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Fully Coupled Internal Radiative Heat Transfer For The 3d Material Response Of Heat Shield, Raghava S. C. Davuluri, Rui Fu, Kaveh A. Tagavi, Alexandre Martin 2021 University of Kentucky

Fully Coupled Internal Radiative Heat Transfer For The 3d Material Response Of Heat Shield, Raghava S. C. Davuluri, Rui Fu, Kaveh A. Tagavi, Alexandre Martin

Mechanical Engineering Faculty Publications

The radiative transfer equation (RTE) is strongly coupled to the material response code KATS. A P-1 approximation model of RTE is used to account for radiation heat transfer within the material. First, the verification of the RTE model is performed by comparing the numerical and analytical solutions. Next, the coupling scheme is validated by comparing the temperature profiles of pure conduction and conduction coupled with radiative emission. The validation study is conducted on Marschall et al. cases (radiant heating, arc-jet heating, and space shuttle entry), 3D Block, 2D IsoQ sample, and Stardust Return Capsule. The validation results agree well for …


Review: Factors Affecting Composite Laminates Against Lightning Strikes, Aaryan Manoj Nair 2021 CUNY New York City College of Technology

Review: Factors Affecting Composite Laminates Against Lightning Strikes, Aaryan Manoj Nair

Publications and Research

Lightning strike protection (LSP) have recently been a newly developing field particularly with the emergence of graphene thin film integration into carbon fiber composite structures. This technology has a widespread application in airplanes, wind turbines, and other instruments which are susceptible to frequent lightning strikes. Electrical discharge of the instrument in a safe manner is vital for the safety of the passengers (in the case of flights) as well as the integrity of the aircraft structures because of their specific mechanical and structural properties, which are essential for their functioning. The purpose of the study is to fabricate graphene thin …


Fluid-Structure Interaction Of Nrel 5-Mw Wind Turbine, Mohamed Sayed Elkady Abd-Elhay 2021 The American University in Cairo AUC

Fluid-Structure Interaction Of Nrel 5-Mw Wind Turbine, Mohamed Sayed Elkady Abd-Elhay

Theses and Dissertations

Wind energy is considered one of the major sources of renewable energy. Nowadays, wind turbine blades could exceed 100 m to maximize the generated power and minimize produced energy cost. Due to the enormous size of the wind turbines, the blades are subjected to failure by aerodynamics loads or instability issues. Also, the gravitational and centrifugal loads affect the wind turbine design because of the huge mass of the blades. Accordingly, wind turbine simulation became efficient in blade design to reduce the cost of its manufacturing. The fluid-structure interaction (FSI) is considered an effective way to study the turbine's behavior …


Metallurgical And Thermal Processing Investigation Of Additively Manufactured Superalloys Jbk-75 And Nasa-Hr-1, Allyse Birken, Derek Noel 2021 California Polytechnic State University, San Luis Obispo

Metallurgical And Thermal Processing Investigation Of Additively Manufactured Superalloys Jbk-75 And Nasa-Hr-1, Allyse Birken, Derek Noel

Materials Engineering

Aerojet Rocketdyne is investigating the use of directed energy deposition (DED), an additive manufacturing process, to reduce cost and lead time for manufacturing complex rocket engine components for their RS-25 engines. JBK-75 and NASA-HR-1, two Fe-Ni-base, age-hardenable (γ′) superalloys, are used for nozzle structural jackets and hot gas manifolds. Currently, these parts are produced using traditional forging or casting methods followed by intensive machining operations. Additionally, these alloys were designed for use in the wrought condition and require a different set of post-processing heat treatments when produced using DED due to their dendritic, segregated microstructure in the as-built condition. Homogenization …


Space Suit Attachment Quick Release System, Elyse C. Gillis-Smith, Andres I. Elzaurdia, Cole H. Stanton, Michael T. Roth 2021 California Polytechnic State University, San Luis Obispo

Space Suit Attachment Quick Release System, Elyse C. Gillis-Smith, Andres I. Elzaurdia, Cole H. Stanton, Michael T. Roth

Mechanical Engineering

NASA plans to make it back to the Moon by 2024 with their Artemis Program, and stay there for a longer period of time to conduct research which will support the future of space exploration. While on the lunar surface, astronauts need to maximize their efficiency by carrying tools on their Exploration Extravehicular Mobility Unit (xEMU), and to accommodate this need, the Extravehicular Activity (EVA) Tools Team is pursuing a utility belt concept. The objective of this project is to develop a system capable of interfacing between the utility belt and any given tool, while also accommodating numerous restrictions and …


Prediction Of In-Plane Stiffnesses And Thermomechanical Stresses In Cylindrical Composite Cross-Sections, Bryson M. Chan 2021 California Polytechnic State University, San Luis Obispo

