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Editorial, Maruthupandiyan K Dr. 2022 Associate Professor Department of Aeronautical Engineering Institute of Aeronautical Engineering Dundigal, Hyderabad

Editorial, Maruthupandiyan K Dr.

Graduate Research in Engineering and Technology (GRET)

The aeronautical engineer is responsible for using cost-effective methods to develop ways of improving fuel efficiency and flight safety. Additionally, aeronautical engineers focus on lowering the environmental impact of air travel by creating aircraft that are more environmentally friendly. In Indian scenario, the development of aeronautical related advance technologies is still to grow with the Government of India initiative for the defence product under the Atmanirbhar Bharat and hope in few years now, these advanced technologies will be booming.


The Effect Of Pre-Thermal And -Load Conditions On In-718 High Temperature Fatigue Life, Paulina De La Torre, Alberto Mello 2022 Embry-Riddle Aeronautical University

The Effect Of Pre-Thermal And -Load Conditions On In-718 High Temperature Fatigue Life, Paulina De La Torre, Alberto Mello

Publications

Ni-based superalloys are largely used in the aerospace industry as critical components for turbine engines due to their excellent mechanical properties and fatigue resistance at high temperatures. A hypothesis to explain this atypical characteristic among metals is the presence of a cross-slip mechanism. Previous work on the role of thermal activation on cubic slip has shown strain accommodation in two sets of slip planes, which resembled the activation of {100} cubic slip systems along of the octahedral slip planes {111} in Ni-based superalloys under high strain and temperature, exhibiting a more homogeneous strain distribution and less strain localization. Following those …


Influence Of Cold Expansion And Aggressive Environment On Crack Growth In Aa2024-T3, Ken Shishino, Christopher Leirer, Alberto Mello 2022 Embry-Riddle Aeronautical University

Influence Of Cold Expansion And Aggressive Environment On Crack Growth In Aa2024-T3, Ken Shishino, Christopher Leirer, Alberto Mello

Publications

This research aims to establish the effect of hole cold expansion on fatigue life of pre-cracked material under aggressive environment. A relationship between crack propagation and secondary crack initiation was established for AA2024-T3 cold worked holes subjected to cyclic loads to determine the impact on fatigue life of joints in presence of saline solution. Galvanic corrosion of a steel fastener/aluminum plate assembly was investigated assuming the presence of cracks in the aluminum plates, whose growth will be monitored in-situ with a digital microscope throughout the fatigue process. The cold expansion treatment improved the fatigue life fourfold under a corrosive environment, …


Effects Of A Nitrogen And Hydrogen Build Atmosphere On The Properties Of Additively Manufactured Tungsten, Dana C. Madsen 2022 Air Force Institute of Technology

Effects Of A Nitrogen And Hydrogen Build Atmosphere On The Properties Of Additively Manufactured Tungsten, Dana C. Madsen

Theses and Dissertations

Additively manufactured tungsten was printed in pure nitrogen, nitrogen-2.5% hydrogen, and nitrogen-5% hydrogen atmospheres as part of a 2^3 full factorial designed experiment and subjected to room temperature and high-temperature three-point-bend testing, chemical analysis, hardness testing, and microstructural imaging techniques. The pure nitrogen specimens exhibited the highest strength and ductility at both high temperature and room temperature. Chemical analysis showed a 2-8x reduction in compositional oxygen relative to unprocessed powder. Hardness values for all samples was between 306.8 and 361.5 HV1. It is proposed that adding hydrogen into the build atmosphere reduced the available energy density for tungsten melting by …


Investigation Of Additively Manufactured Molybdenum-Tungsten-Rhenium Alloys, Randolph T. Abaya 2022 Air Force Institute of Technology

Investigation Of Additively Manufactured Molybdenum-Tungsten-Rhenium Alloys, Randolph T. Abaya

