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Aerospace Engineering Commons

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Mesh Tailoring For Strongly Coupled Computation Of Ablative Material In Nonequilibrium Hypersonic Flow, Alexandre Martin, Iain D. Boyd 2010 University of Michigan - Ann Arbor

Mesh Tailoring For Strongly Coupled Computation Of Ablative Material In Nonequilibrium Hypersonic Flow, Alexandre Martin, Iain D. Boyd

Alexandre Martin

A one-dimensional material response implicit solver with surface ablation and pyrolysis is strongly coupled to LeMANS, a CFD code for the simulation of weakly ionized hypersonic flows in thermo-chemical non-equilibrium. Using blowing wall boundary conditions and a moving mesh algorithm, the results of a strongly coupled solution of a sample re-entry problem are presented. Because of the requirement of a coupling scheme, an Arbitrary Lagrangian-Eulerian (ALE) approach is used to compute the flux, allowing the mesh to move as the surface ablates. However, as the shape of the vehicle changes, the shock location and geometry are also modified. Using the ...


Delamination Of Sandwich Composites, Richard Anthony Davis 2010 California Polytechnic State University - San Luis Obispo

Delamination Of Sandwich Composites, Richard Anthony Davis

Aerospace Engineering

The use of shear keys to help stop or inhibit the face-sheet core delamination of sandwich composite beams under monotonic loading was analyzed in Cal Poly’s structural design lab. The composite beams were treated with the same boundary conditions as the ASTM D5528 double cantilever beam bending in which both faces of the beam remain free; one of the faces would have a debonded side and the other would not. An aluminum tab is attached to the top of the specimens and the load is applied there. Each specimen has piezoelectric sensors that are utilized in the detection of ...


Team Volocity, Beth Clement, William Schuman 2010 University of Tennessee - Knoxville

Team Volocity, Beth Clement, William Schuman

Chancellor’s Honors Program Projects

No abstract provided.


An Empirical Model Of Thermal Updrafts Using Data Obtained From A Manned Glider, Christopher E. Childress 2010 University of Tennessee - Knoxville

An Empirical Model Of Thermal Updrafts Using Data Obtained From A Manned Glider, Christopher E. Childress

Masters Theses

Various methods have been used, including airborne radars, LIDAR, observation of flying birds, towers, tethered balloons, and aircraft to gain both a qualitative and quantitative representation of how heat and moisture are transported to higher altitudes and grow the boundary or mixing layer by thermal updrafts. This paper builds upon that research using an instrumented glider to determine the structure and build a mathematical model of thermals in a desert environment. During these flights, it was discovered that the traditional view of a thermal as a singular rising plume of air did not sufficiently explain what was being observed, but ...


Guidance And Navigation Linear Covariance Analysis For Lunar Powered Descent, Travis J. Moesser 2010 Utah State University

Guidance And Navigation Linear Covariance Analysis For Lunar Powered Descent, Travis J. Moesser

All Graduate Theses and Dissertations

A linear covariance analysis is conducted to assess closed-loop guidance, navigation, and control system (GN&C) performance of the Altair vehicle during lunar powered descent. Guidance algorithms designed for lunar landing are presented and incorporated into the closed-loop covariance equations. Navigation-based event triggering is also included in the covariance formulation to trigger maneuvers and control dispersions. Several navigation and guidance trade studies are presented demonstrating the influence of triggering and guidance and study parameters on the vehicle GN&C performance.


A Novel Telescopic Boom Deployment System For Use In Upper Atmosphere Research, Mark Wylie, Paul Duffy, Dinesh Vather, Johnalan Keegan, Stephen Curran 2010 Dublin Institute of Technology

A Novel Telescopic Boom Deployment System For Use In Upper Atmosphere Research, Mark Wylie, Paul Duffy, Dinesh Vather, Johnalan Keegan, Stephen Curran

Conference Papers

Typical measurement probe deployment systems on sounding rockets employ hinged booms which extend the probes away from the rocket. This configuration often has a significant mass and may require a considerable amount of the rocket’s valuable payload volume. In an effort to reduce both mass and volume, the DIT Space Research Group have designed a light weight carbon fibre telescopic boom system, compatible with measurement probes commonly used in upper atmosphere research. Our design has been selected to be tested on a suborbital space flight onboard the REXUS 9 sounding rocket in March 2011. The purpose of this test ...


Capstone Design: Energy Efficient Windows Triple Pane Window Analysis, Michael S. Kee, Drew Ryan Hughes, Amanda Michele Lee, Michael McMillan, Jake Eric Plewa 2010 University of Tennessee - Knoxville

Capstone Design: Energy Efficient Windows Triple Pane Window Analysis, Michael S. Kee, Drew Ryan Hughes, Amanda Michele Lee, Michael Mcmillan, Jake Eric Plewa

Chancellor’s Honors Program Projects

No abstract provided.


