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Aerodynamics and Fluid Mechanics Commons

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All Articles in Aerodynamics and Fluid Mechanics

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Detailed Velocity And Heat Transfer Measurements In An Advanced Gas Turbine Vane Insert Using Magnetic Resonance Velocimetry And Infrared Thermometry, Michael Benson, David Bindon CDT'19, Mattias Cooper CDT'19, F. Todd Davidson, Benjamin Duhaime CDT'19, David Helmer, Robert Woodings CDT'19, Bret P. Van Poppel, Christopher J. Elkins, John P. Clark 2022 United States Military Academy

Detailed Velocity And Heat Transfer Measurements In An Advanced Gas Turbine Vane Insert Using Magnetic Resonance Velocimetry And Infrared Thermometry, Michael Benson, David Bindon Cdt'19, Mattias Cooper Cdt'19, F. Todd Davidson, Benjamin Duhaime Cdt'19, David Helmer, Robert Woodings Cdt'19, Bret P. Van Poppel, Christopher J. Elkins, John P. Clark

West Point Research Papers

This work reports the results of paired experiments for a complex internal cooling flow within a gas turbine vane using magnetic resonance velocimetry (MRV) and steady-state infrared (IR) thermometry. A scaled model of the leading edge insert for a gas turbine vane with multi-pass impingement was designed, built using stereolithography fabrication methods, and tested using MRV techniques to collect a three-dimensional, three-component velocity field data set for a fully turbulent test case. Stagnation and recirculation zones were identified and assessed in terms of impact on potential cooling performance. A paired experiment employed an IR camera to measure the temperature profile ...


Simulating The Effects Of Floating Platforms, Tilted Rotors, And Breaking Waves For Offshore Wind Turbines, Hannah Johlas 2021 University of Massachusetts Amherst

Simulating The Effects Of Floating Platforms, Tilted Rotors, And Breaking Waves For Offshore Wind Turbines, Hannah Johlas

Doctoral Dissertations

Offshore wind energy is a rapidly expanding source of renewable energy worldwide, but many aspects of offshore wind turbine behavior are still poorly understood and are not accurately captured by low-cost engineering models used in the design process. To help improve these models, computational fluid dynamics (CFD) can provide valuable insight into the complex fluid flows that affect offshore wind turbine power generation and structural loads. This research uses CFD simulations to examine three main topics important to future offshore wind development: how breaking waves affect structural loads for fixed-bottom wind turbines; how platform motions affect power generation, wake characteristics ...


Numerical Modeling Of Advanced Propulsion Systems, Peetak P. Mitra 2021 University of Massachusetts Amherst

Numerical Modeling Of Advanced Propulsion Systems, Peetak P. Mitra

Doctoral Dissertations

Numerical modeling of advanced propulsion systems such as the Internal Combustion Engine (ICE) is of great interest to the community due to the magnitude of compute/algorithmic challenges. Fuel spray atomization, which determines the rate of fuel-air mixing, is a critical limiting process for the phenomena of combustion within ICEs. Fuel spray atomization has proven to be a formidable challenge for the state-of-the-art numerical models due to its highly transient, multi-scale, and multi-phase nature. Current models for primary atomization employ a high degree of empiricism in the form of model constants. This level of empiricism often reduces the art of ...


Complicating Factors In Hydraulic Jumps: The Effects Of Earth's Rotation, Muveno Pascoal Elias Mucaza 2021 The University of Western Ontario

Complicating Factors In Hydraulic Jumps: The Effects Of Earth's Rotation, Muveno Pascoal Elias Mucaza

Electronic Thesis and Dissertation Repository

Hydraulic jumps at the interface of stratified rotating fluids are studied. The flow is de- fined with continuous density and velocity profiles, with the velocity in each layer changing (upstream shear). The study is conducted in jumps defined by an imposed velocity transition, and jumps developing over a topography.

The numerical simulations conducted showed the qualitative structure of the flow changing in the cross-width direction, as well as the size and amount of turbulence of the jumps. Mixing in these jumps was shown to increase towards the side of the domain where the jumps were larger and more turbulent. The ...


