Double Wall Cooling Of A Full Coverage Effusion Plate With Main Flow Pressure Gradient, Including Internal Impingement Array Cooling,
2019
University of Alabama in Huntsville
Double Wall Cooling Of A Full Coverage Effusion Plate With Main Flow Pressure Gradient, Including Internal Impingement Array Cooling, Sneha R. Vanga, David Ritchie, Austin Click, Zhong Ren, Phil Ligrani, Federico Liberatore, Rajeshriben Patel, Ram Srinivasan, Yin-Hsiang Ho
PRC-Affiliated Research
The present study provides new effusion cooling data for both the surfaces of the fullcoverage effusion cooling plate. For the effusion-cooled surface, presented are spatially resolved distributions of surface adiabatic film cooling effectiveness and surface heat transfer coefficients (measured using transient techniques and infrared thermography). For the impingement-cooled surface, presented are spatially resolved distributions of surface Nusselt numbers (measured using steady-state liquid crystal thermography). To produce this cool-side augmentation, impingement jet arrays at different jet Reynolds numbers, from 2720 to 11,100, are employed. Experimental data are given for a sparse effusion hole array, with spanwise and streamwise impingement hole spacing …
Double Wall Cooling Of A Full Coverage Effusion Plate With Main Flow Pressure Gradient, Including Internal Impingement Array Cooling,
2019
University of Alabama in Huntsville
Double Wall Cooling Of A Full Coverage Effusion Plate With Main Flow Pressure Gradient, Including Internal Impingement Array Cooling, Sneha R. Vanga, David Ritchie, Austin Click, Zhong Ren, Phil Ligrani, Federico Liberatore, Rajeshriben Patel, Ram Srinivasan, Yin-Hsiang Ho
PRC-Affiliated Research
The present study provides new effusion cooling data for both the surfaces of the fullcoverage effusion cooling plate. For the effusion-cooled surface, presented are spatially resolved distributions of surface adiabatic film cooling effectiveness and surface heat transfer coefficients (measured using transient techniques and infrared thermography). For the impingement-cooled surface, presented are spatially resolved distributions of surface Nusselt numbers (measured using steady-state liquid crystal thermography). To produce this cool-side augmentation, impingement jet arrays at different jet Reynolds numbers, from 2720 to 11,100, are employed. Experimental data are given for a sparse effusion hole array, with spanwise and streamwise impingement hole spacing …
Double Wall Cooling Of A Full Coverage Effusion Plate With Main Flow Pressure Gradient, Including Internal Impingement Array Cooling,
2019
University of Alabama in Huntsville
Double Wall Cooling Of A Full Coverage Effusion Plate With Main Flow Pressure Gradient, Including Internal Impingement Array Cooling, Sneha R. Vanga, David Ritchie, Austin Click, Zhong Ren, Phil Ligrani, Federico Liberatore, Rajeshriben Patel, Ram Srinivasan, Yin-Hsiang Ho
PRC-Affiliated Research
The present study provides new effusion cooling data for both the surfaces of the fullcoverage effusion cooling plate. For the effusion-cooled surface, presented are spatially resolved distributions of surface adiabatic film cooling effectiveness and surface heat transfer coefficients (measured using transient techniques and infrared thermography). For the impingement-cooled surface, presented are spatially resolved distributions of surface Nusselt numbers (measured using steady-state liquid crystal thermography). To produce this cool-side augmentation, impingement jet arrays at different jet Reynolds numbers, from 2720 to 11,100, are employed. Experimental data are given for a sparse effusion hole array, with spanwise and streamwise impingement hole spacing …
Autonomous Watercraft Simulation And Programming,
2019
University of Lynchburg
Autonomous Watercraft Simulation And Programming, Nicholas J. Savino
Student Scholar Showcase
Automation of various modes of transportation is thought to make travel more safe and efficient. Over the past several decades, advances to semi-autonomous and autonomous vehicles have led to advanced autopilot systems on planes and boats, and an increasing popularity of self-driving cars. We predicted the motion of an autonomous vehicle using simulations in Python. The simulation models the motion of a small scale watercraft, which can then be built and programmed using an Arduino Microcontroller. We examined different control methods for a simulated rescue craft to reach a target. We also examined the effects of different factors, such as …
Scale Interactions Within A Perturbed Plane Wall Jet,
2019
Embry-Riddle Aeronautical University
Scale Interactions Within A Perturbed Plane Wall Jet, Shibani Bhatt
