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Aerodynamics and Fluid Mechanics Commons

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All Articles in Aerodynamics and Fluid Mechanics

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Topologically Optimized Electrodes For Electroosmotic Actuation, Jianwen Sun, Jianyu Zhang, Ce Guan, Teng Zhou, Shizhi Qian, Yongbo Deng 2023 Old Dominion University

Topologically Optimized Electrodes For Electroosmotic Actuation, Jianwen Sun, Jianyu Zhang, Ce Guan, Teng Zhou, Shizhi Qian, Yongbo Deng

Mechanical & Aerospace Engineering Faculty Publications

Electroosmosis is one of the most used actuation mechanisms for the microfluidics in the current active lab-on-chip devices. It is generated on the induced charged microchannel walls in contact with an electrolyte solution. Electrode distribution plays the key role on providing the external electric field for electroosmosis, and determines the performance of electroosmotic microfluidics. Therefore, this paper proposes a topology optimization approach for the electrodes of electroosmotic microfluidics, where the electrode layout on the microchannel wall can be determined to achieve designer desired microfluidic performance. This topology optimization is carried out by implementing the interpolation of electric insulation and electric ...


Commercial Airliner Winglet Design Optimization – A Case Study, Anthony Gutierrez 2022 Kennesaw State University

Commercial Airliner Winglet Design Optimization – A Case Study, Anthony Gutierrez

Symposium of Student Scholars

The objective of this research is to determine the effect on aerodynamic performance due to changes of winglets design variables found of the Boeing 737-700 aircraft. The various winglet types studied in this research include the blended, canted, wingtip fence and split scimitar. The variables include height, sweep angle, taper ratio, and the inclination angle. These variables are altered in 5% increments from -15% to +15% of their original baseline values. Each altered winglet design only changes one variable at a time while keeping all other variables constant. The altered models are compared to the original by finding the aerodynamic ...


Development Of A Trailing Edge Flap Using A Compliant Mechanism, Matthew Maybee 2022 University of Alabama in Huntsville

Development Of A Trailing Edge Flap Using A Compliant Mechanism, Matthew Maybee

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

No abstract provided.


Low-Reynolds-Number Locomotion Via Reinforcement Learning, Yuexin Liu 2022 New Jersey Institute of Technology

Low-Reynolds-Number Locomotion Via Reinforcement Learning, Yuexin Liu

Dissertations

This dissertation summarizes computational results from applying reinforcement learning and deep neural network to the designs of artificial microswimmers in the inertialess regime, where the viscous dissipation in the surrounding fluid environment dominates and the swimmer’s inertia is completely negligible. In particular, works in this dissertation consist of four interrelated studies of the design of microswimmers for different tasks: (1) a one-dimensional microswimmer in free-space that moves towards the target via translation, (2) a one-dimensional microswimmer in a periodic domain that rotates to reach the target, (3) a two-dimensional microswimmer that switches gaits to navigate to the designated targets ...


Modeling And Structural Analysis Of Morphing Wing In Uavs, Gunda Shiva krishna Prof. 2022 Assistant professor Department of aerospace engineering Amity school of engineering and technology, Mumbai & amity university, Maharashtra

Modeling And Structural Analysis Of Morphing Wing In Uavs, Gunda Shiva Krishna Prof.

Graduate Research in Engineering and Technology (GRET)

Morphing structure enables an aircraft to alter its configuration in maneuver to operate effectively in a given flight reign. A continuous wing is utilized to reduce drag as the wing deformation is approximated more closely. With such wing morphing of skin supported with underlying truss structure, they are able to control the unsteady aerodynamic forces. This project seeks to expand and unravel the capability of an aircraft through the application of a reconfigurable “morphing” wing. In this project, the structural model of the morphing wing consists of primarily wing components designed in solid works. Structural analysis of wing components has ...


