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Computational Investigation Of Perforated Plate Film Cooling Utilizing Conjugate Heat Transfer, Jonathan Sippel 2021 Embry-Riddle Aeronautical University

Computational Investigation Of Perforated Plate Film Cooling Utilizing Conjugate Heat Transfer, Jonathan Sippel

PhD Dissertations and Master's Theses

The accuracy of modern state-of-practice computational fluid dynamics approaches in predicting the cooling effectiveness of a perforated plate film-cooling arrangement is evaluated in ANSYS Fluent. A numerical investigation is performed using the Reynolds Averaged Navier Stokes equations and compared to NASA Glenn’s available Turbulent Heat Flux 4 experimental measurements collected as a part of the Transformational Tools and Technologies Project. A multiphysics approach to model heat conduction through the solid geometry is shown to offer significant improvements in wall temperature and film effectiveness prediction accuracy over the standard adiabatic wall approach. Additionally, localized gradient-based grid adaption is analyzed using ...


Analysis Of Ship Airwakes Using Modal Decomposition, Nicholas Zhu 2021 Embry-Riddle Aeronautical University

Analysis Of Ship Airwakes Using Modal Decomposition, Nicholas Zhu

PhD Dissertations and Master's Theses

The three-dimensional, unsteady, and turbulent airwake produced by a scaled model of a generic Navy ship (Simple Frigate Shape No. 2) was investigated in a low-speed wind tunnel. Stereoscopic, time-resolved particle image velocimetry (TR-PIV) measurements were made at six different crosswise planes over the flight deck region of the ship model, with and without the effect of a simulated atmospheric boundary layer (ABL).

Spatiotemporal analyses of the TR-PIV measurements were performed using modal decomposition, and the modes were decomposed further based on the frequency contents of their time dynamics. This approach allowed an inspection of the individual scales of the ...


Design, Construction, And Flight Of A Remote-Controlled Aircraft For The 2020-21 Aiaa Dbf Competition, Jonathan A. Dixon, Caleb Weatherly, Satyam Mistry, Killian Samuels, Ethan Cerrito, Caleb Morgan, Sanghyeok Park, Sam Pankratz, Jamison Murphree 2021 University of Tennessee, Knoxville

Design, Construction, And Flight Of A Remote-Controlled Aircraft For The 2020-21 Aiaa Dbf Competition, Jonathan A. Dixon, Caleb Weatherly, Satyam Mistry, Killian Samuels, Ethan Cerrito, Caleb Morgan, Sanghyeok Park, Sam Pankratz, Jamison Murphree

Chancellor’s Honors Program Projects

No abstract provided.


Sensitivity And Estimation Of Aerodynamic, Propulsion, And Inertial Parameters For Rudderless Aircraft Using Simulation, Jaden Thurgood 2021 Utah State University

Sensitivity And Estimation Of Aerodynamic, Propulsion, And Inertial Parameters For Rudderless Aircraft Using Simulation, Jaden Thurgood

All Graduate Theses and Dissertations

A technique known as system identification is often used in aircraft design and testing to understand and validate the mathematical parameters that describe the aircrafts stability and handling characteristics. System identification can be thought of as the inverse of simulation. In the world of system identification, we have a physical system that we seek to understand in more detail by monitoring the system with an array of sensors. In short, we conduct tests of an aircraft while recording the inputs and response outputs. Then we take the input and output data and run it through an algorithm that seeks to ...


Analysis On Fuel Options For Scramjet Engines With The Study To Lower The Starting Mach Number, Sumantra Luitel, Gagan Dangi 2021 University of Mississippi

Analysis On Fuel Options For Scramjet Engines With The Study To Lower The Starting Mach Number, Sumantra Luitel, Gagan Dangi

Honors Theses

The main objectives of this report were to perform analysis of an ideal scramjet engine, to assess the influence of fuel on endurance factor, and the possibility of lowering the starting Mach Number of the scramjet. In the first part, an ideal cycle parametric analysis was conducted on three different fuels i.e. Liquid Hydrogen (LH2), Jet Propellant 7 (JP-7), and Rocket Propellant (RP-1), taking into account their availability, physical properties, current uses, and potential uses. The detailed analysis is done largely relying on a 9 step Parametric Cycle Analysis technique to study how fuel properties influence the variation of ...


