Aerodynamics and Fluid Mechanics Commons^™

Steady And Transient Study Of Conjugate Heat Transfer In Regenerative Cooled Nozzle, Khaled Bensayah, Khadidja Kamri

Emirates Journal for Engineering Research

The Heat transfer is one of the most serious challenges that exist in a supersonic nozzle flow. The combustion chamber wall and the nozzle are exposed to high-temperature gases during combustion and gas expansion, which can eventually lead to structural failure. This paper reports a computational study of steady and transient conjugate heat transfer in regenerative water cooled nozzle. Numerical computation solved Reynolds-averaged equations based on RSM-Omega turbulence model coupling with solid-phase heat conduction equation and with coolant-phase. The effect of four inlet cooled approach length 0 inch, 6 inch, 12 inch and 18 inch are studied and validated against …

Studies Of Flowfields And Dynamic Stability Characteristics Of A Quadrotor, Engin Baris

Mechanical & Aerospace Engineering Theses & Dissertations

Electric multirotor air vehicles have become a pervasive technology and research topic in industry, academia, and daily life, and small quadrotors are one of the most preferred designs in the multirotor marketplace. However, the configuration of the quadrotors makes aerodynamic interaction effects one of the key factors of the vehicle performance in both hover and non-axial forward flight conditions.

In the present work, aerodynamic characteristics of the cross-configured small quadrotor in hover, edgewise, and maneuvering flight modes were investigated in detail by performing static and dynamic wind tunnel tests at various RPM levels, wind speeds, pitch and yaw angles, and …

Superfly Amphibian, Devonte Andrews, Ahmed Hamza, Kwesi Onumah, Eva Sanchez

Senior Design Project For Engineers

Following a Short Takeoff and Landing (STOL) mission profile, this seaplane is designed to carry 19 passengers and 1 flight crew with a range of 200 nautical miles. The seaplane is equipped with two turbo-prop engines and is economically comparable to current seaplanes in terms of servicing and operating expenses. The aircraft is capable of operating in remote locations with limited infrastructure due to its STOL abilities, allowing for increased access to difficult-to-reach areas. The seaplane's design incorporates modern materials and technologies to enhance efficiency, safety, and comfort for passengers and crew. The aircraft's versatility and cost-effectiveness make it an …

A Simulation Of The Impacts Of Climate Change On Civil Aircraft Takeoff Performance, Thomas D. Pellegrin

Doctoral Dissertations and Master's Theses

Climate change affects the near-surface environmental conditions that prevail at airports worldwide. Among these, air density and headwind speed are major determinants of takeoff performance, and their sensitivity to global warming carries potential operational and economic implications for the commercial air transport industry. Previous archival and prospective research observed a weakening in headwind strength and predicted an increase in near-surface temperatures, respectively, resulting in an increase in takeoff distances and weight restrictions. The main purpose of the present study was to update and generalize the extant prospective research using a more representative sample of worldwide airports, a wider range of …

Design Of An Internal Osculating Waverider Intake, Mark E. Noftz, Andrew J. Shuck, Joseph S. Jewell, Jonathan Poggie, Andrew N. Bustard, Thomas J. Juliano, Nicholas J. Bisek

Publications

The design of an inward-turning, high-speed, three-dimensional streamline traced intake is presented from osculating axisymmetric theory. To satisfy the osculating intake design criteria, a stitched Busemann diffuser and Internal Conical Flow-A solution is used as the basic isentropic compressive streamline. This new contour provides efficient compression, high flow uniformity, and straight leading edge shocks of equal strength. Additionally, a novel method for constructing the inlet cowl is presented. The combined process leads to a new method of high-speed intake design. A generic shape-transitioned intake is constructed and named the Indiana Inlet for the Indiana universities that contributed to the project. …

Understanding Unsteady Corner Separation Within Wing-Body Junction Flows, Paul G. Winner

Doctoral Dissertations and Master's Theses

Wing-body junction flows, formed at the interface between a wing and fuselage surface, are a complex, coupled, three-dimensional, turbulent flow field. This thesis focused on the unsteady corner separation that develops at the trailing edge of this wing-body junction under certain conditions. A NACA 0015 wing mounted on a flat plate at an angle of attack of 13°was used as the model junction flow field. The wing had an aspect ratio of 8 with a linear washout twist of 15°. The Reynolds number based on the wing chord was Re_c = 4.5 × 10⁵. Time-dependent stereoscopic particle …