Comprehensive Review Of Heat Transfer Correlations Of Supercritical Co2 In Straight Tubes Near The Critical Point: A Historical Perspective, Douglas C. Lopes, Yang Chao, Vinusha Dasarla, Neil P. Sullivan, Mark Ricklick, Sandra Boetcher, Douglas Cabrera Lopes 2022 Embry-Riddle Aeronautical University

Comprehensive Review Of Heat Transfer Correlations Of Supercritical Co2 In Straight Tubes Near The Critical Point: A Historical Perspective, Douglas C. Lopes, Yang Chao, Vinusha Dasarla, Neil P. Sullivan, Mark Ricklick, Sandra Boetcher, Douglas Cabrera Lopes

Publications

An exhaustive review was undertaken to assemble all available correlations for supercritical CO2 in straight, round tubes of any orientation with special attention paid to how the wildly varying fluid properties near the critical point are handled. The assemblage of correlations, and subsequent discussion, is presented from a historical perspective, starting from pioneering work on the topic in the 1950s to the modern day. Despite the growing sophistication of sCO2 heat transfer correlations, modern correlations are still only generally applicable over a relatively small range of operating conditions, and there has not been a substantial increase in predictive capabilities. Recently ...


Application Of Tensile Testing Machine For Measurement Of Skin Friction Coefficient, Jeremy Silver-Mahr 2022 Western University

Application Of Tensile Testing Machine For Measurement Of Skin Friction Coefficient, Jeremy Silver-Mahr

Undergraduate Student Research Internships Conference

Traditionally fluid drag associated with skin friction is conducted by the measurement of constrained fluid flow across a textured surface. This works well for easy-to-handle fluids such as water and oil, however it is less feasible for fluids such as liquid metals. A device that measures the drag force on a surface through a static fluid would allow for different fluid types and sample geometries to be tested. A fish scale pattern consisted of overlapping repeating circular planes 3mm in diameter angled to achieve 0.14mm of depth was embossed onto a PMMA sheet. A control sample of smooth PMMA ...


Experiments To Mitigate Flow Recirculation In A Closed Anechoic Chamber Using Mesh Screens As Turbulence Suppressors, Tori Kay Wolverton 2022 Mississippi State University

Experiments To Mitigate Flow Recirculation In A Closed Anechoic Chamber Using Mesh Screens As Turbulence Suppressors, Tori Kay Wolverton

Theses and Dissertations

The desire to gather acoustic data of a propeller in simulated hover without environmental effects is met with the challenge of recirculating flow in a closed anechoic chamber. Flow recirculation in an anechoic chamber is not ideal because the effects of it being ingested by the rotor cause unsteady loadings on the propeller. This unsteady loading causes vortex noise from the turbulence introduced by the recirculation of the flow. The aim is to study the acoustic signature of a propeller separate from external factors and engine noise. Two different propellers with three different screen combinations were tested in a closed ...


Predictive Capabilities Of Laminar-Turbulent Transition Models For Aerodynamics Applications, Jared Alexander Carnes 2022 University of Tennessee, Knoxville

Predictive Capabilities Of Laminar-Turbulent Transition Models For Aerodynamics Applications, Jared Alexander Carnes

Doctoral Dissertations

Laminar-turbulent boundary-layer transition has a demonstrable impact on the performance of aerospace vehicles. The ability to accurately predict transition is integral to properly capturing relevant flow physics. Traditionally, computational fluid dynamics simulations are performed fully turbulent, meaning that laminar flow is neglected. This, however, can result in errant predictions of vehicle performance as quantities such as skin-friction drag may be overpredicted. Resultingly, development of Reynolds-averaged Navier-Stokes transition models has seen significant attention over the last decades in order to model transition and realize the performance improvements of laminar flow.

In this work, the behaviors of several different transition-prediction methods are ...


Studies Of Multiphase Distribution And Flow In Bubble/ Slurry Bubble Columns With /Without Internals And Advanced Sustainable Construction Materials Using Sophisticated Measurement Techniques, Omar Farid 2022 Missouri University of Science and Technology

Studies Of Multiphase Distribution And Flow In Bubble/ Slurry Bubble Columns With /Without Internals And Advanced Sustainable Construction Materials Using Sophisticated Measurement Techniques, Omar Farid

Doctoral Dissertations

"Bubble/slurry bubble columns have been widely studied and employed as multiphase flow reactors with and without vertical heat-exchanging tubes. In order to understand more deeply the effect of the dense internals on the hydrodynamics of bubble/slurry bubble column, systematic experiments were performed to visualize and quantify using the radioactive particle tracking (RPT) technique. A new methodology for implementing the radioactive particle tracking (RPT) technique has been developed to investigate the effect of the dense internals on the hydrodynamics of the bubble/slurry column reactor. Monte Carlo N-Particle (MCNP) simulation has been implemented to simulate the system to generate ...