Airplane Pitch Response To Rapid Configuration Change: Flight Test And Safety Assessment, Ralph Kimberlin, Markus Wilde, Brian Kish, Isaac Silver 2021 Florida Institute of Technology

Airplane Pitch Response To Rapid Configuration Change: Flight Test And Safety Assessment, Ralph Kimberlin, Markus Wilde, Brian Kish, Isaac Silver

Journal of Aviation Technology and Engineering

This paper examines airplane response to rapid flap extension on seven general aviation airplanes. The scenario involves a pilot flying in the traffic pattern becoming distracted, abruptly extending flaps while looking outside the airplane, and failing to notice airspeed and pitch-attitude changes. The airplanes tested reached pitch forces of up to 36 lbf, meeting FAA requirements but exceeding the capability of 55% of the population. Flight data showed a pitch-up to more than 30˚ in 5 s after flap extension, causing airspeed to drop below stall speed for four of the airplanes. At traffic pattern altitudes, stalling an airplane can ...


Hayabusa2'S Superior Solar Conjunction Mission Operations: Planning And Post-Operation Results, Stefania Soldini, Hiroshi Takeuchi, Sho Taniguchi, Shota Kikuchi, Yuto Takei, Go Ono, Masaya Nakano, Takafumi Ohnishi, Takanao Saiki, Yuichi Tsuda, Fuyuto Terui, Naoko Ogawa, Yuya Mimasu, Tadateru Takahashi, Atsushi Fujii, Satoru Nakazawa, Kent Yoshikawa, Yusuke Oki, Chikako Hirose, Hirotaka Sawada, Tomohiro Yamaguchi, Makoto Yoshikawa 2021 Department of Mechanical, Materials and Aerospace Engineering, University of Liverpool, Liverpool L69 3BX, UK;Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara 252-5210, Japan

Hayabusa2'S Superior Solar Conjunction Mission Operations: Planning And Post-Operation Results, Stefania Soldini, Hiroshi Takeuchi, Sho Taniguchi, Shota Kikuchi, Yuto Takei, Go Ono, Masaya Nakano, Takafumi Ohnishi, Takanao Saiki, Yuichi Tsuda, Fuyuto Terui, Naoko Ogawa, Yuya Mimasu, Tadateru Takahashi, Atsushi Fujii, Satoru Nakazawa, Kent Yoshikawa, Yusuke Oki, Chikako Hirose, Hirotaka Sawada, Tomohiro Yamaguchi, Makoto Yoshikawa

Astrodynamics

In late 2018, the asteroid Ryugu was in the Sun’s shadow during the superior solar conjunction phase. As the Sun-Earth-Ryugu angle decreased to below 3∘, the Hayabusa2 spacecraft experienced 21 days of planned blackout in the Earth-probe communication link. This was the first time a spacecraft had experienced solar conjunction while hovering around a minor body. For the safety of the spacecraft, a low energy transfer trajectory named Ayu was designed in the Hill reference frame to increase its altitude from 20 to 110 km. The trajectory was planned with the newly developed optNEAR tool and validated with real ...


Development Of A Hybrid Particle Continuum Solver, Anthony J. Gay 2021 California Polytechnic State University, San Luis Obispo

Development Of A Hybrid Particle Continuum Solver, Anthony J. Gay

Master's Theses

When simulating complex flows, there are some physical situations that exhibit large fluctuations in particle density such as: planetary reentry, ablation due to arcing, rocket exhaust plumes, etc. When simulating these events, a high level of physical accuracy can be achieved with kinetic methods otherwise known as particle methods. However, this high level of physical accuracy requires large amounts of computation time. If the simulated flow is in collisional equilibrium, then less computationally intensive continuum methods, otherwise known as fluid methods, can be utilized. Hybrid Particle-Continuum (HPC) codes attempt to blend particle and fluid solutions in order to reduce computation ...


Ram Air-Turbine Of Minimum Drag, Raymond Akagi 2021 California Polytechnic State University, San Luis Obispo

Ram Air-Turbine Of Minimum Drag, Raymond Akagi

Master's Theses

The primary motivation for this work was to predict the conditions that would yield minimum drag for a small Ram-Air Turbine used to provide a specified power requirement for a small flight test instrument called the Boundary Layer Data System. Actuator Disk Theory was used to provide an analytical model for this work.

Classic Actuator Disk Theory (CADT) or Froude’s Momentum Theory was initially established for quasi-one-dimensional flows and inviscid fluids to predict the power output, drag, and efficiency of energy-extracting devices as a function of wake and freestream velocities using the laws of Conservations of Mass, Momentum, and ...


Data-Driven Tools Guided By First-Principles For Scale Modeling, Sadegh Poozesh 2021 Tuskegee university

Data-Driven Tools Guided By First-Principles For Scale Modeling, Sadegh Poozesh

Progress in Scale Modeling, an International Journal

For decades, traditional scale-modeling techniques have been relying on first-principles models (FPMs). FPMs have been used to find non-dimensional numbers (PIs) and identify normalized underlying forces and energies behind the phenomenon in focus. The two main challenges with FPM-based PIs extraction are finding the relevant PIs and proper correlations between PIs. The emergence and surge of data-driven modeling (DDM) provide a new opportunity to leverage experimental data in model development across scales/plants. In this paper, first, the two mentioned issues in PIs development will be elaborated to reveal the gap, and second, a new insight into scale modeling and ...


