An Experimental Study On The Effects Of Blade Row Interactions On Aerodynamic Loss Mechanisms In A Multistage Compressor,
2015
Purdue University
An Experimental Study On The Effects Of Blade Row Interactions On Aerodynamic Loss Mechanisms In A Multistage Compressor, Natalie Rochelle Smith
Open Access Dissertations
While the gas turbine engine has existed for nearly 80 years, much of the complex aerodynamics which governs compressor performance is still not well understood. The unsteady flow field consists of periodic blade row interactions from the wakes and potential fields of each blade and vane. Vane clocking is the relative circumferential indexing of adjacent vane rows with the same vane count, and it is one method to change blade row interactions. Though the potential of performance benefits with vane clocking is known, the driving flow physics have yet to be identified. ^ This research examines the effects of blade …
The Panther: 2015 Aiaa Design Build Fly,
2015
Embry-Riddle Aeronautical University
The Panther: 2015 Aiaa Design Build Fly, Bryce Milnes, Chris Crawford
Publications
The ERAU Prescott chapter of AIAA participated in the 2015 AIAA Design Build Fly competition at Raytheon Missile Systems in Tucson from April 10-12. A remote controlled aircraft meeting and exceeding all competition performance requirements was designed and fabricated by the 30+ students of the team. Additionally, a 60 page report was submitted detailing the project starting from initial considerations and advancing through flight test verification of aircraft capabilities. The success of this project was enabled by the E-Prize and SGA funding received to support our efforts throughout the year. The lessons learned regarding management and planning, engineering design approaches, …
Unmanned Aerial Vehicle (Uav) Propulsion Research: Conceptual Studies Of “Ultra-Compact Shaft-Less Jet Engines” For Next Generation Uavs,
2015
Embry-Riddle Aeronautical University
Unmanned Aerial Vehicle (Uav) Propulsion Research: Conceptual Studies Of “Ultra-Compact Shaft-Less Jet Engines” For Next Generation Uavs, Tyler Eiguren, Trevor Douglas, Tre Buchanan
Publications
Unmanned Aerial Vehicles are becoming more commonly used in today’s society, ranging anywhere from military applications to entertainment for enthusiasts and hobbyists. The complexity of current generation UAV’s propulsive devices, based upon a scaled turbine engine and separate gas & electrically powered rotating fan blades, require regular maintenance for every 24 hours of flight. This added cost coupled with necessary intricate machinery deters UAV designers from such engines, leaving a void in current production. Our research team believes that by combining a simplified alternative compression & combustion process with an electrically driven fan, we can develop an energy efficient, reliable, …
Multi-Segment Foot Joint Kinematics With Varying Midfoot Orthotic Postings,
2015
University of Dayton
Multi-Segment Foot Joint Kinematics With Varying Midfoot Orthotic Postings, Hilary F. Feskanin
Honors Theses
Foot orthoses are often prescribed to prevent and treat lower limb disorders. While the success of these devices is well documented, the mechanisms behind them are unclear. Due to methodological limitations, many studies have focused on the rearfoot. This is the first study to assess the effects of midfoot-targeted orthotic strategies on midfoot and rearfoot kinematics. Gait mechanics were recorded for 19 healthy females walking in four orthotic conditions: valgus midfoot post, varus midfoot post, heel lift and standard/control. The midtarsal and ankle joint 3D kinematics for the three experimental conditions were compared to the control condition. Variables of interest …
Is Aerospace Important To The United States?,
2015
Omaha North High Magnet School
Is Aerospace Important To The United States?, Joshua Romer
Nebraska College Preparatory Academy: Senior Capstone Projects
Aerospace is technology and industry in space flight and avia:on. It provides safe and faster means of transporta:on, explora:on, and electronics. Aerospace is responsible for many US exports and improvements. Aerospace is important to research because of its lack of publicity.
Analysis Of A Hybrid Rocket Burn Using Generalized Compressible Flow,
2015
Embry-Riddle Aeronautical University
Analysis Of A Hybrid Rocket Burn Using Generalized Compressible Flow, Naveen Sri Uddanti
Doctoral Dissertations and Master's Theses
The analysis of square ports in a hybrid rocket is simple when compared to other complicated port geometries such as a wagon wheel configuration. In the present work, fuel grains with several ports in a hybrid rocket engine are analyzed by transforming the ports into equivalent square ports. As an example, the internal ballistics of a hybrid rocket with circular ports is analyzed by transforming it to an equivalent solid grain with square ports having the same amount of solid fuel and burn time. The results obtained are similar to that of circular port but with a slight decrease in …
Comprehensively Simulating The Mixed-Mode Progressive Delamination In Composite Laminates,
2015
Purdue University
Comprehensively Simulating The Mixed-Mode Progressive Delamination In Composite Laminates, Zhenyuan Gao
Open Access Theses
Delamination, or interlaminar debonding, is a commonly observed failure mechanism in composite laminates. It is of great significance to comprehensively simulate the mixed-mode progressive delamination in composite structures because by doing this, people can save a lot of effort in evaluating the safe load which a composite structure can endure.^ The objective of this thesis is to develop a numerical approach to simulating double-cantilever beam (DCB) and mixed-mode bending (MMB) tests and also of specifying/validating various cohesive models. A finite element framework, which consists of properly selecting time integration scheme (explicit dynamic), viscosity, load rate and mass scaling, is developed …
Air Traffic Management Under Uncertain Weather Impact,
2015
Purdue University
Air Traffic Management Under Uncertain Weather Impact, Le Gao
Open Access Theses
Air traffic management under uncertain weather impact is a difficult problem. In this thesis, by dividing the whole air traffic systems into small cells, a new method using database to integrate weather and flight data is proposed. An algorithm has been developed to project weather data onto cells. This research also uses a predictive view to find ights which are affected by severe weather. And a prototype detour algorithm is applied on those flights based on the status information of each cell.