Controller Platform Design And Demonstration For An Electric Aircraft Propulsion Driv, Rosten Sweeting 2022 University of Arkansas, Fayetteville

Controller Platform Design And Demonstration For An Electric Aircraft Propulsion Driv, Rosten Sweeting

Graduate Theses and Dissertations

With the growth in the aerospace industry there has been a trend to optimize the performance of an aircraft by reducing fuel consumption and operational cost. Recent advancements in the field of power electronics have pushed towards the concepts of hybrid electric aircraft also known as more electrical aircrafts. In this work, a custom controller board for an electric aircraft propulsion drive was designed to drive a permanent magnet synchronous motor. Design of the controller board required knowledge of the topology selection and power module selections. Simulations of the system were performed using MATLAB/Simulink to analyze the overall performance ...


Aerodynamics And Vibrations Of A Helicopter Rotor Blade, Mohammad Khairul Habib Pulok 2022 University of New Orleans

Aerodynamics And Vibrations Of A Helicopter Rotor Blade, Mohammad Khairul Habib Pulok

University of New Orleans Theses and Dissertations

The nature of the aerodynamic environment surrounding a helicopter causes a significant amount of vibration to its whole body. Among different sources of vibrations, the aerodynamic loading on the main rotor blade is the major contributor. Therefore, analyzing a rotor blade's vibration characteristics and aerodynamic behavior becomes essential. The vortex characteristics and the wake surrounding a helicopter rotor blade play an important role because they affect the aerodynamic behavior of the rotor blade. An advanced mathematical and computational model of rotor wake and blade vortex gives a better understanding of the helicopter rotor dynamics. This study develops computational models ...


Foundations For Finite-State Modelling Of A Two-Dimensional Airfoil That Reverses Direction, Jake Michael Oscar Welsh 2022 Washington University in St. Louis

Foundations For Finite-State Modelling Of A Two-Dimensional Airfoil That Reverses Direction, Jake Michael Oscar Welsh

McKelvey School of Engineering Theses & Dissertations

Current 3-D finite-state wake models are incapable of simulating a maneuver in which the sign of the free-stream velocity changes direction and the rotor enters its own wake -- as might occur in the case of a helicopter which ascends and then descends. It is the purpose of this work to create a 2-D finite-state wake model which is capable of handling changes in free-stream direction as a precursor to development of a 3-D model that can do the same.

The 2-D finite-state model used for reentry modifications is an existing model created by Peters, Johnson, and Karunamoorthy. By the addition ...


Analysis Of Turbulent Flow Behavior In Helicopter Rotor Hub Wakes, Forrest Mobley 2022 University of Tennessee, Knoxville

Analysis Of Turbulent Flow Behavior In Helicopter Rotor Hub Wakes, Forrest Mobley

Masters Theses

The rotor hub is one of the most important features of all helicopters, as it provides the pilot a means for controlling the vehicle by changing the characteristics of the main and tail rotors. The hub also provides a structural foundation for the rotors and allows for the rotor blades to respond to aerodynamic forces while maintaining controllability and stability. Due to the inherent geometry and high rate of rotation, the rotor hub in its current form acts a large bluff body and is the primary source of parasite drag on the helicopter, despite its relatively small size. The rotor ...


Upscaling And Development Of Linear Array Focused Laser Differential Interferometry For Simultaneous 1d Velocimetry And Spectral Profiling In High-Speed Flows, Kirk Davenport 2022 University of Tennessee, Knoxville

Upscaling And Development Of Linear Array Focused Laser Differential Interferometry For Simultaneous 1d Velocimetry And Spectral Profiling In High-Speed Flows, Kirk Davenport

Masters Theses

In this research a new configuration of linear array-focused laser differential interferometry (LA-FLDI) is described. This measurement expands on previous implementations of LA-FLDI through the use of an additional Wollaston prism. This additional prism expands the typical single LA-FLDI column into two columns of FLDI point pairs. The additional column of probed locations allows for increased spatial sampling of frequency spectra as well as the addition of simultaneous wall normal velocimetry measurements. The new configuration is used to measure the velocity profile and frequency content across a Mach 2 turbulent boundary layer at six wall normal locations simultaneously. Features of ...


