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Full-Text Articles in Engineering
Effects Of Pressure Side Film Cooling Hole Placement And Condition On Surface Heat Transfer Characteristics Of A Transonic Turbine Blade Tip, Hallie Collopy, Phillip M. Ligrani, Hongzhou Xu, Michael Fox
Effects Of Pressure Side Film Cooling Hole Placement And Condition On Surface Heat Transfer Characteristics Of A Transonic Turbine Blade Tip, Hallie Collopy, Phillip M. Ligrani, Hongzhou Xu, Michael Fox
PRC-Affiliated Research
The effects of film cooling hole placement location along the upper pressure side of a transonic squealer are considered. The thermal performance of four different film cooling configurations; B1, B2, B3 and B4, are considered using the University of Alabama in Huntsville's SS/TS/WT (supersonic/transonic/wind tunnel) experimental facility and a simulated turbine blade row using a linear cascade. Surface-varying results are provided for both the squealer blade tip surface, and for the upper pressure side of the squealer blade. These results are given for blowing ratios ranging from 0.42 to 3.20 in the form of spatially-resolved and spatially-averaged adiabatic film cooling …
Development Of A Trailing Edge Flap Using A Compliant Mechanism, Matthew Maybee
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.
Flow And Heat Transfer In Swirl Tubes — A Review, Florian Seibold, Phillip M. Ligrani, Bernhard Weigand
Flow And Heat Transfer In Swirl Tubes — A Review, Florian Seibold, Phillip M. Ligrani, Bernhard Weigand
PRC-Affiliated Research
The development of modern gas turbines for aircraft propulsion and power generation demands ever-increasing efficiency, which can be achieved by rising the turbine inlet temperature. Therefore, turbine components and especially the leading edge of turbine blades are exposed to particular high thermal loads with temperatures that are well above the melting point of the material. As a result, efficient cooling techniques are essential. Swirling flows in cyclone cooling systems are a promising technique for internal turbine blade leading edge cooling since they promise high heat transfer rates in combination with relatively uniform heat transfer distributions. The current paper presents a …
Development Of A Bio-Inspired Artificial Butterfly Vehicle, Thomas Payne Clark
Development Of A Bio-Inspired Artificial Butterfly Vehicle, Thomas Payne Clark
Honors Capstone Projects and Theses
No abstract provided.
Experimental Study Of Turbulent Flow Heat Transfer And Pressure Loss Over Surfaces With Dense Micro-Depth Dimples Under Viscous Sublayer, Peng Zhang, Yu Rao, Phillip M. Ligrani
Experimental Study Of Turbulent Flow Heat Transfer And Pressure Loss Over Surfaces With Dense Micro-Depth Dimples Under Viscous Sublayer, Peng Zhang, Yu Rao, Phillip M. Ligrani
PRC-Affiliated Research
Presented are experimentally-measured heat transfer and pressure loss characteristics for dimpled surfaces, placed along one surface of a channel, with different ratios of dimple depth to channel height δ/H, and for Reynolds numbers ranging from 10,000 to 70,000. With the same relative dimple spacing to dimple print diameter, and the same ratio of dimple depth to dimple print diameter of δ/d = 0.20, experimental results for arrays of spherical indentation dimples with micro depths of δ = 0.6 and 1.0 mm (δ/H = 0.03 and 0.05) are compared with thermal characteristics for arrays of larger dimples with δ = 4.0 …
Flow Structure And Surface Heat Transfer From Numerical Predictions For A Double Wall Effusion Plate With Impingement Jet Array Cooling, Hwabhin Kwon, Phillip M. Ligrani, Sneha Reddy Vanga, Heesung Park
Flow Structure And Surface Heat Transfer From Numerical Predictions For A Double Wall Effusion Plate With Impingement Jet Array Cooling, Hwabhin Kwon, Phillip M. Ligrani, Sneha Reddy Vanga, Heesung Park
PRC-Affiliated Research
To provide additional understanding of double wall cooling arrangements, especially local distributions of flow properties which are responsible for hot-side surface and cold-side surface heat transfer variations, investigated are numerically-simulated distributions of turbulent flow structural characteristics. Also considered are numerically-simulated surface heat transfer characteristics, including comparisons with experimentally-measured distributions. The numerical results are obtained using the ANSYS FLUENT Version 19.1 numerical code, with a k-ω SST turbulence model. The present arrangement includes a full-coverage effusion cooling plate, with coolant initially supplied by an impingement jet array. Considered are the effects of effusion blowing ratio, impingement jet Reynolds number, and streamwise …
Characterization Of Effective Diffusion Within Viscoelastic Fluids With Elastic Instabilities, Valerie Hietsch, Phillip Ligrani, Mengying Su
Characterization Of Effective Diffusion Within Viscoelastic Fluids With Elastic Instabilities, Valerie Hietsch, Phillip Ligrani, Mengying Su
PRC-Affiliated Research
We considered effective diffusion, characterized by magnitudes of effective diffusion coefficients, in order to quantify mass transport due to the onset and development of elastic instabilities. Effective diffusion coefficient magnitudes were determined using different analytic approaches, as they were applied to tracked visualizations of fluorescein dye front variations, as circumferential advection was imposed upon a flow environment produced using a rotating Couette flow arrangement. Effective diffusion coefficient results were provided for a range of flow shear rates, which were produced using different Couette flow rotation speeds and two different flow environment fluid depths. To visualize the flow behavior within the …
Design And Development Of Active Flow Effectors, Konstantinos Kanistras
Design And Development Of Active Flow Effectors, Konstantinos Kanistras
Summer Community of Scholars (RCEU and HCR) Project Proposals
No abstract provided.