Doctoral Dissertations and Master's Theses
The current work focuses on exploiting this behavior to manipulate wall turbulence by targeting the large-scales of the flow. In wall turbulence the large-scales of the flow interact with the smaller scales in a non-linear manner including through a process of amplitude and frequency modulation. A plane wall jet (PWJ) is chosen as the model flow field for this work as its unique geometry allows for the controlled introduction of large-scale perturbations through acoustic forcing. The corresponding interactions because of forcing are characterized using single hot-wire measurements. The nearwall response of the PWJ over a range of large-scale forcing showed …
Investigation Of Endwall Vortex Manipulation In High Lift Turbines Caused By Active Endwall Forcing,
2019
Air Force Institute of Technology
Investigation Of Endwall Vortex Manipulation In High Lift Turbines Caused By Active Endwall Forcing, Horatio J. Babcock
Theses and Dissertations
With the increased demand for lighter, more fuel efficient and smaller gas turbine engines, the impetus to reduce the weight and size of the turbine has become apparent. One approach to reduce this weight is to reduce the number of blades in the turbine. However, to maintain power output, each blade must be capable of supporting a greater amount of lift. While several high-lift turbine profiles have been detailed in literature, most of these profiles have increased endwall losses, despite their desirable mid-span characteristics. To mitigate this endwall loss, a number of active and passive flow approaches have been studied …
Tracking Shock Movement On The Surface Of An Oscillating, Straked Semispan Delta Wing,
2019
Air Force Institute of Technology
Tracking Shock Movement On The Surface Of An Oscillating, Straked Semispan Delta Wing, Justin A. Pung
Theses and Dissertations
A recent research effort, sponsored by the Air Force Office of Scientific Research, numerically investigated the unsteady aerodynamic flow field around an oscillating, straked, delta wing. The study was centered on determining the importance of the unsteady aerodynamic forces acting as a driver for a nonlinear motion known as limit cycle oscillations. The current effort focused on creating a computational model to compare to the results of previous tests and modeling efforts and discover new information regarding the onset of LCO. The computational model was constructed using the Cartesian overset capabilities of the CREATE-AV™ fixed wing fluid dynamics solver Kestrel. …
Influence Of Leading Edge Oscillatory Blowing On Time-Accurate Dynamic Store Separation,
2019
Air Force Institute of Technology
Influence Of Leading Edge Oscillatory Blowing On Time-Accurate Dynamic Store Separation, Ryan G. Saunders
Theses and Dissertations
The primary objective of this research is to support the static and dynamic characterization and the time-accurate dynamic load data acquisition of store separation from a cavity with leading edge oscillatory blowing. Developing an understanding of, and potentially controlling, pitch bifurcation of a store release is a motivation for this research. The apparatus and data acquisition system was used in a two-part experiment to collect both static and dynamic testing data in the AFIT low speed wind tunnel in speeds of 60, 100, and 120 mph, from Reynolds numbers varying from 5.5x104 to 4.6x105, depending on reference …
Analytical Models And Control Design Approaches For A 6 Dof Motion Test Apparatus,
2019
Air Force Institute of Technology
Analytical Models And Control Design Approaches For A 6 Dof Motion Test Apparatus, Kyra L. Schmidt
Theses and Dissertations
Wind tunnels play an indispensable role in the process of aircraft design, providing a test bed to produce valuable, accurate data that can be extrapolated to actual flight conditions. Historically, time-averaged data has made up the bulk of wind tunnel research, but modern flight design necessitates the use of dynamic wind tunnel testing to provide time-accurate data for high frequency motion. This research explores the use of a 6 degree of freedom (DOF) motion test apparatus (MTA) in the form of a robotic arm to allow models inside a subsonic wind tunnel to track prescribed trajectories to obtain time-accurate force …
Wall Model Large Eddy Simulation Of A Diffusing Serpentine Inlet Duct,
2019
Air Force Institute of Technology
Wall Model Large Eddy Simulation Of A Diffusing Serpentine Inlet Duct, Ryan J. Thompson
Theses and Dissertations