Effect Of Spray Rails On Takeoff Performance Of Amphibian Aircraft, Soham Bahulekar

Doctoral Dissertations and Master's Theses

Amphibian aircraft have seen a rise in popularity in the recreational and utility sectors due to their ability to take off and land on both land and water, thus serving a myriad of purposes such as aerobatics, surveillance, and firefighting. The design of such seaplanes requires to be both aerodynamically and hydrodynamically efficient, especially during the takeoff phase. In the past, naval architects have implemented ways to make boats, yachts, and large ships more efficient; one of them being the addition of chine strips and spray rails on the hull. This thesis study explores the possibility of implementing spray rails …

Structural Loads And Preliminary Structural Design For A World Speed Record-Breaking Turbo-Prop Racing Airplane, Matthew G. Slymen

Master's Theses

The Cal Poly SLO Turbo-Prop Racer project aims to design a world speed record-breaking aircraft, capable of flying more than 550 miles per hour on a 3-kilometer closed course. To further this endeavor, this thesis presents the calculations of load distributions across the aircraft’s wing and tail and preliminary structural estimates of primary structural components for verification of the loads calculations and for use in a future finite element model. The aircraft’s fundamental design characteristics effect on the structure of the aircraft, namely the unique Y-tail design, are first examined. Then, loads are calculated in accordance with the regulation dictated …

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 …

A Decoupled Engineering Methodology For Accurate Prediction Of Ablative Surface Boundary Conditions In Thermal Protection Systems, Justin Cooper

Theses and Dissertations--Mechanical and Aerospace Engineering

The main objective of the present work is to demonstrate a method for prediction of aerothermal environments in the engineering design of hypersonic vehicles as an alternative to the current heritage method. Flat plate and stagnation point boundary layer theory require multiple assumptions to establish the current engineering paradigm. Chief among these assumptions is the similarity between mass and heat transfer. Origins of these assumptions are demonstrated and their relationship to conservative engineering design is analyzed, as well as conditions where they possibly break down. An alternative approach for assessing aerothermal environments from the fluid domain is presented, which permits …

Aerodynamic Analysis Of Damage State Missiles Using Overset Meshing Techniques For Application To Computational Fluid Dynamics Simulation, Jonathan A. D'Alessio

Graduate Theses, Dissertations, and Problem Reports (ETD)

Significant research over the years has aimed to redefine the flight capabilities of aircraft after sustaining structural damage to critical components. Flight survivability and controllability are key areas of concern when designing fault-tolerant flight control systems to handle a wide range of potential scenarios. However, there is a lack of research on the impact of physically damaged missile systems. Missile counter-defense and intercept capabilities have become more advanced as the United States has focused heavily on these areas over the years. Damaged missiles due to a kinetic intercept capability present an opportunity for analysis of the post-damage implications on flight …

Analyzing The Effect Of Delta Airlines' Fleet Upgrade On Operations At Atlanta-Hartsfield Jackson International Airport, Carlos Alberto Castro, Shlok Misra

Publications

Commercial aviation has seen a growth in terms of passengers traveled and flights operated in the past decade (BTS, 2020). To cope up with this growth, airlines adopt various strategies such as network expansion and fleet upgrades. Airlines adopt fleet upgrade strategies to modernize their fleet, reduce costs, expand network coverage, and improve customer loyalty and experience. Research suggests that change in wake turbulence categorization and aircraft performance can directly impact the movements and delays at an airport. For this study, Delta Airline's fleet upgrade program and its effect on operating parameters at Atlanta-Hartsfield Jackson International Airport were analyzed. The …

Active Control Of Coherent Structures In An Axisymmetric Jet, Michael Marques Goncalves

Doctoral Dissertations and Master's Theses

The primary objective of this work is to develop high-fidelity simulation model for jet noise control predictions and quantify the sound reduction when an external source frequency mode excitation is imposed on the jet flow. Whereas passive approaches using mixing devices, such as chevrons, have been shown to reduce low-frequency noise in jet engines, such approaches incur a performance penalty since they result in a reduced thrust. To avoid a performance penalty in reducing jet noise, the current work investigates a open-loop active noise control (ANC) system that utilizes a unsteady microjet actuator on the nozzle lip in the downstream …

