Battery Centric Serial Hybrid Aircraft Performance And Design Space,
2017
Embry-Riddle Aeronautical University
Battery Centric Serial Hybrid Aircraft Performance And Design Space, Lenny Gartenberg
Doctoral Dissertations and Master's Theses
The design space and flight envelope of a battery centric serial hybrid aircraft has been analytically derived. The formulation assumes cruising flight only and all energy available is used. The flight envelope can be generated for any conventional propeller driven serial hybrid aircraft. The advantageous combination of an electric motor and controllable-pitch electric propeller was also explored. The results are used to be able to control efficiency and noise at constant thrust and therefore constant airspeed. Manufacturer provided electric motor and propeller data is used for efficiency purposes. Since the electric motor is virtually silent compared to the propeller, published …
Comparison Of Rans Modeling To Dual-Plane Piv Measurements Of The Turbulent Tip Vortex Trailed From A Hovering Rotor,
2017
Embry-Riddle Aeronautical University
Comparison Of Rans Modeling To Dual-Plane Piv Measurements Of The Turbulent Tip Vortex Trailed From A Hovering Rotor, Zachary Lietzau
Doctoral Dissertations and Master's Theses
Numerical simulations using the Reynolds-Averaged Navier-Stokes (RANS) equations were conducted to study the development and turbulent decay of the tip vortices in the wake produced by a hovering rotor. The computational results were compared to detailed, dual plane Particle Image Velocimetry (PIV) measurements of a turbulent tip vortex trailed from a single-bladed rotor. The work investigated both the required mesh resolution and most suitable turbulence closure models with rotational/curvature corrections by assessing their predictions of the tip vortex properties and the overall physical nature of the rotor wake. It was found that even when using a higher-order accurate central differencing …
The Issues And Complexities Surrounding The Future Of Long Duration Spaceflight,
2017
Embry-Riddle Aeronautical University
The Issues And Complexities Surrounding The Future Of Long Duration Spaceflight, Solomon Miiro
Graduate Student Works
The Comprehensive Exam put forward by this proposal is intended to address the learning objectives covered by the Master of Aeronautical Science Degree with specializations in Aviation Aerospace Safety Systems and some limited aspects in Human Factors in Aviation Systems. This will be accomplished by researching the following topics: effects of long duration spaceflight on crew performance and functioning and the steps that should be taken to enable long term spaceflight mission crews in lieu of accomplishing important missions; a human factor analysis should current human-machine design interfaces be enhanced to make manual rendezvous and docking in space easier to …
Actuator Disk Theory For Compressible Flow,
2017
California Polytechnic State University, San Luis Obispo
Actuator Disk Theory For Compressible Flow, Htet Htet Nwe Oo
Master's Theses
Because compressibility effects arise in real applications of propellers and turbines, the Actuator Disk Theory or Froude’s Momentum Theory was established for compressible, subsonic flow using the three laws of conservation and isentropic thermodynamics. The compressible Actuator Disk Theory was established for the unducted (bare) and ducted cases in which the disk was treated as the only assembly within the flow stream in the bare case and enclosed by a duct having a constant cross-sectional area equal to the disk area in the ducted case. The primary motivation of the current thesis was to predict the ideal performance of a …
2017 Spring Graduate Recognition Program,
2017
The University of Alabama in Huntsville
2017 Spring Graduate Recognition Program, Propulsion Research Center, Robert Frederick
PRC Graduate Recognition
This program includes the graduate recognition program for spring 2017. Includes photographs, upcoming events, recent publications, and student profiles.
