Engineering Commons^™

An Automated Optimal Design Of A Fan Blade Using An Integrated Cfd/Mdo Computer Environment, Uyi O. Idahosa

Master's Theses - Daytona Beach

The objective of the investigation is the development of more efficient design methodologies based on the applications of established design tools including Computational Fluid Dynamics (CFD) and non-linear Multidisciplinary Design Optimization (MDO) algorithms. Well known evolutionary type optimization algorithms include the Particle Swarm Optimization (PSO), Response Surface Optimization (RSO) and Genetic (GA) Algorithms. The benchmark case study is the optimal design of a low speed fan for an industrial air-conditioning application using the Response Surface Optimization (RSO) algorithm.

The optimization algorithm controls the variations of parameters that describe the three-dimensional geometry of the blade while applying performance and geometrical constraints …

Effect Of Sound Cue Frequency Filters On Front/Back Localization Performance For Three-Dimensional Verbal And Non-Verbal Warnings, Angelica A. Hernandez

Master's Theses - Daytona Beach

In aviation, as technology becomes more advanced and more demands are placed on the human operator, warnings have become an important part of display design. Although warnings have made a significant contribution to safety, problems still plague their design. Recent technological advances have been able to give sounds and warnings a three-dimensional quality (3D). This technology enables a person to perceive sound from any direction around the listener without having the sound physically come from that direction. Three-dimensional sounds have been shown to improve target acquisition and collision avoidance in flight (Oving & Bronkhorst, 1999), and may have other future …

Tools For Analysis Of Complex Geometries For A Combined Cycle Scram Jet / Rocket, James Moss

Master's Theses - Daytona Beach

A preliminary design for a variable geometry combined cycle supersonic combustion ram jet (SCRAM jet) / rocket was developed. A precise geometry was selected by parametric analysis and the resultant geometry was analyzed using a computational fluid dynamics (CFD) code developed by Dr. Eric Perrell, and modified by, among others, the author.

This paper is broken into several sections discussing, separately, the design innovations used to permit the geometry of the craft to be adjusted to conform to its flight conditions, the 2D analysis tool developed for the parametric analysis, development of the grid for CFD analysis, and modifications made …

Perceived Competence Of Aging Pilots, Laura M. Stelmach

Master's Theses - Daytona Beach

This study investigated the relationship between age and the perception of competence of pilots by the traveling public. Scenarios were utilized that depicted an airline captain successfully landing an airplane amidst adverse conditions. Scenarios varied only by the age of the Captain: Young, Old, or Unspecified Age and that the Young and Old scenarios included a photo of the captain. Perceived effectiveness, competence, avoidance, blame, and attribution as depicted by the Captain's performance in the scenario were assessed by 180 participants in three age groups (18-34, 35-55, and 56 <). Results showed that pilot age is a factor in perceived competence of pilots as well as participant age.

Using Scenario-Based Training To Teach Single Pilot Resource Management Related To The Use Of The Brs Parachute, Shayna Danielle Strally

Master's Theses - Daytona Beach

The Ballistic Recovery System is an emergency parachute for single engine aircraft which, when released, lowers the aircraft to the ground to prevent terrain collision. This study sought to examine the effects of scenario-based training on pilot’s use of the BRS. Of particular interest was the point at which the pilot decides to deploy the BRS. Single pilot resource management was included as a training objective, as it encompasses relevant cognitive skills such as decision making and situational awareness. The results showed participants in the scenario-based training condition performed significantly better than participants in a traditional training condition on several …

Maneuvering Control Of A Spacecraft With Propellant Sloshing, Philip A. Savella

Master's Theses - Daytona Beach

Propellant slosh has been a problem studied in spacecraft designs since the early days of large, liquid-fuel rockets. The conventional design solution involves physical structures inside the fuel tanks that limit propellant motion. Although effective, baffles and bladders add to spacecraft mass and structural complexity. In this research, the sloshing fuel mass is treated as an unactuated degree of freedom within a rigid body. Specifically, the propellant is modeled as a pendulum mass anchored at the center of a spherical tank. After obtaining the coupled equations of motion, several linear controllers are developed to achieve planar spacecraft pitch-maneuvers while suppressing …