Blade Optimization For Ground Level Low Speed Wind Turbines, Ryan Foster 2021 Kennesaw State University

Blade Optimization For Ground Level Low Speed Wind Turbines, Ryan Foster

Symposium of Student Scholars

Low speed wind turbines can provide inexpensive and clean energy in areas where large scale wind power generation is impractical. The purpose of this research is to explore factors that affect the efficiency of low speed wind turbine blades. The factors that were tested include angle of attack, angle of twist, chord length, average thickness, span, and taper ratio. The goal is to determine a combination of these variables to enable maximum power extraction from a low wind speed source. These blade parameters are optimized for the Southeastern region of the United States. NOAA weather data at ground level are ...


Lifting Flow Over A Cylinder As A Lift System, Kyle Mello 2021 Kennesaw State University

Lifting Flow Over A Cylinder As A Lift System, Kyle Mello

Symposium of Student Scholars

The goal of this project is to conceptually design a lift system consisting of rotating cylinders that may improve certain flight characteristics when compared to conventional wings for a typical two passenger airplane. The functions of flaps, ailerons, lift to weight ratio and structural responses are considered. The cylindrical model is developed within CFD simulation software such that it generates the same lift produced by the wings of a Cessna 172 wings at cruising speed. Incompressible flow theoretical solutions are initially shown to compare favorably with the computational predictions for elementary cylindrical designs.

The rotating cylinder aircraft generates the same ...


Modeling And Design Optimization For Membrane Filters, YiXuan Sun 2021 New Jersey Institute of Technology

Modeling And Design Optimization For Membrane Filters, Yixuan Sun

Dissertations

Membrane filtration is widely used in many applications, ranging from industrial processes to everyday living activities. With growing interest from both industrial and academic sectors in understanding the various types of filtration processes in use, and in improving filter performance, the past few decades have seen significant research activity in this area. Experimental studies can be very valuable, but are expensive and time-consuming, therefore theoretical studies offer potential as a cost-effective and predictive way to improve on current filter designs. In this work, mathematical models, derived from first principles and simplified using asymptotic analysis, are proposed for: (1) pleated membrane ...


Modeling Dewetting, Demixing, And Thermal Effects In Nanoscale Metal Films, Ryan Howard Allaire 2021 New Jersey Institute of Technology

Modeling Dewetting, Demixing, And Thermal Effects In Nanoscale Metal Films, Ryan Howard Allaire

Dissertations

Thin film dynamics, particularly on the nanoscale, is a topic of extensive interest. The process by which thin liquids evolve is far from trivial and can lead to dewetting and drop formation. Understanding this process involves not only resolving the fluid mechanical aspects of the problem, but also requires the coupling of other physical processes, including liquid-solid interactions, thermal transport, and dependence of material parameters on temperature and material composition. The focus of this dissertation is on the mathematical modeling and simulation of nanoscale liquid metal films, which are deposited on thermally conductive substrates, liquefied by laser heating, and subsequently ...


Background Flow Influence On Impulsive Jet-Driven Micro Droplet Dispersal, Vaishak Thiruvenkitam 2021 Embry-Riddle Aeronautical University

Background Flow Influence On Impulsive Jet-Driven Micro Droplet Dispersal, Vaishak Thiruvenkitam

PhD Dissertations and Master's Theses

Accurately predicting the airborne spread of infectious diseases is crucial in controlling the COVID­19 pandemic today. Studies have shown the spread of expiratory droplets depends on ambient thermodynamic conditions and flow properties of the jet emitted by the activity. However, the droplet spread in conditions of background flow is not yet comprehensively understood. This study uses the Eulerian­-Lagrangian model with k−ω turbulence modelling to simulate spread of particles and study the factors affecting it in a closed environment with a background flow. Respiratory activities are modeled as a non-­isothermal jet of air with droplets suspended in ...


Active Control Of Coherent Structures In An Axisymmetric Jet, Michael Marques Goncalves 2021 Embry-Riddle Aeronautical University

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

PhD 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 ...


Extracting Microplastic From Anhydrous Beach Sediment Utilizing Relative Terminal Velocities, Grace Robertson, Jackson Schuler 2021 Embry-Riddle Aeronautical University

Extracting Microplastic From Anhydrous Beach Sediment Utilizing Relative Terminal Velocities, Grace Robertson, Jackson Schuler

Student Works

The primary intent of this research was to investigate and develop a method to extract microplastics from anhydrous beach sediment. Microplastic is found abundantly in coastal sea environments, including aqueous bottom sediment, and beach sediment (Sagawa, Kawaai, & Hinata, 2018). The scope of the microplastic extraction method in this case is limited to strictly the anhydrous beach sediment. The Venturi Effect and Burnoulli’s Principle have been utilized in the design of a nozzle with airflow that has been injected with a sediment and microplastic heterogenous mixture. A nozzle was designed to operate at the specific terminal velocity of sediment such ...