The modeling focus on serpentine inlet ducts (S-duct), as with any inlet, is to quantify the total pressure recovery and ow distortion after the inlet, which directly impacts the performance of a turbine engine fed by the inlet. Accurate prediction of S-duct ow has yet to be achieved amongst the computational fluid dynamics (CFD) community to improve the reliance on modeling reducing costly testing. While direct numerical simulation of the turbulent ow in an S-duct is too cost prohibitive due to grid scaling with Reynolds number, wall-modeled large eddy simulation (WM-LES) serves as a tractable alternative. US3D, a hypersonic research …
Initial Stage Of Fluid-Structure Interaction Of A Celestial Icosahedron Shaped Vacuum Lighter Than Air Vehicle,
2019
Air Force Institute of Technology
Initial Stage Of Fluid-Structure Interaction Of A Celestial Icosahedron Shaped Vacuum Lighter Than Air Vehicle, Dustin P. Graves
Theses and Dissertations
The analysis of a celestial icosahedron geometry is considered as a potential design for a Vacuum Lighter than Air Vehicle (VLTAV). The goal of the analysis is ultimately to understand the initial fluid-structure interaction of the VLTAV and the surrounding airflow. Up to this point, previous research analyzed the celestial icosahedron VLTAV in relation to withstanding a symmetric sea-level pressure applied to the membrane of the structure. This scenario simulates an internal vacuum being applied in the worst-case atmospheric environmental condition. The next step in analysis is to determine the aerodynamic effects of the geometry. The experimental setup for obtaining …
Sweep And Taper Analysis Of Surfboard Fins Using Computational Fluid Dynamics,
2019
California Polytechnic State University, San Luis Obispo
Sweep And Taper Analysis Of Surfboard Fins Using Computational Fluid Dynamics, Brandon James Baldovin
Master's Theses
The research presented here provides a basis for understanding the hydrodynamics of surfboard fin geometries. While there have been select studies on fins there has been little correlation to the shape of the fin and its corresponding hydrodynamic performance. This research analyzes how changing the planform shape of a surfboard fin effects its performance and flow field. This was done by isolating the taper and sweep distribution of a baseline geometry and varying each parameter individually whilst maintaining a constant span and surface area. The baseline surfboard fin was used as a template in Matlab to generate a set of …
A Higher-Order Method Implemented In An Unstructured Panel Code To Model Linearized Supersonic Flows,
2019
California Polytechnic State University, San Luis Obispo
A Higher-Order Method Implemented In An Unstructured Panel Code To Model Linearized Supersonic Flows, Jake Daniel Davis
Master's Theses
Since their conception in the 1960s, panel codes have remained a critical tool in the design and development of air vehicles. With continued advancement in computational technologies, today's codes are able to solve flow fields around arbitrary bodies more quickly and with higher fidelity than those that preceded them. Panel codes prove most useful during the conceptual design phase of an air vehicle, allowing engineers to iterate designs, and generate full solutions of the flow field around a vehicle in a matter of seconds to minutes instead of hours to days using traditional CFD methods. There have been relatively few …
Investigation Of The Flow Field And Associated Heat Transfer Within An Asymmetrical Leading Edge Jet Impingement Array,
2019
University of Central Florida
Investigation Of The Flow Field And Associated Heat Transfer Within An Asymmetrical Leading Edge Jet Impingement Array, Jorge Torres
Electronic Theses and Dissertations
This thesis investigates the turbulent flow features present in asymmetrical leading edge jet impingement and their effects from a fluid and heat transfer prospective using both numerical and experimental techniques. The jet-centerline plane flow field was quantified experimentally through the non-intrusive experimental method of Particle Image Velocimetry (PIV), while an area average heat transfer was acquired via a traditional copper block method. The numerical element served to investigate how well the Reynolds Averaged Navier-Stokes (RANS) k-? SST turbulence model predicts the flow field and heat transfer within the leading edge and further investigate the results outside of the experimental scope. …
A Multi-Species Single-Led Hazardous Gas Sensor For Commercial Space Applications,
2019
University of Central Florida
A Multi-Species Single-Led Hazardous Gas Sensor For Commercial Space Applications, Akshita Parupalli
Electronic Theses and Dissertations