Prediction Of In-Plane Stiffnesses And Thermomechanical Stresses In Cylindrical Composite Cross-Sections, Bryson M. Chan

Master's Theses

Accurate mechanical analysis of composite structures is necessary for the prediction of laminate behavior. Cylindrical composite tubes are a mainstay in many structural applications. The fundamental design of circular composite cross-sections necessitates the development of a comprehensive composite lamination theory. A new analytical method is developed to characterize the behavior of thin-walled composite cylindrical tubes using a modified plate theory. A generated numerical solver can predict properties such as axial stiffness, bending stiffness, layer stresses, and layer strains in composite tubes subjected to combined mechanical loading and thermal effects. The model accounts for the curvature by transforming and translating the …


Inclusive Play Spaces, Carla Munemori da Rosa Borges 2021 Sheridan College

Inclusive Play Spaces, Carla Munemori Da Rosa Borges

Featured Student Work

Sheridan’s Material ConneXion Library Interior Decorating intern, Carla Munemori da Rosa Borges, researched materials suitable for a barrier-free design for children’s play areas. The role of sustainable materials in children’s play and recreation areas and the role of texture are explored. Materials from the Material ConneXion Library have been chosen and their use in inclusive play areas are analyzed for design consideration and use characteristics.


Characterizing High Entropy Alloys For Hypersonic Applications, Katherine Pettus 2021 University of Arkansas, Fayetteville

Characterizing High Entropy Alloys For Hypersonic Applications, Katherine Pettus

Mechanical Engineering Undergraduate Honors Theses

In this paper, the properties of a new and broad class of materials, high entropy alloys (HEAs), were investigated and evaluated for hypersonic applications. The plan was to identify candidate hypersonic HEAs and model the high-temperature strength using new advanced material models that account for asymmetry and anisotropy characterized with available test data. After accessing a local database of HEAs and their material properties in collaboration with Dr. Gorsse et al., it was realized the knowledge of HEAs is currently very broad but lacks depth. While hundreds of HEAs have been created and tested, none so far have both sufficient …


Louver And Effusion Cooling Heat Transfer For A Double Wall Effusion Plate With Impingement Jet Array Coolant Supply, Sneha Reddy Vanga, Phillip M. Ligrani, Joseph Knox, Federico Liberatore, Rajeshriben Patel, Ying-Hsiang Ho 2021 University of Alabama in Huntsville

Louver And Effusion Cooling Heat Transfer For A Double Wall Effusion Plate With Impingement Jet Array Coolant Supply, Sneha Reddy Vanga, Phillip M. Ligrani, Joseph Knox, Federico Liberatore, Rajeshriben Patel, Ying-Hsiang Ho

PRC-Affiliated Research

Louver slot cooling is employed, which consists of an aligned collection of film cooling holes, contained within a specially-designed device which concentrates, and directs the coolant from a slot, so that cooling air then advects as a layer downstream along the test surface. This louver-supplied coolant is then supplemented by coolant which emerges from different rows of downstream film cooling holes. Coolant for both cooling arrangements is supplied using an array of impingement jets. Experimental data are provided for a mainstream Reynolds number Rems range of 168,000–181,000. Full-coverage film cooling initial blowing ratio values are 2.5, 3.2, 4.4, and 5.2, …


Louver And Effusion Cooling Heat Transfer For A Double Wall Effusion Plate With Impingement Jet Array Coolant Supply, Sneha Reddy Vanga, Phillip M. Ligrani, Joseph Knox, Federico Liberatore, Rajeshriben Patel, Ying-Hsiang Ho 2021 University of Alabama in Huntsville

Louver And Effusion Cooling Heat Transfer For A Double Wall Effusion Plate With Impingement Jet Array Coolant Supply, Sneha Reddy Vanga, Phillip M. Ligrani, Joseph Knox, Federico Liberatore, Rajeshriben Patel, Ying-Hsiang Ho

PRC-Affiliated Research

Louver slot cooling is employed, which consists of an aligned collection of film cooling holes, contained within a specially-designed device which concentrates, and directs the coolant from a slot, so that cooling air then advects as a layer downstream along the test surface. This louver-supplied coolant is then supplemented by coolant which emerges from different rows of downstream film cooling holes. Coolant for both cooling arrangements is supplied using an array of impingement jets. Experimental data are provided for a mainstream Reynolds number Rems range of 168,000–181,000. Full-coverage film cooling initial blowing ratio values are 2.5, 3.2, 4.4, and 5.2, …


Accelerated Controller Tuning For Wind Turbines Under Multiple Hazards, Aly Mousaad Aly, Milad Rezaee 2021 Louisiana State University