Considerations For Nondestructive Evaluation Of Discontinuous Fiber Composites Using Dynamic Analysis,
2015
Purdue University
Considerations For Nondestructive Evaluation Of Discontinuous Fiber Composites Using Dynamic Analysis, Rebecca A. Cutting
Open Access Theses
Knowledge of the composite microstructure is vital to predicting performance of the structural member. However, depending on the manufacturing process, the microstructure of the part may be unknown and not predictable with simulation software. A few non-destructive evaluation techniques have been adjusted to predict fiber orientation of composites, including CT scans and thermography, but none have proven acceptable on a large scale with the amount of fidelity required. This research investigated the use of dynamic analysis as a non-destructive evaluation technique to predict fiber orientation of discontinuous fiber compression molded parts. While the method is currently unable to predict individual …
Performance Analysis Of Vortex Based Mixers For Confined Flows,
2015
Purdue University
Performance Analysis Of Vortex Based Mixers For Confined Flows, Timo Buschhagen
Open Access Theses
The hybrid rocket is still sparsely employed within major space or defense projects due to their relatively poor combustion efficiency and low fuel grain regression rate. Although hybrid rockets can claim advantages in safety, environmental and performance aspects against established solid and liquid propellant systems, the boundary layer combustion process and the diffusion based mixing within a hybrid rocket grain port leaves the core flow unmixed and limits the system performance. One principle used to enhance the mixing of gaseous flows is to induce streamwise vorticity. The counter-rotating vortex pair (CVP) mixer utilizes this principle and introduces two vortices into …
Effect Of Electrode Geometry On High Energy Spark Discharges In Air,
2015
Purdue University
Effect Of Electrode Geometry On High Energy Spark Discharges In Air, Mounia Belmouss
Open Access Theses
The government, aerospace, and transportation industries are deeply invested in developing new technologies to improve the performance and maneuverability of current and future aircraft while reducing aerodynamic noise and environmental impact. One of the key pathways to meet these goals is through aerodynamic flow control, which can involve suppressing or inducing separation, transition and management of turbulence in boundary layers, increasing the lift and reducing the drag of airfoils, and gas mixing to control fluctuating forces and aerodynamic noise [1]. In this dissertation, the complex flow field following a spark discharge is studied for a range of geometries and discharge …
Asymptotic Modelling Of A Thermopiezoelastic Anisotropic Smart Plate,
2015
Purdue University
Asymptotic Modelling Of A Thermopiezoelastic Anisotropic Smart Plate, Yufei Long
Open Access Theses
Motivated by the requirement of modelling for space flexible reflectors as well as other applications of plate structures in engineering, a general anisotropic laminated thin plate model and a monoclinic Reissner-Mindlin plate model with thermal deformation, two-way coupled piezoelectric effect and pyroelectric effect is constructed using the variational asymptotic method, without any ad hoc assumptions. Total potential energy contains strain energy, electric potential energy and energy caused by temperature change. Three-dimensional strain field is built based on the concept of warping function and decomposition of the rotation tensor. The feature of small thickness and large in-plane dimension of plate structure …
Flexible Weapons Architecture Design,
2015
Purdue University
Flexible Weapons Architecture Design, William C. Pyant
Open Access Theses
Present day air-delivered weapons are of a closed architecture, with little to no ability to tailor the weapon for the individual engagement. The closed architectures require weaponeers to make the target fit the weapon instead of fitting the individual weapons to a target. The concept of a flexible weapons aims to modularize weapons design using an open architecture shell into which different modules are inserted to achieve the desired target fractional damage while reducing cost and civilian casualties. This thesis shows that the architecture design factors of damage mechanism, fusing, weapons weight, guidance, and propulsion are significant in enhancing weapon …
Dynamics Of Transitions Between Capillary Stable States Under Weightlessness,
2015
Purdue University
Dynamics Of Transitions Between Capillary Stable States Under Weightlessness, Praveen Srikanth
Open Access Theses
The study of two phase systems with one of the phases obstructing the other is of importance in a lot of fields. Liquid droplets in airways and air bubbles in the blood stream both fall under this category of problems. Helium bubbles in hydrazine fuel lines of satellites also have been found to cause frequent thruster shutdown and also seriously affect spacecraft control. Studies have been carried out until now to look at static equilibrium topologies and stability of such two phase systems in straight, bent and laterally compressed capillaries. In this investigation we look at the dynamics of the …
Ads-B Used In Improvement Of Air Traffic Control,
2015
Purdue University