Design And Development Of An Online Wind Tunnel, Konstantinos Kanistras
Design And Development Of An Online Wind Tunnel, Konstantinos Kanistras
Summer Community of Scholars (RCEU and HCR) Project Proposals
No abstract provided.
Spatial Coherence Of Low-Frequency Unsteadiness Associated With A Normal Shock Wave, Matthew Cox, Phillip M. Ligrani, Kyle Goethals
Spatial Coherence Of Low-Frequency Unsteadiness Associated With A Normal Shock Wave, Matthew Cox, Phillip M. Ligrani, Kyle Goethals
PRC-Affiliated Research
The present data illustrate a unique analysis approach to explore the physics of shock-wave-flow interactions, based upon correlation and spectral analysis of digitized shadowgraph visualization time-sequence data. As such, demonstration is provided of the use of high resolution, flow visualization data for quantitative correlation and spectral analysis. A shadowgraph system is employed to visualize time-varying, shock wave flow features within the test section of one leg of the transonic/supersonic wind tunnel (which is also referred to as the SS/TS/WT or SuperSonic/TranSonic/WindTunnel), located within the Propulsion Research Center of the University of Alabama in Huntsville. Of interest is a flow field …
Spatial Coherence Of Low-Frequency Unsteadiness Associated With A Normal Shock Wave, Matthew Cox, Phillip M. Ligrani, Kyle Goethals
Spatial Coherence Of Low-Frequency Unsteadiness Associated With A Normal Shock Wave, Matthew Cox, Phillip M. Ligrani, Kyle Goethals
PRC-Affiliated Research
The present data illustrate a unique analysis approach to explore the physics of shock-wave-flow interactions, based upon correlation and spectral analysis of digitized shadowgraph visualization time-sequence data. As such, demonstration is provided of the use of high resolution, flow visualization data for quantitative correlation and spectral analysis. A shadowgraph system is employed to visualize time-varying, shock wave flow features within the test section of one leg of the transonic/supersonic wind tunnel (which is also referred to as the SS/TS/WT or SuperSonic/TranSonic/WindTunnel), located within the Propulsion Research Center of the University of Alabama in Huntsville. Of interest is a flow field …
Simulation Of A Trailing Edge Flap Using A Compliant Mechanism, Sam Blackwell
Simulation Of A Trailing Edge Flap Using A Compliant Mechanism, Sam Blackwell
Summer Community of Scholars Posters (RCEU and HCR Combined Programs)
No abstract provided.
The Use Of Polyvinyldene Fluoride (Pvdf) Films For Pressure Measurement, Patrick Smith
The Use Of Polyvinyldene Fluoride (Pvdf) Films For Pressure Measurement, Patrick Smith
Summer Community of Scholars Posters (RCEU and HCR Combined Programs)
No abstract provided.
