and to decrease the suction flow requirements for maintaining attached flow over the entire model surface. The Propulsor model was 38.5 inches in length with a max diameter of 13.5 inches. Three suction slot geometries were investigated with the addition of aluminum cusps to the slot entrance. The cusps varied in the distance they …
Design And Analysis Of A Reusable N2o-Cooled Aerospike Nozzle For Labscale Hybrid Rocket Motor Testing,
2012
California Polytechnic State University, San Luis Obispo
Design And Analysis Of A Reusable N2o-Cooled Aerospike Nozzle For Labscale Hybrid Rocket Motor Testing, Daniel Joseph Grieb
Master's Theses
A reusable oxidizer-cooled annular aerospike nozzle was designed for testing on a labscale PMMA-N20[1] hybrid rocket motor at Cal Poly-SLO.[2] The detailed design was based on the results of previous research involving cold-flow testing of annular aerospike nozzles and hot-flow testing of oxidizer-cooled converging-diverging nozzles. In the design, nitrous oxide is routed to the aerospike through a tube that runs up the middle of the combustion chamber. The solid fuel is arranged in an annular configuration, with a solid cylinder of fuel in the center of the combustion chamber and a hollow cylinder of fuel lining …
Dynamic Model Creation And Scripting Support In The Horizon Simulation Framework,
2012
California Polytechnic State University, San Luis Obispo
Dynamic Model Creation And Scripting Support In The Horizon Simulation Framework, Brian Jeffrey Butler
Master's Theses
Dynamic model creation and support for the Lua scripting language was added to the Horizon Simulation Framework used for the verification and validation of system-level requirements. The addition of scripting support allows for subsystem models and their algorithms to be defined using a simpler scripting language, rather than C++. The Luabind library by Rasterbind software is used to expose the C++ algorithms and classes to Lua that are already defined in the framework. Interoperability between Lua and C++ code allows for the ease of use of a scripting language while utilizing the utility classes and functions already created. The dynamic …
Study Of Turbulence-Radiation Interaction In Hypersonic Turbulent Boundary Layers,
2012
Missouri Unviersity of Science and Technology
Study Of Turbulence-Radiation Interaction In Hypersonic Turbulent Boundary Layers, L. (Lian) Duan, M. P. Martín, A. M. Feldick, M. F. Modest, D. A. Levin
Mechanical and Aerospace Engineering Faculty Research & Creative Works
Direct numerical simulations are conducted to investigate the effect of turbulence-radiation interaction in hypersonic turbulent boundary layers, representative of the Orion crew exploration vehicle at the peak heating condition during reentry. Both the effects of emission and absorption are considered by solving the radiative transfer equation using the tangent slab approximation and a spectral model with line-by-line accuracy. Nondimensional governing parameters to measure the significance of turbulence-radiation interaction are proposed, and the direct numerical simulation fields with and without radiation coupling are used to assess turbulence-radiation interaction. Is it found that the fluid medium within the boundary layer is optically …
The Effect Of Elevated Temperature On The Inelastic Deformation Behavior Of Pmr-15 Solid Polymer,
2012
Air Force Institute of Technology
The Effect Of Elevated Temperature On The Inelastic Deformation Behavior Of Pmr-15 Solid Polymer, Chad E. C. Ryther
Theses and Dissertations
The inelastic deformation behavior of PMR-15 neat resin, a high-temperature thermoset polymer, was investigated at temperatures in the 274-316°C range. The experimental program was developed to explore the influence of temperature on tensile loading, relaxation and creep behaviors of PMR-15. The results demonstrate that the mechanical behavior of PMR-15 exhibits a strong dependence on temperature. During strain-controlled tensile loading, the slope of the stress-strain curve in the quasi-elastic region decreases and the flow stress level decreases with increasing temperature. During relaxation, the amount of the stress drop decreases with increasing temperature. Based on experimental results the Viscoplasticity Based on Overstress …
Aircraft Operations Based Mission Requirements,
2012
California Polytechnic State University - San Luis Obispo
Aircraft Operations Based Mission Requirements, Robert A. Mcdonald
Aerospace Engineering
The mission capabilities of aircraft in the current commercial fleet are a combined result of many factors. The launch customer for each aircraft has a voice in determining the requirements. The manufacturer desires to best position the aircraft in the market considering their own aircraft and their competitors aircraft it will replace and compete with. Consequently, anyone considering the development of an aircraft to compete with or replace an aircraft in-service must do more than simply choose to meet the capabilities of that aircraft. This is especially true when unconventional systems are considered; the fundamental trade-offs for these systems may …
High Performance Modeling Of Atmospheric Re-Entry Vehicles,
2012
University of Kentucky
High Performance Modeling Of Atmospheric Re-Entry Vehicles, Alexandre Martin, Leonardo C. Scalabrin, Iain D. Boyd
Mechanical Engineering Faculty Publications
Re-entry vehicles designed for space exploration are usually equipped with thermal protection systems made of ablative material. In order to properly model and predict the aerothermal environment of the vehicle, it is imperative to account for the gases produced by ablation processes. In the case of charring ablators, where an inner resin is pyrolyzed at a relatively low temperature, the composition of the gas expelled into the boundary layer is complex and may lead to thermal chemical reactions that cannot be captured with simple flow chemistry models. In order to obtain better predictions, an appropriate gas flow chemistry model needs …
Modeling Of Heat Transfer Attenuation By Ablative Gases During The Stardust Re-Entry,
2012
University of Kentucky
Modeling Of Heat Transfer Attenuation By Ablative Gases During The Stardust Re-Entry, Alexandre Martin, Iain D. Boyd
Mechanical Engineering Faculty Publications