Theses and Dissertations

The process of creating metal components through additive manufacturing is changing the way different industries can avoid the shortcomings of traditional metal production. Metals such as tungsten, molybdenum, and rhenium have many advantages for different applications, especially when alloyed together. In this study, an additively manufactured alloy containing 70% molybdenum, 25% tungsten, and 5% rhenium (70Mo-25W-5Re) is tested for its strength, ductility, hardness, and porosity. The 70Mo-25W-5Re alloy is printed through Laser Powder Bed Fusion (LPBF) under different conditions such as printing speed and printing atmosphere. Additionally, the effects of post printing heat treatment are conducted to understand the advantages …


Thermal Relaxation Of Shot Peen Induced Residual Stresses In A Nickel-Base Superalloy, Bryce E. Van Velson 2022 Air Force Institute of Technology

Thermal Relaxation Of Shot Peen Induced Residual Stresses In A Nickel-Base Superalloy, Bryce E. Van Velson

Theses and Dissertations

Shot peening induces compressive residual stresses in components that positively influence fatigue life. Thermal and mechanical loading causes those residual stresses to relax. The hole drilling method and xray diffraction is used to measure the thermal relaxation of residual stresses in the nickel-base superalloy ME3.


Aeroelastic Analysis Of Small-Scale Aircraft, Kent Roberts 2022 California Polytechnic State University, San Luis Obispo

Aeroelastic Analysis Of Small-Scale Aircraft, Kent Roberts

Master's Theses

The structural design of flight vehicles is a balancing act between maximizing loading capability while minimizing weight. An engineer must consider not only the classical static structural yielding failure of a vehicle, but a variety of ways in which structural deformations can in turn, affect the loading conditions driving those deformations. Lift redistribution, divergence, and flutter are exactly such dynamic aeroelastic phenomena that must be properly characterized during the design of a vehicle; to do otherwise is to risk catastrophe. Relevant within the university context is the design of small-scale aircraft for student projects and of particular consideration, the DBF …


Jcati Carbon Fiber Recycler: Oven Enclosure, Margarita Romero 2022 Central Washington University

Jcati Carbon Fiber Recycler: Oven Enclosure, Margarita Romero

All Undergraduate Projects

Central Washington University partners with Boeing and is funded by the Joint Center of Aerospace Technology Innovation (JCATI) to develop a mechanism that takes carbon fiber wing trimmings from Boeing that are resin coated and recycles carbon fiber. This is done by crushing the wing trimmings and then putting it into a 500°C oven to melt off the resin. This project focuses on the enclosure for the oven and making sure precautions are met such as having the outside surface be less than 45c through heat transfer analysis, argon fills enclosure in 13 minutes through fluid dynamics analysis, and 99% …


Carbon Fiber Recycling: Delamination System, Aaron Eastman 2022 Central Washington University

Carbon Fiber Recycling: Delamination System, Aaron Eastman

All Undergraduate Projects

The production of composite wings at Boeing causes carbon fiber waste and CWU Mechanical Engineering Technology students have been tasked in designing a carbon fiber recycling system. This project was brought forth and funded by the Joint Center for Aerospace Technology Innovation (JCATI). There are three subsystems that make up the carbon fiber recycling system, the delamination system, shredding system, and the oven. The purpose of this project was to increase the efficiency and effectiveness of the delamination system of the carbon fiber recycling system. The old system reached approximately 30-40 percent delamination with one pass through the system, and …


Model-Based Systems Engineering For A Small-Lift Launch Facility, Walter McGee Taraila, Sharanabasaweshwara Asundi 2022 Old Dominion University

Model-Based Systems Engineering For A Small-Lift Launch Facility, Walter Mcgee Taraila, Sharanabasaweshwara Asundi