Ads-B Used In Improvement Of Air Traffic Control, Hao Wang
Open Access Theses
Automatic dependent surveillance – broadcast (ADS-B) is a central component of the NextGen air traffic control program. This surveillance technology can replace current secondary surveillance radars (SSR) and improve cockpit situational awareness. The service can improve traffic surveillance capabilities by sharing accurate aircraft position information between pilots and air traffic controllers. In addition, ADS-B provides pilots with weather as well as air traffic information for nearby area. In order to receive these traffic and weather services, a pilot must have appropriate onboard equipment including GPS receiver, Universal Access Transceiver, antenna and multi-function cockpit display which is capable of receiving and …
Linear Matrix Inequality-Based Nonlinear Adaptive Robust Control With Application To Unmanned Aircraft Systems,
2015
Purdue University
Linear Matrix Inequality-Based Nonlinear Adaptive Robust Control With Application To Unmanned Aircraft Systems, David William Kun
Open Access Theses
Unmanned aircraft systems (UASs) are gaining popularity in civil and commercial applications as their lightweight on-board computers become more powerful and affordable, their power storage devices improve, and the Federal Aviation Administration addresses the legal and safety concerns of integrating UASs in the national airspace. Consequently, many researchers are pursuing novel methods to control UASs in order to improve their capabilities, dependability, and safety assurance. The nonlinear control approach is a common choice as it offers several benefits for these highly nonlinear aerospace systems (e.g., the quadrotor). First, the controller design is physically intuitive and is derived from well known …
Loss Of Accuracy Using Smeared Properties In Composite Beam Modeling,
2015
Purdue University
Loss Of Accuracy Using Smeared Properties In Composite Beam Modeling, Ning Liu
Open Access Theses
Advanced composite materials have broad, proven applications in many engineering systems ranging from sports equipment sectors to components on the space shuttle because of their lightweight characteristics and significantly high stiffness. Together with this merit of composite materials is the challenge of improving computational simulation process for composites analysis. Composite structures, particularly composite laminates, usually consist of many layers with different lay-up angles. The anisotropic and heterogeneous features render 3D finite element analysis (FEA) computationally expensive in terms of the computational time and the computing power. ^ At the constituent level, composite materials are heterogeneous. But quite often one homogenizes …
Real-Time Rss-Based Indoor Navigation For Autonomous Uav Flight,
2015
Purdue University
Real-Time Rss-Based Indoor Navigation For Autonomous Uav Flight, Sangjun Lee
Open Access Theses
Navigation for the autonomous flight of Unmanned Aerial Vehicles (UAVs) in an indoor space has attracted much attention recently. One of the main goals of an indoor navigation system is developing an alternative method to obtain position information that can replace or complement the global positioning system. While much research has focused on vision-based indoor navigation systems, this paper aims to develop a Received Signal Strength (RSS)-based navigation system, which is a more cost effective alternative. Then, the position and attitude of a UAV can be computed by the fusion of RSS measurements and measurements from the onboard inertial measurement …
Design Of Transfers From Earth-Moon L 1/L2 Libration Point Orbits To A Destination Object,
2015
Purdue University
Design Of Transfers From Earth-Moon L 1/L2 Libration Point Orbits To A Destination Object, Masaki Kakoi
Open Access Dissertations
Within the context of both manned and robotic spaceflight activities, orbits near the Earth-Moon L1 and L2 libration points could support lunar surface operations and serve as staging areas for future missions to near-Earth asteroids as well as Mars. In fact, an Earth-Moon L2 libration point orbit has been proposed as a potential hub for excursions to Mars as well as activities in support of planetary exploration. Yet, the dynamical environment within the Earth-Moon system is complex and, consequently, trajectory design in the vicinity of Earth-Moon L1 and L2 is nontrivial. Routine transfers between an Earth-Moon L1/L2 facility and Mars …
Design Of Low-Thrust Missions To Asteroids With Analysis Of The Missed-Thrust Problem,
2015
Purdue University
Design Of Low-Thrust Missions To Asteroids With Analysis Of The Missed-Thrust Problem, Frank E. Laipert
Open Access Dissertations
Small bodies in the Solar System, such as asteroids and dwarf planets, are ideal targets for electric propulsion missions because of the high delta-V required to rendezvous with these targets. We study trajectories to the asteroid belt, including a human mission to Ceres and a sample return mission to (216) Kleopatra, along with trajectories to the Jupiter Trojan asteroids. For the human mission to Ceres, payload masses of 75 Mg are achievable with a 11.7 MW nuclear electric propulsion system and an initial mass in LEO of 289 Mg. For low-thrust sample return missions to the main belt asteroid Kleopatra, …