Accelerated Controller Tuning For Wind Turbines Under Multiple Hazards, Aly Mousaad Aly, Milad Rezaee

Faculty Publications

During their lifecycle, wind turbines can be subjected to multiple hazard loads, such as high-intensity wind, earthquake, wave, and mechanical unbalance. Excessive vibrations, due to these loads, can have detrimental effects on energy production, structural lifecycle, and the initial cost of wind turbines. Vibration control by various means, such as passive, active, and semi-active control systems provide crucial solutions to these issues. We developed a novel control theory that enables semi-active controller tuning under the complex structural behavior and inherent system nonlinearity. The proposed theory enables the evaluation of semi-active controllers’ performance of multi-degrees-of-freedom systems, without the need for time-consuming …


Design And Analysis Of Air-Stiffened Vacuum Lighter-Than-Air Structures, Ruben Adorno-Rodriguez 2021 Air Force Institute of Technology

Design And Analysis Of Air-Stiffened Vacuum Lighter-Than-Air Structures, Ruben Adorno-Rodriguez

Theses and Dissertations

Lighter-than-air (LTA) systems have been developed for numerous applications and have taken several forms. Airships, aerostats, blimps, and balloons are all part of this family of systems, which uses Archimedes principle to achieve neutral and positive buoyancy in air by replacing an air volume with LTA gases. These lifting gases stiffen the otherwise compliant envelope structures, allowing them to sustain the pressure difference brought by the displaced air. The compliance of these structures is a byproduct of the weight requirement, materials and geometrical arrangement of which these structures are built from, typically resulting in dimensionalities that exhibit low or virtually …


Fatigue Of Two Oxide/Oxide Ceramic Matrix Composites At 1200°C In Air And In Steam. Effect Of Diamond Drilled Effusion Holes, Anthony R. Cabri 2021 Air Force Institute of Technology

Fatigue Of Two Oxide/Oxide Ceramic Matrix Composites At 1200°C In Air And In Steam. Effect Of Diamond Drilled Effusion Holes, Anthony R. Cabri

Theses and Dissertations

The tension-tension fatigue behavior of two oxide-oxide ceramic matrix composites (CMCs) was investigated at 1200°C in laboratory air and steam. Both composites consist of a porous oxide matrix reinforced with laminated, woven mullite/alumina (NextelTM720) fibers. The first composite had an alumina matrix, while the second had an alumina-mullite matrix. First, we assessed the effects of incorporating mullite into the matrix material on fatigue performance by studying the tension-tension fatigue behavior of alumina-mullite matrix CMC. Second, we evaluated the effects of effusion holes on the alumina matrix CMC's fatigue performance. Specimens containing an array of 17 effusion holes of 0.5-mm diameter …


Static Fatigue Of Hi-Nicalon™ S Ceramic Fiber Tows At 600°C In Air And Silicic Acid-Saturated Steam, Caleigh M. Nelson 2021 Air Force Institute of Technology

Static Fatigue Of Hi-Nicalon™ S Ceramic Fiber Tows At 600°C In Air And Silicic Acid-Saturated Steam, Caleigh M. Nelson

Theses and Dissertations

Ceramic matrix composites (CMCs) have the potential to be utilized in applications such as hypersonic vehicles, aircraft leading edges, hot sections of engines, and rocket nozzles. Of particular interest are advanced SiC/SiC composites that can withstand the elevated temperatures and harsh oxidizing environments while maintaining their properties and structural integrity under an applied load. Steam, a major component of combustion environment, is one such aggressive oxidizing environment. As steam passes through the SiC/SiC composite, entering the composite interior through the cracks in the SiC matrix, it becomes saturated with silicic acid, Si(OH)4. Before incorporating SiC/SiC composites in the …


Comparing Radiation Shielding Potential Of Liquid Propellants To Water For Application In Space, John Czaplewski 2021 California Polytechnic State University, San Luis Obispo

Comparing Radiation Shielding Potential Of Liquid Propellants To Water For Application In Space, John Czaplewski

Master's Theses

The radiation environment in space is a threat that engineers and astronauts need to mitigate as exploration into the solar system expands. Passive shielding involves placing as much material between critical components and the radiation environment as possible. However, with mass and size budgets, it is important to select efficient materials to provide shielding. Currently, NASA and other space agencies plan on using water as a shield against radiation since it is already necessary for human missions. Water has been tested thoroughly and has been proven to be effective. Liquid propellants are needed for every mission and also share similar …