Mechanical & Aerospace Engineering Faculty Publications

A study of model‐based systems engineering (MBSE) applied to a small‐lift launch facility is presented. The research uses Systems Modeling Language (SysML) products and functional diagrams to document the ground systems on a launch pad servicing a small class payload (0–2 tons). With the projected growth in launch cadence of small‐lift rockets in the coming decade, there is a need to design increasingly complex launch systems with greater efficiency. The potential improvements in project communication, quality, and productivity are explored by developing a model following the ISO/IEC 15288 technical process framework and the International Council on Systems Engineering (INCOSE) Object‐Oriented …


Kentucky Re-Entry Universal Payload System (Krups): Hypersonic Re-Entry Flight, John Daniel Schmidt 2022 University of Kentucky

Kentucky Re-Entry Universal Payload System (Krups): Hypersonic Re-Entry Flight, John Daniel Schmidt

Theses and Dissertations--Mechanical Engineering

The Kentucky Re-entry Universal Payload System (KRUPS) is a small capsule designed as a technology testbed for re-entry experiments. For its first incarnation, KRUPS has been designed to test Thermal Protection Systems (TPS) and instruments in re-entry flights. Because of the unique environment a vehicle undergoes during re-entry, there is a high-demand for experimental data from re-entry experiments. KRUPS has been developed at the University of Kentucky (UK) over the past seven years to meet this demand. After completing sub-orbital campaigns, the first KRUPS hypersonic re-entry mission was attempted. The mission involved building three 11-inch diameter capsules each outfitted with …


Digital Image Correlation System Design, Verification And Analysis, Tyler Kraft, Matthew J. Riczo, Andrew Chong 2022 The University of Akron

Digital Image Correlation System Design, Verification And Analysis, Tyler Kraft, Matthew J. Riczo, Andrew Chong

Williams Honors College, Honors Research Projects

Two dimensional digital image correlation provides an accurate and effective way to capture strain data on test sections with unusual or oblique geometries. The system requires a camera to record video footage, alignment fixtures and software to convert the footage into strain values. The system works by capturing the video footage of a specific portion of the specimen and comparing the movement of selected pixels. This is all done in the software GOM Correlate and Tracker. This test document outlines the setup, procedure, and validation steps to fulfill this goal. The setup involves a camera, tripod, blue lighting, and laser …


Autonomous Payload Design With Systems Engineering, Michael Downs, Christopher James Liebhart 2nd 2022 The University of Akron

Autonomous Payload Design With Systems Engineering, Michael Downs, Christopher James Liebhart 2nd

Williams Honors College, Honors Research Projects

The design will be an autonomous payload consisting of auto deployment of a drone running an autonomous mission of mapping the terrain around a grounded rocket. The project is part of the Akronauts payload project for the 2022 Spaceport competition. It will include the development of a ground station for monitoring and controlling the drone and the transfer of live data to the station and a computer on board the rocket. The project will aim to use system engineering techniques to accomplish this in the hope of providing documentation and thus insight into the best way to develop a multi-disciplinary …


The Effects Of Geometry And Architecture Of Polymer Matrix Composites On Acoustic Emissions, John J. Bush, Alex D. Swartzentruber, Lukas B. Thompson, Sarah R. Pratt, Chris J. Kuhn 2022 The University of Akron

The Effects Of Geometry And Architecture Of Polymer Matrix Composites On Acoustic Emissions, John J. Bush, Alex D. Swartzentruber, Lukas B. Thompson, Sarah R. Pratt, Chris J. Kuhn

Williams Honors College, Honors Research Projects

The purpose of this project is to study how the variance of the geometry and architecture of polymer matrix composites (PMCs) affect the acoustic emissions measured whilst said structures are subjected to tensile stress. In these tests, a method called Modal AE will be utilized. In Modal AE, some relationships between sources and waves in various materials and geometries are presented in other papers/research. This study will focus on how different thickness and different makeup/ply patterns affect the acoustic emission tests. Some research has been completed and shown how energy attenuation affects the frequency content on PMCs similar to the …


The Design Of The Payload System Of An Aircraft, Ryan Cooper 2022 The University of Akron

The Design Of The Payload System Of An Aircraft, Ryan Cooper

Williams Honors College, Honors Research Projects

The project group will design and build a system to unload packages for the Zips Aero Design Team's aircraft for the 2021-22 competition year.