Theoretical Models For Wall Injected Duct Flows, Tony Saad 2010 University of Tennessee Space Institute

Theoretical Models For Wall Injected Duct Flows, Tony Saad

Doctoral Dissertations

This dissertation is concerned with the mathematical modeling of the flow in a porous cylinder with a focus on applications to solid rocket motors. After discussing the historical development and major contributions to the understanding of wall injected flows, we present an inviscid rotational model for solid and hybrid rockets with arbitrary headwall injection. Then, we address the problem of pressure integration and find that for a given divergence free velocity field, unless the vorticity transport equation is identically satisfied, one cannot find an analytic expression for the pressure by direct integration of the Navier-Stokes equations. This is followed by ...


Analysis Of Square-Root Kalman Filters For Angles-Only Orbital Navigation And The Effects Of Sensor Accuracy On State Observability, Jason Knudsen Schmidt 2010 Utah State University

Analysis Of Square-Root Kalman Filters For Angles-Only Orbital Navigation And The Effects Of Sensor Accuracy On State Observability, Jason Knudsen Schmidt

All Graduate Theses and Dissertations

Angles-only navigation is simple, robust, and well proven in many applications. However, it is sometimes ill-conditioned for orbital rendezvous and proximity operations because, without a direct range measurement, the distance to approaching satellites must be estimated by firing thrusters and observing the change in the target's bearing. Nevertheless, the simplicity of angles-only navigation gives it great appeal. The viability of this technique for relative navigation is examined by building a high-fidelity simulation and evaluating the sensitivity of the system to sensor errors. The relative performances of square-root filtering methods, including Potter, Carlson, and UD factorization filters, are compared to ...


An Exploration Of Formal Methods And Tools Applied To A Small Satellite Software System, Russell J. Grover 2010 Utah State University

An Exploration Of Formal Methods And Tools Applied To A Small Satellite Software System, Russell J. Grover

All Graduate Theses and Dissertations

Formal system modeling has been a topic of interest in the research community for many years. Modeling a system helps engineers understand it better and enables them to check different aspects of it to ensure that there is no undesired or unexpected behavior and that it does what it was designed to do. This thesis takes two existing tools that were created to aid in the designing of spacecraft systems and creates a layer to connect them together and allow them to be used jointly. The first tool is a library of formal descriptions used to specify spacecraft behavior in ...


Modeling The Momentum And Mass Transfer Within A Micro-Scale Polymer Electrolyte Membrane Fuel Cell For Flows Within The Slip Flow Regime, Sean Tamarun Goudy 2010 Western Michigan University

Modeling The Momentum And Mass Transfer Within A Micro-Scale Polymer Electrolyte Membrane Fuel Cell For Flows Within The Slip Flow Regime, Sean Tamarun Goudy

Dissertations

Polymer Electrolyte Membrane (PEM) fuel cell systems are heterogeneous catalytic systems. Although there are many computational models that describe the behavior of PEM fuel cells, few simulate the catalyst surface concentration of reactant gases at the catalyst layer-membrane layer inteface. Most PEM fuel cell models make no distinction between the bulk concentration of reactants and the catalyst surface concentration of reactants. It is the surface concentration that is key when studying PEM fuel cell systems: the reactions occur at the surface of the catalyst.

In addition, few model the dynamics within the non-continuum flow region near the solid surfaces of ...


Women In The Aviation Industry, Maureen N. Mutisya 2010 Liberty University

Women In The Aviation Industry, Maureen N. Mutisya

Senior Honors Theses

The Aviation industry has developed extensively since its establishment by the Wright Brothers in 1903. Over time, the highly male-dominated industry experienced significant changes to incorporate female aviators. Determined women initiated this process through participating in the aircraft engineering sector and pursuing careers as pilots. However, these women faced various challenges, which resulted in setbacks to their effective growth in the industry. In fact, vital issues encountered in the past are still present and often overlooked in today’s aviation industry. Therefore, identifying these problems and proposing solutions with effective corrective measures is necessary to increase and motivate female pilots ...


Determination Of Material Emission Signatures By Ptr-Ms And Their Correlations With Odor Assessments By Human Subjects, Kwanghoon Han 2010 BEESL Lab., Syracuse University

Determination Of Material Emission Signatures By Ptr-Ms And Their Correlations With Odor Assessments By Human Subjects, Kwanghoon Han

Kwanghoon Han

The objectives of this study were to determine volatile organic compound (VOC) emission signatures of nine typical building materials by using proton transfer reaction-mass spectrometry (PTR-MS) and to explore the correlation between the PTR-MS measurements and the measurements of acceptability by human subjects. VOC emissions from each material were measured in a 50-l small-scale chamber. Chamber air was sampled by PTR-MS to determine emission signatures. Sorbent tube sampling and TD-GC/MS analysis were also performed to identify the major VOCs emitted and to compare the resulting data with the PTR-MS emission signatures. The data on the acceptability of air quality ...