Single Waypoint Zem/Zev Based Closed-Loop Controller Design For Rendezvous With A Rotating Target,
2017
Florida Institute of Technology
Single Waypoint Zem/Zev Based Closed-Loop Controller Design For Rendezvous With A Rotating Target, Armando Alvarez Rolins
Theses and Dissertations
The research presented in this thesis addresses a very specific kind of autonomous rendezvous procedure between two spacecraft in close proximity, namely that in which the chaser object is attempting to dock at a location on a rotating target which is tracing a circle perpendicular to the axis of rotation. The approaches that have been mentioned in literature which focus on this specific condition make use of offline optimization algorithms to plot the trajectory of the chaser and use closed-loop control to follow that trajectory. This method is computationally demanding and does not allow for feedback in the desired boundary …
Application Of Strand-Cartesian Interfaced Solver On Flows Around Various Geometries,
2017
Utah State University
Application Of Strand-Cartesian Interfaced Solver On Flows Around Various Geometries, Yushi Yanagita
All Graduate Plan B and other Reports, Spring 1920 to Spring 2023
This work examines the application of a high-order numerical method to strand-based grids to solve the Navier-Stokes equations. Coined "Flux Correction", this method eliminates error terms in the fluxes of traditional second-order finite volume Galerkin methods. Flux Correction is first examined for applications to the Reynolds-Averaged Navier-Stokes equations to compute turbulent flows on a strictly strand-based domain. Flow over three geometries are examined to demonstrate the method’s capabilities: a three-dimensional bump, an infinite wing, and a hemisphere-cylinder configuration. Comparison to results obtained from established codes show that the turbulent Flux Correction scheme accurately predicts flow properties such as pressure, velocity …
Takeoff And Landing Distance Measurement: An Evaluation Of Laser Altimetry For The Collection Of Absolute Aircraft Altitude,
2017
Florida Institute of Technology
Takeoff And Landing Distance Measurement: An Evaluation Of Laser Altimetry For The Collection Of Absolute Aircraft Altitude, Christopher John Kennedy
Theses and Dissertations
The measurement of takeoff and landing distance during flight testing of general aviation aircraft requires the accurate measurement of aircraft position over the ground and altitude up to 50 feet above surface elevation. Current methods of evaluating takeoff and landing distances include cinetheodolites, laser and radar trackers, and Differential Global Positioning Systems (DGPS). The use of laser altimetry to range altitude above the ground originated with military and agricultural aircraft. The AgLaser laser module was an infrared laser ranging unit designed for agricultural aircraft to gauge optimal spray height above a field. The AgLaser system has a stated accuracy of …
Structural Design Of A Business Jet Winglet,
2017
Embry-Riddle Aeronautical University
Structural Design Of A Business Jet Winglet, Jaime Gutierrez
Doctoral Dissertations and Master's Theses
Structural sizing of a winglet for the Falcon 10 was performed and is presented here. The aerodynamic profile of the winglet was taken from a previous study, which predicted an increase in range of 3.3% with an estimated weight increase of 52 kg. An investigation of the current structure layouts and materials used in the industry was conducted. Six loading cases were analyzed to identify the most critical for the winglet, found to be negative and positive sideslip and gust. A finite element model was developed and used to size the structure. A fabrication process and assembly is described and …
Extended Surface Heat Transfer Coefficients Via Endwall Temperature Measurements,
2017
Embry-Riddle Aeronautical University
Extended Surface Heat Transfer Coefficients Via Endwall Temperature Measurements, Yogesh Pai
Doctoral Dissertations and Master's Theses
Short pins are used for internal cooling of the trailing edge in a gas turbine blade. A novel method is described in this thesis which helps in simplifying the experimental process used to obtain average heat transfer data on the pin surface, at the expense of additional post processing complexity. The method is based on a unique, analytical solution of the longitudinal conduction equation with internal heat generation, allowing computation of heat transfer rates via pin base temperature measurements via Temperature Sensitive Paint, or similar non-intrusive methods. Verification of this method is done with comparisons to the solution of infinite …
The Effect Of Surface Materials And Morphology On Wingsuit Aerodynamics,
2017
Embry-Riddle Aeronautical University
The Effect Of Surface Materials And Morphology On Wingsuit Aerodynamics, Timothy Allen Sestak
Doctoral Dissertations and Master's Theses
This study examines the aerodynamic effects of the materials, textiles, and morphologies currently used in wingsuit design and construction. The experiment was a low-speed wind tunnel investigation using a rigid wing with an aspect ratio of 2, a NACA 4418 airfoil cross section and a smooth, polished painted surface as a baseline. The baseline wing was modified by covering the upper and lower surfaces with various textiles currently used in wingsuit construction. This study is the first step in continued research to design and build a wingsuit with superior glide performance compared to current designs. Surface textures and features on …
A Performance And Visualization Study On Inlet Geometries Of A Cross-Flow Fan.,
2017
University of Louisville
A Performance And Visualization Study On Inlet Geometries Of A Cross-Flow Fan., Yoel Tanquero
Electronic Theses and Dissertations
A study was conducted to characterize the flow-field in the suction region of different inlet geometries of a cross-flow fan. The characterization was accomplished by correlating the static performance curves measured for each fan-inlet configuration to the streamline plot obtained using a particle tracking velocimetry (PTV) measurement system at three constant flow rates (25, 40, and 55 CFM). The PTV measurement system used was developed by the author and uses helium bubbles as tracers, an LED light sheet, a slow motion camera, and a Matlab program. Four inlet geometry design variables were defined and independently studied to evaluate the effect …