On The Influence Of Heat Treatment On Microstructure And Mechanical Behavior Of Laser Powder Bed Fused Inconel 718, Jakob Shroder, Tatiana Mishurova, Tobias Fritsch, Itziar Serrano-Munoz, Alexander Evans, Maximilian Sprengel, Maximilian Sprengel, Manuela Klaus, Giovanni Bruno 2021 Bundesanstalt für Materialforschung und -prüfung (BAM)

On The Influence Of Heat Treatment On Microstructure And Mechanical Behavior Of Laser Powder Bed Fused Inconel 718, Jakob Shroder, Tatiana Mishurova, Tobias Fritsch, Itziar Serrano-Munoz, Alexander Evans, Maximilian Sprengel, Maximilian Sprengel, Manuela Klaus, Giovanni Bruno

PRC-Affiliated Research

A range of heat treatments have been developed for wrought Inconel 718 to obtain desired properties. For additively manufactured Inconel 718, the recently developed standard ASTM F3301 provides guidance for heat treatment of powder bed fusion specimens. Although this standard is based on standards developed for wrought Inconel 718, it does not include direct aging. Since direct aging reduces the number of processing steps, it can result in a post processing cost reduction if the desired properties are obtained. In this study, we characterized the microstructure and tensile behavior of Inconel 718 specimens produced by a laser powder bed fusion …


On The Influence Of Heat Treatment On Microstructure And Mechanical Behavior Of Laser Powder Bed Fused Inconel 718, Jakob Shroder, Tatiana Mishurova, Tobias Fritsch, Itziar Serrano-Munoz, Alexander Evans, Maximilian Sprengel, Maximilian Sprengel, Manuela Klaus, Giovanni Bruno 2021 Bundesanstalt für Materialforschung und -prüfung (BAM)

On The Influence Of Heat Treatment On Microstructure And Mechanical Behavior Of Laser Powder Bed Fused Inconel 718, Jakob Shroder, Tatiana Mishurova, Tobias Fritsch, Itziar Serrano-Munoz, Alexander Evans, Maximilian Sprengel, Maximilian Sprengel, Manuela Klaus, Giovanni Bruno

PRC-Affiliated Research

A range of heat treatments have been developed for wrought Inconel 718 to obtain desired properties. For additively manufactured Inconel 718, the recently developed standard ASTM F3301 provides guidance for heat treatment of powder bed fusion specimens. Although this standard is based on standards developed for wrought Inconel 718, it does not include direct aging. Since direct aging reduces the number of processing steps, it can result in a post processing cost reduction if the desired properties are obtained. In this study, we characterized the microstructure and tensile behavior of Inconel 718 specimens produced by a laser powder bed fusion …


Tooling Design Modeling For Composite Fuselage Of Beechcraft King Air 250 Using Catia, Miazor Fidelis Ekom 2021 Changchun University of Science and Technology

Tooling Design Modeling For Composite Fuselage Of Beechcraft King Air 250 Using Catia, Miazor Fidelis Ekom

Journal of Aviation Technology and Engineering

Aircraft’s constant operation in tough conditions necessitates the need for structural components of high strength yet low weight. Composite materials are being used as an alternative to conventional aluminum alloys because of their competitive strength-to-weight and stiffness-to-weight ratios. In this paper, the detailed design procedure of a light-aircraft composite material fuselage tooling in three dimensions is shown. In its operation, the layup tools provide a surface for the composite part which is the correct shape of the part and is stable through the cure cycle, and also providing a means of indexing the part for the next manufacturing operation. This …


Numerical Reconstruction Of Spalled Particle Trajectories In An Arc-Jet Environment, Raghava S. C. Davuluri, Sean C. C. Bailey, Kaveh A. Tagavi, Alexandre Martin 2021 University of Kentucky

Numerical Reconstruction Of Spalled Particle Trajectories In An Arc-Jet Environment, Raghava S. C. Davuluri, Sean C. C. Bailey, Kaveh A. Tagavi, Alexandre Martin

Mechanical Engineering Faculty Publications

To evaluate the effects of spallation on ablative material, it is necessary to evaluate the mass loss. To do so, a Lagrangian particle trajectory code is used to reconstruct trajectories that match the experimental data for all kinematic parameters. The results from spallation experiments conducted at the NASA HYMETS facility over a wedge sample were used. A data-driven adaptive methodology was used to adapts the ejection parameters until the numerical trajectory matches the experimental data. The preliminary reconstruction results show that the size of the particles seemed to be correlated with the location of the ejection event. The size of …


Simulation Of A Trailing Edge Flap Using A Compliant Mechanism, Sam Blackwell 2021 University of Alabama in Huntsville

Simulation Of A Trailing Edge Flap Using A Compliant Mechanism, Sam Blackwell

Summer Community of Scholars Posters (RCEU and HCR Combined Programs)

No abstract provided.


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