Design And Flight-Path Simulation Of A Dynamic-Soaring Uav, Gladston Joseph

Doctoral Dissertations and Master's Theses

We address the development of a dynamic-soaring capable unmanned aerial vehicle (UAV) optimized for long-duration flight with no on-board power consumption. The UAV’s aerodynamic properties are captured with the integration of variable fidelity aerodynamic analyses. In addition to this, a 6 degree-of-freedom flight simulation environment is designed to include the effects of atmospheric wind conditions. A simple flight control system aids in the development of the dynamic soaring maneuver. A modular design paradigm is adopted for the aircraft dynamics model, which makes it conducive to use the same environment to simulate other aircraft models. Multiple wind-shear models are synthesized to …

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

Doctoral 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 the …

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 …

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 Energy. …

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 and Aerospace 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, …

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 …

Time Domain Boundary Element Method Prediction Of Noise Shielding By A Naca 0012 Airfoil, Douglas M. Nark, Fang Q. Hu

Mathematics & Statistics Faculty Publications

As aircraft noise constraints become more stringent and the number/mixture of aircraft configurations grows, it becomes more important to understand the interaction of individual aircraft noise sources with nearby aircraft structures. Understanding these interactions and exploring possible approaches to mitigate or exploit their acoustic impact is essential for overcoming key noise barriers. This paper describes the further validation of a time domain boundary element approach for the prediction of the interactions between incident noise sources and nearby aircraft structures. Predictions were completed for multiple source locations and comparisons of these results with measured data are presented. Overall, very good agreement …

Albatross And Falcon Inspired Bionic Uav: An Aerodynamic Analysis, Bilji C. Mathew, Sagar K. Sahu, Prantik Dutta, Rushi Savale, Muruga Lal Jeyan Jv Dr.

International Journal of Aviation, Aeronautics, and Aerospace

The drone industry yearns for enhanced aerodynamic performance. In order to achieve this feat, researchers and engineers are trying to mimic the natural flyers due to their aerodynamic optimality. One such flyer, the Albatross is an inspiration for many marine drones due to its planform and aerodynamic efficiency. The wing of the plan form is designed and simulated to study its properties. The Bell-Shaped Lift Distribution is incorporated for higher efficiency and elimination of the total downwash produced in case of an Elliptical Lift Distribution. A blended wing body inspired by the Falcon is used for smoother airflow interactions. Furthermore, …

Celebrating 90-Orbits Around The Sun, Stafford Air & Space Museum

Programs

In celebration of the 90th birthday of Oklahoma astronaut and aerospace legend, Gen. Thomas P. Stafford, the Stafford Air & Space Museum in Weatherford, Oklahoma is offering free admission on September 17th, 2020.

Unless stated otherwise within this repository collection, all materials are shared under the following Creative Commons license: [Creative Commons Attribution-NonCommercial 4.0 International License].

A Study Of The Design Of Adaptive Camber Winglets, Justin J. Rosescu

Master's Theses

A numerical study was conducted to determine the effect of changing the camber of a winglet on the efficiency of a wing in two distinct flight conditions. Camber was altered via a simple plain flap deflection in the winglet, which produced a constant camber change over the winglet span. Hinge points were located at 20%, 50% and 80% of the chord and the trailing edge was deflected between -5° and +5°. Analysis was performed using a combination of three-dimensional vortex lattice method and two-dimensional panel method to obtain aerodynamic forces for the entire wing, based on different winglet camber configurations. …

A Study Of The Utilization Of Panel Method For Low Aspect Ratio Wing Analysis, William Barton D. Newey

Master's Theses

This study demonstrates the applicability of using a modified application strategy of panel method to analyze low aspect ratio wings at preliminary design phases. Conventional panel methods fail to capture the leading edge vortex (LEV) that is shed by wings with low aspect ratios, typically below 2 depending on planform. This aerodynamic phenomenon contributes to a significant amount of the lift of these wings and the result is a drastic underestimation of the lift characteristics when analyzed by conventional panel method. To capture the effect of the leading edge vortex, a panel method code was used with an extended definition …

Conceptual Design Of A South Pole Carrier Pigeon Uav, Kendrick M. Dlima

Master's Theses

Currently, the South Pole has a large data problem. It is estimated that 1.2 TB of data is being produced every day, but less than 500 GB of that data is being uploaded via aging satellites to researchers in other parts of the world. This requires those at the South Pole to analyze the data and carefully select the parts to send, possibly missing out on vital scientific information. The South Pole Carrier Pigeon will look to bridge this data gap.