Derivation Of A Numerical Method For Computing 3-D Magnetoplasmadynamic Flows In Thermodynamic Non-Equilibrium, Caroline Cecile Marcelle Liron

Master's Theses - Daytona Beach

Various models exist for the propulsion concept using magnetohydrodynamics (MHD). Various authors, such as Powell, Canupp, Candler, and MacCormack have dealt with issues of solving the magnetic field induction equations simultaneously with Navier-Stokes equations using Computational Fluid Dynamics (CFD). Although most authors deal with species non-equilibrium and thermal non-equilibrium, a new emphasis is set to study the impact of electrons with the electron energy and the electronic excitation energy, as well as a complex energy non-equilibrium.

This thesis presents the derivation of a numerical method for computing 3-D MHD flows for the purpose of modeling steady-state magnetoplasma …

Fabrication And Compressive Yield Strength Of Open Cell Corrugated Cellular Solids, Jeong Ho Choi

Master's Theses - Daytona Beach

This thesis studied the fabrication and compressive yield strength of open cell corrugated cellular solids made from type 304 stainless steel. Test samples were made by corrugating woven wire meshes, then laminating these in a high temperature argon environment. Mesh sizes ranging from 9.5 pore/cm (24 pore/in) to 31.5 pore/cm (80 pore/in) with wire diameters ranging from 0.178 mm (0.007 in) to 0.3556 mm (0.014 in) were bonded using lithobraze 925 (Ag-7.5Cu-0.2Li) to create cellular solids having relative densities ranging from 0.0384 to 0.0920. Test samples were then quasistatically compressed to measure the stress-strain response. The stress level at 25% …

Modeling And Slew-Maneuver Control Of A Flexible Spacecraft, Jeremy E. Eckhart

Master's Theses - Daytona Beach

Slew-maneuver control problem is studied for a flexible spacecraft consisting of a rigid main body to which a long flexible appendage is attached. Nonlinear dynamical system models are developed using both distributed parameter modeling and discrete parameter modeling; these models are shown to be equivalent for appropriately chosen system parameters. Lyapunov-based nonlinear feedback controllers are designed for the control of rigid-body motion while suppressing the lowest frequency vibrational mode. In case of large-angle maneuvers, these nonlinear controllers are shown to outperform the linearization-based controllers including the filtered proportional-derivative (PD) controllers as well as the linear quadratic regulator (LQR) controllers. Finally, …

Investigation Of A Highly Loaded, High Pressure Ratio Axial Turbine Stage For Industrial Applications, Amit Garg

Master's Theses - Daytona Beach

The turbine component of a gas turbine engine is the most costly component due to its complexity, and life requirements, given the harsh environment in which it is required to operate. Minimizing the number of stages can lead to significant savings in terms of development efforts, materials, and serviceable parts. This philosophy has led to a significant increase in the work demanded from the typical stage. In this work, a highly loaded axial turbine stage was designed for high power-output industrial applications using a comprehensive set of investigations, which included parametric studies, throughflow solutions, and 2D airfoil shapes. The design …

Effect Of Automation Management Strategies And Sensory Modalities As Applied To A Baggage Screening Task, Michelle Ann Leach

Master's Theses - Daytona Beach

Automation management strategies can assist the operator in coordinating activity in automated systems. Baggage screening is a domain in which automation and alarms can be studied in terms of signal detection theory. Baggage screening is vital to national security and should be completed in a time efficient manner without compromising accuracy. In the present study, the automation management strategies of management by consent (MBC) and management by exception (MBE) were crossed with alarm modalities of a visual (flashing) or an auditory alert which served as redundant cues in a baggage screening task. A control base line condition existed in which …