Analysis Of Shock Wave Unsteadiness Using Space And Time Correlations Applied To Shadowgraph Flow Visualization Data, Shannon Marko, Phillip M. Ligrani
Analysis Of Shock Wave Unsteadiness Using Space And Time Correlations Applied To Shadowgraph Flow Visualization Data, Shannon Marko, Phillip M. Ligrani
PRC-Affiliated Research
Unsteady flow characteristics of a normal shock wave, a lambda foot, and a separated turbulent boundary layer are investigated within a unique test section with supersonic inlet flow. The supersonic wind tunnel facility, containing this test section, provides a Mach number of approximately 1.54 at the test section entrance. Digitized shadowgraph flow visualization data are employed to visualize shock wave structure within the test section. These data are analyzed to determine shock wave unsteadiness characteristics, including grayscale spectral energy variations with frequency, as well as time and space correlations, which give coherence and time lag properties associated with perturbations associated …
Analysis Of Shock Wave Unsteadiness Using Space And Time Correlations Applied To Shadowgraph Flow Visualization Data, Shannon Marko, Phillip M. Ligrani
Analysis Of Shock Wave Unsteadiness Using Space And Time Correlations Applied To Shadowgraph Flow Visualization Data, Shannon Marko, Phillip M. Ligrani
PRC-Affiliated Research
Unsteady flow characteristics of a normal shock wave, a lambda foot, and a separated turbulent boundary layer are investigated within a unique test section with supersonic inlet flow. The supersonic wind tunnel facility, containing this test section, provides a Mach number of approximately 1.54 at the test section entrance. Digitized shadowgraph flow visualization data are employed to visualize shock wave structure within the test section. These data are analyzed to determine shock wave unsteadiness characteristics, including grayscale spectral energy variations with frequency, as well as time and space correlations, which give coherence and time lag properties associated with perturbations associated …
Analysis Of Shock Wave Unsteadiness Using Space And Time Correlations Applied To Shadowgraph Flow Visualization Data, Shannon Marko, Phillip M. Ligrani
Analysis Of Shock Wave Unsteadiness Using Space And Time Correlations Applied To Shadowgraph Flow Visualization Data, Shannon Marko, Phillip M. Ligrani
PRC-Affiliated Research
Unsteady flow characteristics of a normal shock wave, a lambda foot, and a separated turbulent boundary layer are investigated within a unique test section with supersonic inlet flow. The supersonic wind tunnel facility, containing this test section, provides a Mach number of approximately 1.54 at the test section entrance. Digitized shadowgraph flow visualization data are employed to visualize shock wave structure within the test section. These data are analyzed to determine shock wave unsteadiness characteristics, including grayscale spectral energy variations with frequency, as well as time and space correlations, which give coherence and time lag properties associated with perturbations associated …
Clustering Of Rapidly Settling, Low-Inertia Particle Pairs In Isotropic Turbulence. Part 1. Drift And Diffusion Flux Closures, Sarma L. Rani, Vijay K. Gupta, Donald L. Koch
Clustering Of Rapidly Settling, Low-Inertia Particle Pairs In Isotropic Turbulence. Part 1. Drift And Diffusion Flux Closures, Sarma L. Rani, Vijay K. Gupta, Donald L. Koch
PRC-Affiliated Research
In this two-part study, we present the development and analysis of a stochastic theory for characterizing the relative positions of monodisperse, low-inertia particle pairs that are settling rapidly in homogeneous isotropic turbulence. In the limits of small Stokes number and Froude number such that , closures are developed for the drift and diffusion fluxes in the probability density function (p.d.f.) equation for the pair relative positions. The theory focuses on the relative motion of particle pairs in the dissipation regime of turbulence, i.e. for pair separations smaller than the Kolmogorov length scale. In this regime, the theory approximates the fluid …
Clustering Of Rapidly Settling, Low-Inertia Particle Pairs In Isotropic Turbulence. Part 2. Comparison Of Theory And Dns, Sarma L. Rani, Rohit Dhariwal, Donald L. Koch
Clustering Of Rapidly Settling, Low-Inertia Particle Pairs In Isotropic Turbulence. Part 2. Comparison Of Theory And Dns, Sarma L. Rani, Rohit Dhariwal, Donald L. Koch
PRC-Affiliated Research
Part 1 (Rani et al. J. Fluid Mech. , vol. 871, 2019, pp. 450–476) of this study presented a stochastic theory for the clustering of monodisperse, rapidly settling, low-Stokes-number particle pairs in homogeneous isotropic turbulence. The theory involved the development of closure approximations for the drift and diffusion fluxes in the probability density function (p.d.f.) equation for the pair relative positions $\boldsymbol{r}$ . In this part 2 paper, the theory is quantitatively analysed by comparing its predictions of particle clustering with data from direct numerical simulations (DNS) of isotropic turbulence containing particles settling under gravity. The simulations were performed at …