Numerical Simulation Of A Liquid Jet Atomization And Break-Up Using Ansys-Cfx 12.0, Yash Akhil Bhatt 2010 Embry-Riddle Aeronautical University - Daytona Beach

Numerical Simulation Of A Liquid Jet Atomization And Break-Up Using Ansys-Cfx 12.0, Yash Akhil Bhatt

Theses - Daytona Beach

Break-up and atomization characteristics of JetA liquid fuel were investigated numerically. The results have been compared to various experimental results to evaluate the accuracy of the numerical model. The CFD code ANSYS-CFX 12.0 was used to carry out the steady state analysis at different time scales. A comparison between the atomization characteristics of a pressure jet atomizer and an air-blast atomizer is shown. By employing a Lagrangian particle tracking method to track the path of the liquid particles, the liquid jet/spray phenomena was studied in light of low and high back pressure environments. The 'BLOB' primary atomization model ...


Effect Of Time Pressure And Task Uncertainty On Human Operator Performance And Workload For Autonomous Aerial Vehicle Missions, Trevor Peterson 2010 Embry-Riddle Aeronautical University - Daytona Beach

Effect Of Time Pressure And Task Uncertainty On Human Operator Performance And Workload For Autonomous Aerial Vehicle Missions, Trevor Peterson

Theses - Daytona Beach

Unmanned aircraft systems (UAS) are being utilized at an increasing rate for a number of military applications. The potential for their use in the national airspace is also of interest to the Federal Aviation Administration, but there are some concerns about the safety of flying unmanned aircraft. The role of a UAS operator differs from that of a pilot in a manned aircraft, and this new role creates a need for a shift in interface and task design in order to take advantage of the full potential of these systems. This study examined the effect of time pressure and task ...


Neural Network Fatigue Life Prediction In Notched Aluminum Specimens From Acoustic Emission Data, Muhammed Arif Okur 2010 Embry-Riddle Aeronautical University - Daytona Beach

Neural Network Fatigue Life Prediction In Notched Aluminum Specimens From Acoustic Emission Data, Muhammed Arif Okur

Theses - Daytona Beach

This purpose of this research was to identify fatigue crack growth and predict failure for 7075-T6 aluminum notched bars under uniaxial tensile loading using acoustic emission (AE) data. The experiments performed in this study extend the results obtained by previous researchers who used maximum cyclic loads of 4,000, 3,000, and 2,000 pounds at a stress ratio of R = 0.0 and a frequency of 1 Hz to perform the fatigue tests. For this research the cyclic load remained at 2,000 pounds, but an additional ten specimens were tested in order to increase the amount of AE ...


Flightlines, Vol. 17, No. 2, Jeffrey A. Johnson 2010 St. Cloud State University

Flightlines, Vol. 17, No. 2, Jeffrey A. Johnson

Flightlines Newsletter

No abstract provided.


Acoustic Emission Fatigue Crack Monitoring Of A Simulated Aircraft Fuselage Structure, Jeremy James Lucas 2010 Embry-Riddle Aeronautical University - Daytona Beach

Acoustic Emission Fatigue Crack Monitoring Of A Simulated Aircraft Fuselage Structure, Jeremy James Lucas

Dissertations and Theses

The purpose of this research was to replicate the fatigue cracking that occurs in aircraft placed under loads from cyclical compression and decompression. As a fatigue crack grows, it releases energy in the form of acoustic emissions. These emissions are transmitted through the structure in waves, which can be recorded using acoustic emission (AE) transducers. This research employed a pressure vessel constructed out of aluminum and placed under cyclical loads at 1 Hz in order to simulate the loads placed on an aircraft fuselage in flight. The AE signals were recorded by four resonant AE transducers. These were placed on ...


Experimental Development Of Compressor And Turbine Performance Maps For Turbomachinery, Michael W. Green 2010 California Polytechnic State University - San Luis Obispo

Experimental Development Of Compressor And Turbine Performance Maps For Turbomachinery, Michael W. Green

Aerospace Engineering

Turbomachinery performance maps are used to reveal the on and off design performance of compressors and turbines. These maps plot the component’s pressure ratio versus the corrected flow rate for multiple engine rotor speeds. In this experiment, a Boeing T50-BO-8A converted turbojet engine was operated at a wide variety of rotor speeds with orifice plates of different sizes to vary the flow rate. The corrected flow rate through the turbojet ranged from 1.32 to 2.55 lb/s. The pressure ratios for the compressor and turbine ranged from 2.0 to 4.3 and from 1.7 to ...


Section Abstracts: Aeronautical And Aerospace Sciences, 2010 Old Dominion University

Section Abstracts: Aeronautical And Aerospace Sciences

Virginia Journal of Science

Abstracts of the Aeronautical and Aerospace Science Section for the 88th Annual Meeting of the Virginia Academy of Science, May 20-21, 2010, James Madison University, Harrisonburg, VA.


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