The great majority of modern space vehicles designed for planetary exploration use ablative materials to protect the payload against the high heating environment experienced during re-entry. In order to properly model and predict the aerothermal environment of the vehicle, it is imperative to account for the gases produced by ablation processes. In the case of charring ablators, where an inner resin is pyrolyzed at a relatively low temperature, the composition of the gas expelled into the boundary layer is complex and may lead to thermal chemical reactions that cannot be captured with simple flow chemistry models. In order to obtain …
Effect Of Applied Magnetic Field On Shock Boundary Layer Interaction,
2012
University of Kentucky
Effect Of Applied Magnetic Field On Shock Boundary Layer Interaction, Ovais U. Khan, Alexandre Martin
Mechanical Engineering Faculty Publications
The governing magneto-hydrodynamic (MHD) equations contain classical fluid dynamics equations along with coupled Maxwell’s magnetic induction equations. These equations model both advection and diffusion effects of electromagnetic field. However, available literature indicates that some previous investigations neglect the diffusion of magnetic field and considered only ideal MHD equations for modeling a typical MHD problem. In this work, the effects of magnetic field diffusion term also known as viscous magnetic term have been investigated over flow structure. Low magnetic Reynolds number approximation and ideal full MHD set of equations have been considered and solved using a four-stage modified Runge-Kutta scheme augmented …
Defining, Teaching, And Assessing Engineering Design Skills,
2012
San Jose State University
Defining, Teaching, And Assessing Engineering Design Skills, Nikos J. Mourtos
Faculty Publications
The paper discusses a systematic approach for defining, teaching, and assessing engineering design skills. Although the examples presented in the paper are from the field of aerospace engineering, the principles apply to engineering design in general. What makes the teaching of engineering design particularly challenging is that the necessary skills and attributes are both technical and non-technical and come from the cognitive as well as the affective domains. Each set of skills requires a different approach to teach and assess. Implementing a variety of approaches for a number of years at SJSU has shown that it is just as necessary …
Encyclopedia Of Mathematics And Society: 'Engineering Design',
2012
University of Dayton
Encyclopedia Of Mathematics And Society: 'Engineering Design', Kimberly Edginton Bigelow
Mechanical and Aerospace Engineering Faculty Publications
Engineers design everything from automobiles and bridges to prosthetic limbs and sporting equipment. Designing is different from simply building in that it requires the adherence to a very systematic, yet iterative, process known as the “engineering design process.” This process is to engineers what the scientific method is to scientists-guiding steps that help ensure that the end result is the best it can be. When a new product is created without following the steps of the engineering design process, there is a higher likelihood that the product designed will lack some important aspect: the end product may not appropriately account …
Geochemical Evaluation Of High
Sulfate Levels In Ponca Creek,
Northeastern Nebraska,
2012
Air Force Center for Engineering and the Environment
Geochemical Evaluation Of High Sulfate Levels In Ponca Creek, Northeastern Nebraska, Jon C. Atkinson
United States Air Force: Publications
Most surface water and shallow groundwater occurring in northeastern Nebraska are of the calcium bicarbonate type, with minor concentrations (e.g., 10–200 mg/L) of sulfate (SO4). Examination of historical water quality data (major cations and anions) for Ponca Creek, a predominantly ephemeral streamin northeastern Nebraska, revealed that SO4 concentrations ranged from about 110 to almost 1000mg/L and contribute to a calcium sulfate hydrochemical facies. Consequently, most SO4 concentrations were above the U.S. Environmental Protection Agency secondary maximum contaminant level in drinking water of 250 mg/L. Sulfate concentrations for the same period for a nearby stream, Verdigre Creek, …
Specialized System Identification For Parafoil And Payload Systems,
2012
Georgia Institute of Technology - Main Campus
Specialized System Identification For Parafoil And Payload Systems, Michael Ward, Mark Costello, Nathan Slegers
Faculty Publications - Biomedical, Mechanical, and Civil Engineering
There are a number of peculiar aspects to parafoil and payload systems that make it difficult to apply conventional system identification procedures used for aerospace systems. Parafoil and payload systems are unique because typically there is very little sensor information available, the sensors that are available are separated from the canopy by a complex network of flexible rigging, the systems are very sensitive to wind and turbulence, the systems exhibit a number of nonlinear behaviors, and the systems exhibit a high degree of variability from flight to flight. The current work describes a robust system identification procedure developed to address …
Evaluation Of Multibody Parafoil Dynamics Using Distributed Miniature Wireless Sensors,
2012
University of Alabama - Huntsville
Evaluation Of Multibody Parafoil Dynamics Using Distributed Miniature Wireless Sensors, Chrystine M. Gorman, Nathan Slegers
Faculty Publications - Biomedical, Mechanical, and Civil Engineering
Guided parafoils arc composed of two primary bodies, a payload and parafoil. The payload encompasses the majority ofthe ovcrdll system mass; however, the parafoil generates the majority of aerodynamic loads and is the sole source of control. Despite the canopy being the source of control, the sensor systems used for guidance are located away from the parafoil. Many multi body models exist in literature and use different degrees of freedom to represent parafoil-payload relative motion. However, in many cases, simulations are used to investigate how the relative motion between bodies affects the overall dynamics without experimental validation determining the accuracy …
Ua94/6/8 Student / Alumni Personal Papers Wku Terry Wilcutt,
2012
Western Kentucky University
Ua94/6/8 Student / Alumni Personal Papers Wku Terry Wilcutt, Wku Archives
WKU Archives Collection Inventories
Records created by and about Terry Wilcutt and manned space flights.