Exploring Passive Flow Control Techniques Applied To A Supersonic Multistream Rectangular Nozzle, Emma Dawn Gist 2022 Syracuse University

Exploring Passive Flow Control Techniques Applied To A Supersonic Multistream Rectangular Nozzle, Emma Dawn Gist

Dissertations - ALL

Passive control techniques are applied experimentally to examine different aspects of a supersonic multistream rectangular nozzle representing a modern airframe-integrated variable cycle engine. The flow is comprised of a core stream (M = 1.6) and bypass (M = 1.0) that merge behind a splitter plate and exit through a Single Expansion Ramp Nozzle (SERN) onto an aft-deck. Previous efforts for the nominal nozzle configuration have shown that an instability initiated at the splitter plate trailing edge (SPTE) influences the effectiveness of the third stream as a barrier for the aft-deck and persists through the entire do- main due to its ...


Experimental Characterization Of Additively Manufactured Multi-Feather Wingtip Devices, Patricio Garzon 2022 Embry-Riddle Aeronautical University

Experimental Characterization Of Additively Manufactured Multi-Feather Wingtip Devices, Patricio Garzon

Doctoral Dissertations and Master's Theses

Soaring birds have evolved to fly for long periods of time without flapping their wings. Inspired by the flight of these birds, the proposed thesis presents an experimental investigation focused on wingtip devices designed based on biomimicry. The overarching engineering objective was to reduce the induced drag as a means to improve the fuel efficiency via these experimental wingtips. An associated secondary objective was to establish a method for manufacturing complex structures suitable for wing tunnel testing. A manufacturing technique that involved using composite weaves to reinforce additively manufactured structures was developed. This technique has the potential to reduce manufacturing ...


Sources Of Resonant Vortices In Aero-Acoustics Resonance From Tandem Flat Plates, Atef El Khatib, Ahmad Al Miaari, Ali Hammoud 2022 Engineer, Faculty of Engineering, Beirut Arab University

Sources Of Resonant Vortices In Aero-Acoustics Resonance From Tandem Flat Plates, Atef El Khatib, Ahmad Al Miaari, Ali Hammoud

BAU Journal - Science and Technology

Aero-acoustic resonance in flows around flat plates is a major design concern in various practical applications, especially turbomachinery and heat exchangers, due to its significant effects on fatigue rates and radiated noises intensity. Although research has been intensive on the topic, there is still a lot to be understood for effective resonance prediction and control. Resonance in tandem plate systems is characterized by a double response. This study, investigates for the first time, the flow mechanisms responsible for the generation of low-velocity and high-velocity resonances of the double resonance response. Experimental testing and numerical simulation showed that low-velocity resonance vortices ...


Structural Dynamics Of Awt-27 Wind Turbine Blade, Amr Ismaiel 2022 Future University in Egypt (FUE)

Structural Dynamics Of Awt-27 Wind Turbine Blade, Amr Ismaiel

Future Engineering Journal

Wind energy is one of the world’s current leading renewable energy resources. One of the major aspects of studying wind turbines is the structural dynamics for the turbine structure including blades and support structure. In the current work, the blades of the Advanced Wind Turbine (AWT-27) are investigated in a dynamic approach. Different wind fields have been generated for the study to provide different Design Load Conditions (DLCs). Three laminar wind velocities of 5 m/s, 12 m/s, and 17 m/s were simulated. Turbulent wind flow fields have also been generated at the three standard classes A ...


Experimental And Computational Investigation Of Divergent Thrust Losses In Rocket Nozzles, Vaibhav Arya Graduate Engineer, Anushka Sunil Kapse Post Graduate Student 2022 Sandip University, MH, INDIA

Experimental And Computational Investigation Of Divergent Thrust Losses In Rocket Nozzles, Vaibhav Arya Graduate Engineer, Anushka Sunil Kapse Post Graduate Student

Graduate Research in Engineering and Technology (GRET)

The nozzle is a critical component of any rocket engine because it transforms high pressure and high temperature (with sluggish net velocity) within the combustion chamber into high velocity but low pressure. Individually, the molecules in the mixed propellants have rapid velocity in the combustion chamber, but directions are randomly pointing in all directions. A convergent-divergent nozzle, also known as a CD nozzle, is fashioned like a tube with two bulging ends and a thin part in the center. This structure/design provides the nozzle with a balanced shape. By turning the flow's heat energy into kinetic energy, the ...


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