Measurements Of Wind Turbine Wake Evolution And Trajectory During Morning Boundary Layer Transition And Under Wake Steering Conditions Via Unmanned Aerial Vehicles, Stewart Nelson 2021 University of Kentucky

Measurements Of Wind Turbine Wake Evolution And Trajectory During Morning Boundary Layer Transition And Under Wake Steering Conditions Via Unmanned Aerial Vehicles, Stewart Nelson

Theses and Dissertations--Mechanical Engineering

In July of 2019, a flight campaign was conducted using semi-autonomous Unmanned Aerial Vehicles (UAVs) at the Port Alma Kruger Energy wind farm in Ontario, Canada, to study various aspects of wind turbine wake evolution. Horizontal transects across the wakes were measured using modified fixed-wing aircraft fitted with a five-hole probe to measure the wind velocity vector. Reference boundary layer conditions were measured by an octocopter with an assortment of mounted sensors flying vertical profiles upstream of the turbines. Three experiments were conducted during the campaign, which consisted of a study on wake behavior during the morning boundary layer transition ...


Non-Equilibrium Behavior Of Large-Scale Axial Vortex Cores, Robert L. Ash, Irfan R. Zardadkhan 2021 Old Dominion University

Non-Equilibrium Behavior Of Large-Scale Axial Vortex Cores, Robert L. Ash, Irfan R. Zardadkhan

Mechanical & Aerospace Engineering Faculty Publications

A logical basis for incorporating pressure non-equilibrium and turbulent eddy viscosity in an incompressible vortex model is presented. The infrasonic acoustic source implied in our earlier work has been examined. Finally, this non-equilibrium turbulent vortex core is shown to dissipate mechanical energy more slowly than a Burgers vortex, helping us to explain the persistence of axial vortices in nature. Recent molecular dynamics simulations replicate aspects of this non-equilibrium pressure behavior.


Numerical Investigations Of Transient Wind Shear From Passing Vehicles Near A Road Structure (Part I: Unsteady Reynolds-Averaged Navier-Stokes Simulations), Hamid Rahai, Assma Begum 2021 California State University, Long Beach

Numerical Investigations Of Transient Wind Shear From Passing Vehicles Near A Road Structure (Part I: Unsteady Reynolds-Averaged Navier-Stokes Simulations), Hamid Rahai, Assma Begum

Mineta Transportation Institute Publications

In this research, the authors performed unsteady numerical simulations of a moving Ahmed body under a freeway overpass at different distances from the bridge columns in order to evaluate transient wind shear and the wind load on these columns. Results have shown that when the vehicle is at 0.75W distance from the bridge columns, an unsteady wind speed of up to 24 m/s is observed at the columns with a pressure coefficient difference of 0.9. Here W is the width of the vehicle. These results indicate with an appropriate system for harnessing these wind energy potentials, significant ...


Wind Tunnel Data Acquisition System Development Using Labview, Riley Bishop 2021 Western Kentucky University

Wind Tunnel Data Acquisition System Development Using Labview, Riley Bishop

Mahurin Honors College Capstone Experience/Thesis Projects

Utilizing an educational-purpose wind tunnel, a data acquisition system through LabVIEW was created to experimentally analyze the aerodynamic forces experienced by objects in uniform external flow by automatically performing trials and interpreting electrical measurement signals. To verify experimental results from pressure distribution data around an object, a force balance was designed to mount objects stationarily in the wind tunnel test section while directly measuring the total lift and drag forces, calculating the pitching moment (for airfoils), and monitoring the angle of attack. The force balance design includes three load cells, one for measuring drag force and two for measuring total ...


Design And Testing Of A Feed-Forward Control System For Deployable Vortex Generators Dependent On Angle Of Attack, Solomon B. Whitmire, Christopher J. Chapanar, Kirklin M. Anderson, Nickalus R. Amon, Daniel W. Chech 2021 The University of Akron

Design And Testing Of A Feed-Forward Control System For Deployable Vortex Generators Dependent On Angle Of Attack, Solomon B. Whitmire, Christopher J. Chapanar, Kirklin M. Anderson, Nickalus R. Amon, Daniel W. Chech

Williams Honors College, Honors Research Projects

A vortex generator (VG hereafter) is a common feature of an aircraft wing that disturbs the flow on the leading edge of the wing, thus energizing the boundary layer and reducing flow separation. For an aircraft experiencing flow separation, VGs can increase the lift-to-drag ratio of the wing and prevent stall; however, if flow separation isn’t an issue, the unnecessary frontal area of the VGs has the potential to produce parasitic drag. This study seeks to determine whether the use of a deployment system can improve the performance of VG’s by raising or lowering them depending on the ...