In the interest of furthering both commercial and government-funded opportunities for deep space exploration, the safety of life and equipment onboard must be absolutely certain. In this regard, the presence of any hazardous gases or combustion events onboard space vehicles must be quickly characterized and detected. Several hazardous gases of interest have absorption features in the mid-infrared range and can be detected with an infrared light source, via the principles of absorption spectroscopy. A non-dispersive infrared (NDIR) sensor that follows these principles has been developed to utilize light-emitting diodes (LEDs) for gas detection and quantification. LEDs contain a particular advantage …
Wake Vortex Pair Formation As An Analog For Dust Devil And Tornado Genesis,
2019
Old Dominion University
Wake Vortex Pair Formation As An Analog For Dust Devil And Tornado Genesis, Robert L. Ash
Mechanical & Aerospace Engineering Faculty Publications
In 1966, meteorologist R.S. Scorer attempted to explain how large-scale oceanic tropical depressions become hurricanes or typhoons. His model was based on the idea that when these large-scale tropical depression structures begin to rotate, mostly due to Coriolis effects, an annular outer portion of that structure changes suddenly to a potential vortex segment, with the same outer radial limit as the low-pressure structure, but with an inner radius that conserves the overall system angular momentum and kinetic energy. By analogy with the "jump" instability describing sudden buckling of a vertical column, this paper shows that his conjecture merits additional consideration. …
Selective Dielectric Barrier Discharge Actuation For Flow Control Of Delta Wings,
2019
University of Alabama in Huntsville
Selective Dielectric Barrier Discharge Actuation For Flow Control Of Delta Wings, Arnab Chatterjee
Summer Community of Scholars Posters (RCEU and HCR Combined Programs)
No abstract provided.
Design And Testing Of A Wind Energy Harnessing System For Forced Convective Drying Of Grain In Low Wind Speed, Warm And Humid Climates,
2019
University of Kentucky
Design And Testing Of A Wind Energy Harnessing System For Forced Convective Drying Of Grain In Low Wind Speed, Warm And Humid Climates, Francis Akumabi Agbali
Theses and Dissertations--Biosystems and Agricultural Engineering
Forced convective drying using a wind turbine mechanically connected to a ventilation fan was hypothesized for low cost and rapid grain drying in developing countries. The idea was tested using an expandable wind turbine blade system with variable pitch, at low wind speeds in a wind tunnel. The design was based on empirical and theoretical models embedded in a graphical user interface (GUI) created to estimate airflow-power requirements for drying ear corn. Output airflow (0.0016 - 0.0052 m3kg-1s-1) increased within the study wind speed range (2.0 - 5.5 m/s). System efficiency peak (8.6%) was …
Hybrid Multi-Objective Optimization Of Left Ventricular Assist Device Outflow Graft Anastomosis Orientation To Minimize Stroke Rate,
2019
University of Central Florida
Hybrid Multi-Objective Optimization Of Left Ventricular Assist Device Outflow Graft Anastomosis Orientation To Minimize Stroke Rate, Blake Lozinski
Electronic Theses and Dissertations
A Left Ventricular Assist Device (LVAD) is a mechanical pump that is utilized as a bridge to transplantation for patients with a Heart Failure (HF) condition. More recently, LVADs have been also used as destination therapy and have provided an increase in the quality of life for patients with HF. However, despite improvements in VAD design and anticoagulation treatment, there remains a significant problem with VAD therapy, namely drive line infection and thromboembolic events leading to stroke. This thesis focuses on a surgical maneuver to address the second of these issues, guided by previous steady flow hemodynamic studies that have …
Numerical Simulation Of Non-Premixed And Premixed Axial Stage Combustor At High Pressure,
2019
University of Central Florida
Numerical Simulation Of Non-Premixed And Premixed Axial Stage Combustor At High Pressure, Tyler Worbington
Electronic Theses and Dissertations
Axial-staged combustors represent an important concept that can be applied to reduce NOx emissions throughout a gas turbine engine. There are four main CFD models presented in this study that describe a highly turbulent jet-in-crossflow (JIC) simulation of partially premixed and non-premixed jets with a constant chamber pressure of 5 atm absolute. The equivalence ratio of the partially premixed jet was held constant at rich conditions with a �������� of 4 while the main stage varied from ��1 and ��2 of 0.575 and 0.73 with an average headend temperature of 1415K and 1545K, respectively. Chemistry was reduced by tabulation of …