The Carrier Pigeon will be a small unmanned aerial vehicle that will carry a 30 TB solid-state hard drive …

A Study Of The Standard Cirrus Wing Lift Distribution Versus Bell Shaped Lift Distribution, William H. Bergman

Master's Theses

This thesis discusses a comparison of the differences in aerodynamic performance of wings designed with elliptical and bell-shaped lift distributions. The method uses a Standard Cirrus sailplane wing with a lift distribution associated with the induced drag benefits of an elliptical distribution (span efficiency = 0.96) as the basis of comparison. The Standard Cirrus is a standard class sailplane with 15-meter wingspan that was designed by Schempp-Hirth in 1969. This sailplane wing was modeled and analyzed in XFLR5, then validated against existing wind tunnel airfoil data, and Standard Cirrus flight test data. The root bending moment of the baseline wing …

Aircraft Leading Edge Strakes On Conventional Naca Wings, Anthony Pirone

Discovery Day - Prescott

The prevention of stall on aircraft wings has been a great challenge over the history of airplanes. As the aircraft become more and more complex, it becomes harder to fit high lift devices and leading-edge devices onto high camber, supercritical airfoil aircraft wings. In the fighter jet class of aircraft the obstacle of stall is usually delayed by the implementation of leading-edge root extensions or strakes. Strakes create a tip vortice along the sharp leading edge that transitions over the surface of the wing preventing separation on both the upper and lower surface of the wing allowing the fighter jet …

Sae Aero West Heavy Lift Competition Team - Eaglenautics, Anthony Pirone, Evan Stuart, Jessica Millard, Nathaniel Scott

Discovery Day - Prescott

ERAU’s SAE Aero Design West Competition team encourages students of all majors who have an interest in the design of heavy-lift cargo and passenger aircraft to design, build, and fly a large RC aircraft to meet a new set of regulations each competition year. Since the team, Eaglenautics, was founded in 2017 it has successfully been to competition once in April 2019 in California. The team’s aircraft flew 4 out of 5 flight rounds, passed all technical inspections, and is now on display in ERAU’s Aero-Fab in the AXFAB. The 2020 competition requirements are unique in that the cargo’s weight-to-volume …

Design Of Banner Tow Mechanism For Bush Plane, Kyle Ciarrone, Ivan Martin, Rishabh Gadi, Tyler Brandt

Williams Honors College, Honors Research Projects

The 2019-2020 AIAA DBF objective was to design, build, and test a banner-towing bush plane that carries wooden passengers and luggage. Senior members on the team undertook the creation of the banner tow mechanism subsystem as their senior design project on behalf of the design team due to the challenge of its mechanical design and the aerodynamic considerations regarding its placement and enclosure aboard the aircraft. The competition as well as access to campus resources were canceled due to COVID-19, so full testing and integration of the mechanism was not achieved. However, the engineering design process was experienced from the …

Low-Cost Skewed Redundant Imu Configuration For State-Space Recovery In A Saturated Environment, Levi S. Hubbard

Graduate Theses, Dissertations, and Problem Reports (ETD)

Low-cost sensors for state space determination can be used successfully for ground vehicles, robots, unmanned aerial vehicles, and Internet-of-Things applications. When a high fidelity Inertial Measurement Unit (IMU) cannot be obtained for state space determination, low-cost sensors can be used to satisfactory standards, despite their limitations in capabilities, by using various implementation techniques. The research group was experimentally investigating state space information of an unstable flying vehicle for motion simulation validation. The high fidelity motion capture system would intermittently lose track of the flight vehicle which lost critical flight data.

The goal was to determine the potential of low-cost off-the-shelf …