Design And Flight-Path Simulation Of A Dynamic-Soaring Uav, Gladston Joseph 2021 Embry-Riddle Aeronautical University

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

PhD 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 ...


Analysis Of A Non-Equilibrium Vortex Pair As Aircraft Trailing Vortices, Manuel Ayala 2021 Old Dominion University

Analysis Of A Non-Equilibrium Vortex Pair As Aircraft Trailing Vortices, Manuel Ayala

Mechanical & Aerospace Engineering Theses & Dissertations

Shortly after the roll-up evolution of the vortex sheet behind the wings of an aircraft, a coherent counter-rotating vortex pair emerges. Presence of this vortex pair in the downstream of an aircraft, creates unsafe conditions for other aircraft, especially near airport runways. Fundamental knowledge of the physics that govern the formation, duration and dissipation of aircraft wake vortices is desirable in order to improve aircraft operational safety. This study uses non-equilibrium pressure theory to develop an accurate model describing the physical behavior of the vortex pair created by an aircraft in the early to mid-field vortex regime. An isolated aircraft ...


Bibliometric Analysis On Artificial Compressibility Method Based Cfd Simulations, Bhavna Hemraj Joshi Miss, Chandrakant R. Sonawane Dr, Priyambada bada Praharaj Mrs, Anand Kumar Pandey Dr 2021 Symbiosis Institute of Technology, Symbiosis International Deemed University, India

Bibliometric Analysis On Artificial Compressibility Method Based Cfd Simulations, Bhavna Hemraj Joshi Miss, Chandrakant R. Sonawane Dr, Priyambada Bada Praharaj Mrs, Anand Kumar Pandey Dr

Library Philosophy and Practice (e-journal)

This bibliometric analysis in this paper aims to study the quantitative progress done in the artificial compressibility (AC) method-based CFD simulation and analyze its potential in solving incompressible flow simulations in computational fluid dynamics smoothly. The sector of CFD is enhancing more and more maturely due to advancements in computing architecture, numerical methods, and simulation tools. There have been various attempts to solve the pressure-velocity coupling issue in the Navier-Stokes equation. The artificial compressibility method (ACM), as opposed to pressure-correction methods, solves the incompressible equation in a non-segregated manner. With the introduction of the ACM, the system of the equation ...


A Flat Plate Skin Friction Correlation Including Transition, Jaret M. Wedow 2021 California Polytechnic State University, San Luis Obispo

A Flat Plate Skin Friction Correlation Including Transition, Jaret M. Wedow

Master's Theses

Many existing boundary layer models treat transition as a rapid switch from laminar to turbulent flow, with correlations defining properties in each respective region. Natural transition, however, is not always a very spanwise uniform process, with the onset of transition varying somewhat between different streamwise paths of fluid flow. Thus, a spanwise average of natural transition can result in a more gradual, extended transition region than many existing models predict. Modern applications, such as aircraft wings and fuselages, are extremely streamlined and smooth, allowing for natural transition to occur rather than flow tripping to turbulent near the leading edge. Under ...


Perfromance Improvement Of High Bypass Turbofan Engine Through Optimization Of High-Pressure Compressor Blade – A Case Study, Vlad Mandzyuk 2021 Kennesaw State University

Perfromance Improvement Of High Bypass Turbofan Engine Through Optimization Of High-Pressure Compressor Blade – A Case Study, Vlad Mandzyuk

Symposium of Student Scholars

This research determines the relation between the High-Pressure Compressor (HPC) blade characteristics, compressor pressure ratio, and lift-to-drag ratio of a high bypass turbofan engine. Alterations in the HPC blades airfoil, span, chord, taper ratio, twist, aspect ratio, sweep, and angle of incidence are performed and their effect on the engine’s performance is observed. The metrics used to compare engine performance include thrust, specific thrust, exit velocity, fuel/air ratio, power, and efficiency. Parametric cycle analysis and computational fluid dynamics are performed to compare and validate findings. The goal of this study is to optimize the design of HPC to ...


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 ...


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