Planetary Wave Activity Observed In Polar Mesospheric Clouds, David A. Mackler

Master's Theses - Daytona Beach

In this paper, the Solar Backscatter UV spectrometer (SBUV) Polar Mesospheric Cloud (PMC) dataset was investigated for planetary wave activity following the earlier study by Merkel [2002]. To counter the sparse nature of the data, four separate methods of analysis are used in determining if planetary waves are present and how they effect PMC formation. The four methods are histograms (both in frequency of occurrence and mean albedo), periodograms using the Lomb-Scargle method, frequency-wavenumber analysis using a 2D Lomb-Scargle method from Wu et. al [1995], and a temporal (yearly) analysis of the 5, 6.5, and 10 day wave amplitudes. The …

Damage Assessment And Strength Predictions In S-Glass/Epoxy Laminates Subjected To Low Energy Impact, Tuan-Khoi Dang Nguyen

Master's Theses - Daytona Beach

Composite materials have become one of the leading materials for manufacturing in the aerospace industry today. Compared to "conventional" aerospace metals, composites generally have higher strength-to-weight and stiffness-to-weight ratios, good fatigue and corrosion resistance and reduced parts count. However, like any other material, they also have disadvantages. They are inherently brittle and are thus prone to impact damage. Low energy/velocity impact damage, in particular, can be dangerous because the damage oftentimes goes undetected and can subsequently grow under load. Also known as barely visible impact damage (BVID), this area of concentration focuses on the small-scale damage that may be very …

A Computational Study Of Thermo-Fluid Dynamics Of Pulse Detonation Engines, Alberto Davila Urresti

Master's Theses - Daytona Beach

The purpose of this thesis is to use a transient Computational Fluid Dynamics computer code written in FORTRAN 90 for full reaction kinetics, to perform an analysis of the physical processes and chemical phenomena occurring on a single cycle of an ideal Pulse Detonation Engine (PDE) using a stoichiometric mixture of H₂ and O₂. A small zone of high pressure and temperature is used to initiate the detonation wave in the PDE. A simple case with no chemical reactions and the same PDE geometry and “computational spark” is also tested. The speed of the wave relative to …

The Effect Of Level Of Automation And Operator-To-Vehicle Ratio On Operator Workload And Performance In Future Uav Systems, Ryan J. Wasson

Master's Theses - Daytona Beach

The military intends to increase the number of UAVs in service while at the same time reducing the number of operators (Dixon, Wickens & Chang; 2004). To meet this demand, many of the current UAV operator functions will need to be automated. How automation is applied to modern systems is not fixed. Levels of automation exist along a continuum from fully manual to fully automatic. Two proposed levels of automation for future UAV systems are Management by Consent (MBC), where the operator selects the task to be executed, and Management by Exception (MBE), where the computer selects the task to …

Control System Design And Simulation Of Spacecraft Formations, Daniel Dyer

Master's Theses - Daytona Beach

The objective of this thesis is to analyze an effective control scheme for a formation of spacecraft, implement that control, and provide a 3-D simulation. The thesis first summarizes the progress made in formation flight control schemes and then provides a theoretical framework for the control system design. Using established control design techniques, feedback laws are constructed to control both rotational and translational motion of a group of spacecraft. Computer simulations are carried out using Matlab to generate the ephemeris and attitude data, which are exported to Satellite Tool Kit (STK) to create animations. The process by which Matlab is …

Accuracy Of Heat-Pulse Sensors For Determining Moisture Of Capillary Mat Material Used To Support Plant Growth, Marisa Wyssling

Master's Theses - Daytona Beach

The accuracy and precision of Orbital Technologies (Orbitec, Madison, WI) Thermal and Moisture Acquisition System (TMAS) sensors were investigated for use in the WONDER space flight experiment. WONDER is studying the effect of multiple wetness level regimes and two different nutrient delivery systems (NDS) on plants grown in the microgravity of space. The following research concentrates on the porous tube NDS consisting solely of a capillary mat surrounding a bare porous tube used for water delivery. Sensors and plants will be attached to the capillary mat, which transports water by capillary action. The TMAS sensors, single probe heat-pulse moisture sensors, …