A Model For Inhalation Of Infectious Aerosol Contaminants In An Aircraft Passenger Cabin, Bert A. Silich 2021 Vector Vantage LLC

A Model For Inhalation Of Infectious Aerosol Contaminants In An Aircraft Passenger Cabin, Bert A. Silich

International Journal of Aviation, Aeronautics, and Aerospace

Aerosol contamination of an aircraft cabin by infectious passengers is a concern of passengers, aircrew and the aviation industry. This may be especially important during a pandemic, such as COVID-19, where the full extent of aerosol transmission is not well understood. A statistical method to determine the number of infectious passengers on board along with a mathematical model estimating the contaminant concentration of aerosols in the cabin and the number of inhaled infectious particles by passengers is presented. An example is used to demonstrated how the results can be estimated during normal operations and emergency conditions with malfunctions of the ...


Comparative Study On The Prediction Of Aerodynamic Characteristics Of Mini - Unmanned Aerial Vehicle With Turbulence Models, Somashekar V, Immanuel Selwyn Raj A 2021 Vellore Institute of Technology, Vellore

Comparative Study On The Prediction Of Aerodynamic Characteristics Of Mini - Unmanned Aerial Vehicle With Turbulence Models, Somashekar V, Immanuel Selwyn Raj A

International Journal of Aviation, Aeronautics, and Aerospace

When dealing with CFD simulations the turbulent nature is seen on most of the engineering flows and these flows need to be solved. Reliable and applicable CFD outputs can be obtained from the accurate modelling of the turbulence as it is one of the most vital elements of CFD modelling. The RANS equations are extensively employed to analyse the complex flows over aircraft and for this purpose, a turbulence model is needed for turbulent flow analyses. Compatible turbulence must be chosen for the exact predictions of aircraft aerodynamic characteristics. In this report, numerical analyses of Mini-UAV are done to compare ...


Aerodynamic Performance Analysis Of Co-Flow Jet Airfoil, C M Vigneswaran, Vishnu Kumar G C 2021 Research Scholar, School of Aeronautical Science, Hindustan Institute of Technology and Sciences (HITS), Chennai

Aerodynamic Performance Analysis Of Co-Flow Jet Airfoil, C M Vigneswaran, Vishnu Kumar G C

International Journal of Aviation, Aeronautics, and Aerospace

The work in this paper aims to increase the maximum lift coefficient of the airfoil by implementing the co-flow jet concept on NACA 0018 airfoil and also to investigate the performance of co-flow jet (CFJ) airfoil. To conduct numerical solution, RANS equations have been solved for 2D incompressible and unsteady flow using the Spalart-Allmaras turbulence model. The suction surface of the airfoil is modified by placing the injection slot near the leading edge and the suction slot near the trailing edge. A small mass of air is withdrawn into the airfoil suction slot, pressurized by a pumping system located inside ...


Identification Of Wind-Induced Hazard Zones Impacting Uas Bridge Inspection, Jack J. Green, John Mott 2021 Purdue University

Identification Of Wind-Induced Hazard Zones Impacting Uas Bridge Inspection, Jack J. Green, John Mott

International Journal of Aviation, Aeronautics, and Aerospace

Unmanned Aerial Systems (UAS) continue to grow in both popularity and utility within the national airspace system. The use of commercial UAS for civil inspection, specifically that of bridge structures, is becoming commonplace among practitioners and academics alike. The development of an integrated bridge-inspection hazard model provides a way for UAS operators to prepare for and respond to changing environmental conditions that could otherwise prevent a successful UAS flight. The interaction of wind-induced airflow with bridge surfaces creates an aerodynamic wake that can result in hazardous conditions for a UAS platform operating in close proximity. An analysis of this airflow ...


Aerodynamic Characterization Of Bio-Mimicked Pleated Dragonfly Aerofoil, Md Akhtar Khan, Chinmaya Padhy 2021 GITAM University

Aerodynamic Characterization Of Bio-Mimicked Pleated Dragonfly Aerofoil, Md Akhtar Khan, Chinmaya Padhy

International Journal of Aviation, Aeronautics, and Aerospace

The work inspired by the dragonfly wing corrugation positioned at the front wing's radius section lying at 40% of the total wingspan of forewing from the root section. During gliding flight, dragonfly wings presumed to be an ultra-light aerofoil due to its well-defined cross-sectional corrugation. The aerodynamic simulation carried out to understand the aerodynamic performance of a bio-mimetic dragonfly corrugated airfoil at low Reynolds number range of 75000-150000 to explore the potential advantages of pleated airfoils at a varying angle of attack from 0° to 12°. CFD analysis accomplished by using ANSYS Fluent to understand the aerodynamic performance of ...


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