Evaluation Of Flux Correction On Three-Dimensional Strand Grids With An Overset Cartesian Grid,
2017
Utah State University
Evaluation Of Flux Correction On Three-Dimensional Strand Grids With An Overset Cartesian Grid, Dalon G. Work
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Simulations of fluid flows over complex geometries are typically solved using a solution technique known as the overset meshing method. The geometry is meshed using grid types appropriate to the local geometry in a patchwork fashion, rather than meshing the entire geometry with one type of mesh. The strand-Cartesian approach is a simplification of this process. While high-order accurate solvers on Cartesian grids are simple to implement, strand grids are usually restricted to second-order accuracy, resulting in poor quality solutions. Flux correction is a high-order accurate solution method, specifically designed for use on strand grids. The flux correction method on …
Characterization Of The Thermal Resistance Of Grain Boundaries Of Cerium Oxide,
2017
Utah State University
Characterization Of The Thermal Resistance Of Grain Boundaries Of Cerium Oxide, Jesse Spackman
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Many materials are made up of small crystals, or grains. Grain boundaries are the interfaces between two grains and affect the flow of heat through the material. These interfaces serve to interfere with the energy carriers by scattering or disrupting them. Because of the negative effect these interfaces have on these energy carriers, they inhibit heat flow and act as thermal resistors. The thermal boundary resistance between two grains of the same material is sometimes referred to as the Kapitza resistance, although this term is also used to describe the thermal resistance between solid/solid interfaces of different materials or solid/liquid …
Water Entry Impact Dynamics Of Diving Birds,
2017
Utah State University
Water Entry Impact Dynamics Of Diving Birds, Saberul Islam Sharker
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Plunge diving and surface diving are two main techniques used by seabirds for foraging purposes. While some plunge divers can dive into the water at very high speeds (24 m/s), surface divers do not. This study analyzes the free-surface impact of 3D printed bird head models with embedded accelerometers to determine why surface divers cannot dive safely at high speeds. The problem is investigated in the context of impact jerk where surface divers, unlike plunge divers, are found to experience non-dimensional jerk (J∗) values exceeding a safe limit. This approach portrays itself as an unconventional yet effective method …
Mechanical Performance Of Natural / Natural Fiber Reinforced Hybrid Composite Materials Using Finite Element Method Based Micromechanics And Experiments,
2017
Utah State University
Mechanical Performance Of Natural / Natural Fiber Reinforced Hybrid Composite Materials Using Finite Element Method Based Micromechanics And Experiments, Muhammad Ziaur Rahman
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
A micromechanical analysis of the representative volume element (RVE) of a unidirectional flax/jute fiber reinforced epoxy composite is performed using finite element analysis (FEA). To do so, first effective mechanical properties of flax fiber and jute fiber are evaluated numerically and then used in evaluating the effective properties of flax/jute/epoxy hybrid composite. Mechanics of Structure Genome (MSG), a new homogenization tool developed in Purdue University, is used to calculate the homogenized effective properties. Numerical results are compared with analytical solution based on rule of mixture, Halpin-Tsai as well as Tsai-Hahn equations. The effect of the volume fraction of the two …
A Survey And Performance Analysis Of Orbit Propagators For Leo, Geo, And Highly Elliptical Orbits,
2017
Utah State University
A Survey And Performance Analysis Of Orbit Propagators For Leo, Geo, And Highly Elliptical Orbits, Simon P. Shuster
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
On-orbit targeting, guidance, and navigation relies on state vector propagation algorithms that must strike a balance between accuracy and computational efficiency. To better understand this balance, the relative position accuracy and computational requirements of numerical and analytical propagation methods are analyzed for a variety of orbits. For numerical propagation, several differential equation formulations (Cowell, Encke-time, Encke-beta, and Equinoctial Elements) are compared over a range of integration step sizes for a given set of perturbations and numerical integration methods. This comparison is repeated for two numerical integrators: a Runge-Kutta 4th order and a NLZD4/4. For analytical propagation, SGP4, which relies on …
Multidisciplinary Shape Optimization Of A Composite Blended Wing Body Aircraft,
2017
University of South Carolina
Multidisciplinary Shape Optimization Of A Composite Blended Wing Body Aircraft, Charles Maxwell Boozer
Theses and Dissertations
A multidisciplinary shape optimization tool coupling aerodynamics, structure, and performance was developed for battery powered aircraft. Utilizing high-fidelity computational fluid dynamics analysis tools and a structural wing weight tool, coupled based on the multidisciplinary feasible optimization architecture; aircraft geometry is modified in the optimization of the aircraft’s range or endurance. The developed tool is applied to three geometries: a hybrid blended wing body, delta wing UAS, the ONERA M6 wing, and a modified ONERA M6 wing. First, the optimization problem is presented with the objective function, constraints, and design vector. Next, the tool’s architecture and the analysis tools that are …
Implementing Delay-Tolerant Networking At Morehead State University,
2017
Morehead State University
Implementing Delay-Tolerant Networking At Morehead State University, Nathaniel J. Richard
Morehead State Theses and Dissertations
A thesis presented to the faculty of the College of Science at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science by Nathaniel J. Richard on April 28, 2017.
Flying Simple Experiments In Space,
2017
Morehead State University
Flying Simple Experiments In Space, Robert J. Twiggs
Robert "Bob" Twiggs STEM Education Collection
A PowerPoint presentation created by Professor Bob Twiggs titled "Flying Simple Experiments in Space" from April 28, 2017.