Fuel System To Envelope Interface, James Campbell 2022 The University of Akron

Fuel System To Envelope Interface, James Campbell

Williams Honors College, Honors Research Projects

*NOTE THIS PROJECT IS CONFIDENTIAL*

In this project, I will investigate solutions to interfacing a fuel system with a fabric skin section


Design, Development, And Testing Of Near-Optimal Satellite Attitude Control Strategies, Giovanni Lavezzi 2022 South Dakota State University

Design, Development, And Testing Of Near-Optimal Satellite Attitude Control Strategies, Giovanni Lavezzi

Electronic Theses and Dissertations

Advances in space technology and interest toward remote sensing mission have grown in the recent years, requiring the attitude control subsystems of observation satellites to increase their performances in terms of pointing accuracy and on-board implementability. Moreover, an increased interest in small satellite missions and the recent technological developments related to the CubeSats standard have drastically reduced the cost of producing and flying a satellite mission. In this context, the proposed research aims to improve the state of the art for satellite attitude control methodologies by proposing a near-optimal attitude control strategy, simulated in a high-fidelity environment. Two strategies are …


Microscale Transverse Compression Modeling: A Comparative Study Of The Analytical Mac/Gmc Methods To Experimental Results, Emily Zeitunian 2022 Michigan Technological University

Microscale Transverse Compression Modeling: A Comparative Study Of The Analytical Mac/Gmc Methods To Experimental Results, Emily Zeitunian

Dissertations, Master's Theses and Master's Reports

Composite materials require a multi-scale approach to fully understand its behavior. At the micro level, material behavior analysis is conducted most often using numerical or analytical approaches. These models, however, require validation from experimental data to ensure material predictions are accurate. This study compares a semi-analytical micromechanical analysis tool, MAC/GMC, to experimental results of in-situ microscale transverse compression testing conducted at AFRL facilities. Effective properties, stress-strain curves, stress and strain fields, and damage predictions are compared with experimental outputs. Both generalized method of cells (GMC) and high-fidelity generalized method of cells (HFGMC) theories implemented within MAC/GMC show results that agree …


Experimental Analysis Of Double Box Wing Uav., Sai Adithya Vanga, Moulshree Srivastava, Y. D. Dwivedi 2021 Institute of Aeronautical Engineering, Dundigal, Hyderabad

Experimental Analysis Of Double Box Wing Uav., Sai Adithya Vanga, Moulshree Srivastava, Y. D. Dwivedi

Graduate Research in Engineering and Technology (GRET)

ABSTRACT

In an attempt to reduce the induced drag on a wing, Prandtl found that induced drag reduced significantly by highly increasing the number of vertically offset wings. The same result could be obtained by joining the wingtips of two vertically offset wings. This helped increase payload capacity and also reduced fuel consumption and emissions. Such a wing configuration came to be known as Prandtl’s box wing. In this work, the design and analysis of a box wing aircraft model has been carried out. The preliminary analysis is performed using XFLR5, and the computational analysis is done with the help …


Editorial, Y D Dwivedi 2021 Institute of Aeronautical Engineering

Editorial, Y D Dwivedi

Graduate Research in Engineering and Technology (GRET)

The special issue “Emerging Aerospace Technologies in Aerodynamics, Propulsion, and Materials” is published which covers the aerospace domain covering aerodynamics, propulsion, and materials used for aeronautical and aerospace domains. In this issue, the authors have focused on the articles related to experimental and computational work related to aircraft performance, aircraft stability and control, materials, and some other important areas. Most of the papers are based on Project Based Learning which is one of the research-oriented teaching-learning processes recently introduced in National Education Policy 2020 by the Government of India.


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