Cfd Study On Aerodynamic Effects Of A Rear Wing/Spoiler On A Passenger Vehicle,
2012
Santa Clara University
Cfd Study On Aerodynamic Effects Of A Rear Wing/Spoiler On A Passenger Vehicle, Mustafa Cakir
Mechanical Engineering Master's Theses
Aerodynamic characteristics of a racing car are of significant interest in reducing car-racing accidents due to wind loading and in reducing the fuel consumption. At the present, modified car racing becomes more popular around the world. Sports cars are most commonly seen with spoilers, such as Ford Mustang, Subaru Impreza, and Chevrolet Corvette. Even though these vehicles typically have a more rigid chassis and a stiffer suspension to aid in high-speed maneuverability, a spoiler can still be beneficial. One of the design goals of a spoiler is to reduce drag and increase fuel efficiency. Many vehicles have a fairly steep …
Vision-Based Testbeds For Control System Applicaitons,
2012
University of Central Florida
Vision-Based Testbeds For Control System Applicaitons, Robert Sivilli
Electronic Theses and Dissertations
In the field of control systems, testbeds are a pivotal step in the validation and improvement of new algorithms for different applications. They provide a safe, controlled environment typically having a significantly lower cost of failure than the final application. Vision systems provide nonintrusive methods of measurement that can be easily implemented for various setups and applications. This work presents methods for modeling, removing distortion, calibrating, and rectifying single and two camera systems, as well as, two very different applications of vision-based control system testbeds: deflection control of shape memory polymers and trajectory planning for mobile robots. First, a testbed …
Passive Wireless Antenna Sensors For Crack Detection And Shear/Compression Sensing,
2012
University of Texas at Arlington
Passive Wireless Antenna Sensors For Crack Detection And Shear/Compression Sensing, Irshad Mohammad
Mechanical and Aerospace Engineering Dissertations - Archive
Despite the fact that engineering components and structures are carefully designed against fatigue failures, 50 to 90% of mechanical failures are due to fatigue crack formation. The severity of the failure depends on both the crack length and its orientation with respect to the loading direction. Many types of sensors are available that can detect fatigue crack propagation. But, crack orientation detection has been rarely reported in the literature. We evaluated a patch antenna sensor capable of detecting crack propagation as well as crack orientation changes. The aim of the sensors would be to evaluate the real-time health condition of …
Illustration Of Fundamentals Of Mechanical Vibration Using Computable Document Format,
2012
University of Texas at Arlington
Illustration Of Fundamentals Of Mechanical Vibration Using Computable Document Format, Shiva Deshmukh
Mechanical and Aerospace Engineering Theses - Archive
The main objective of this study is focused on the better understanding of the basic concepts of mechanical vibrations and its free and ready availability to the entire student community all over the globe.In this study the concepts of vibrations are projected in the form of mathematical models. The mathematical models are designed using MATHEMATICA. These models are graphical in nature and can be animated at will. They are compiled and converted to the Computable Document Format referred as CDF.A very special function Manipulate is used in making the models. This function has given the models an ability to compute …
Graph Theoretic Framework Based Cooperative Control And Estimation Of Multiple Uavs For Target Tracking,
2012
University of Texas at Arlington
Graph Theoretic Framework Based Cooperative Control And Estimation Of Multiple Uavs For Target Tracking, Mousumi Ahmed
Mechanical and Aerospace Engineering Dissertations - Archive
Designing the control technique for nonlinear dynamic systems is a significant challenge. Approaches to designing a nonlinear controller are studied and an extensive study on backstepping based technique is performed in this research with the purpose of tracking a moving target autonomously. Our main motivation is to explore the controller for cooperative and coordinating unmanned vehicles in a target tracking application.To start with, a general theoretical framework for target tracking is studied and a controller in three dimensional environment for a single UAV is designed. This research is primarily focused on finding a generalized method which can be applied to …