Clustering Of Rapidly Settling, Low-Inertia Particle Pairs In Isotropic Turbulence. Part 2. Comparison Of Theory And Dns, Sarma L. Rani, Rohit Dhariwal, Donald L. Koch
Clustering Of Rapidly Settling, Low-Inertia Particle Pairs In Isotropic Turbulence. Part 2. Comparison Of Theory And Dns, Sarma L. Rani, Rohit Dhariwal, Donald L. Koch
PRC-Affiliated Research
Part 1 (Rani et al. J. Fluid Mech. , vol. 871, 2019, pp. 450–476) of this study presented a stochastic theory for the clustering of monodisperse, rapidly settling, low-Stokes-number particle pairs in homogeneous isotropic turbulence. The theory involved the development of closure approximations for the drift and diffusion fluxes in the probability density function (p.d.f.) equation for the pair relative positions $\boldsymbol{r}$ . In this part 2 paper, the theory is quantitatively analysed by comparing its predictions of particle clustering with data from direct numerical simulations (DNS) of isotropic turbulence containing particles settling under gravity. The simulations were performed at …
Clustering Of Rapidly Settling, Low-Inertia Particle Pairs In Isotropic Turbulence. Part 1. Drift And Diffusion Flux Closures, Sarma L. Rani, Vijay K. Gupta, Donald L. Koch
Clustering Of Rapidly Settling, Low-Inertia Particle Pairs In Isotropic Turbulence. Part 1. Drift And Diffusion Flux Closures, Sarma L. Rani, Vijay K. Gupta, Donald L. Koch
PRC-Affiliated Research
In this two-part study, we present the development and analysis of a stochastic theory for characterizing the relative positions of monodisperse, low-inertia particle pairs that are settling rapidly in homogeneous isotropic turbulence. In the limits of small Stokes number and Froude number such that , closures are developed for the drift and diffusion fluxes in the probability density function (p.d.f.) equation for the pair relative positions. The theory focuses on the relative motion of particle pairs in the dissipation regime of turbulence, i.e. for pair separations smaller than the Kolmogorov length scale. In this regime, the theory approximates the fluid …
Clustering Of Rapidly Settling, Low-Inertia Particle Pairs In Isotropic Turbulence. Part 2. Comparison Of Theory And Dns, Sarma L. Rani, Rohit Dhariwal, Donald L. Koch
Clustering Of Rapidly Settling, Low-Inertia Particle Pairs In Isotropic Turbulence. Part 2. Comparison Of Theory And Dns, Sarma L. Rani, Rohit Dhariwal, Donald L. Koch
PRC-Affiliated Research
Part 1 (Rani et al. J. Fluid Mech. , vol. 871, 2019, pp. 450–476) of this study presented a stochastic theory for the clustering of monodisperse, rapidly settling, low-Stokes-number particle pairs in homogeneous isotropic turbulence. The theory involved the development of closure approximations for the drift and diffusion fluxes in the probability density function (p.d.f.) equation for the pair relative positions $\boldsymbol{r}$ . In this part 2 paper, the theory is quantitatively analysed by comparing its predictions of particle clustering with data from direct numerical simulations (DNS) of isotropic turbulence containing particles settling under gravity. The simulations were performed at …
Clustering Of Rapidly Settling, Low-Inertia Particle Pairs In Isotropic Turbulence. Part 1. Drift And Diffusion Flux Closures, Sarma L. Rani, Vijay K. Gupta, Donald L. Koch
Clustering Of Rapidly Settling, Low-Inertia Particle Pairs In Isotropic Turbulence. Part 1. Drift And Diffusion Flux Closures, Sarma L. Rani, Vijay K. Gupta, Donald L. Koch
PRC-Affiliated Research
In this two-part study, we present the development and analysis of a stochastic theory for characterizing the relative positions of monodisperse, low-inertia particle pairs that are settling rapidly in homogeneous isotropic turbulence. In the limits of small Stokes number and Froude number such that , closures are developed for the drift and diffusion fluxes in the probability density function (p.d.f.) equation for the pair relative positions. The theory focuses on the relative motion of particle pairs in the dissipation regime of turbulence, i.e. for pair separations smaller than the Kolmogorov length scale. In this regime, the theory approximates the fluid …
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
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, Sneha R. Vanga, David Ritchie, Austin Click, Zhong Ren, Phil Ligrani, Federico Liberatore, Rajeshriben Patel, Ram Srinivasan, Yin-Hsiang Ho
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, Sneha R. Vanga, David Ritchie, Austin Click, Zhong Ren, Phil Ligrani, Federico Liberatore, Rajeshriben Patel, Ram Srinivasan, Yin-Hsiang Ho
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 …
Design And Preliminary Analysis Of A Morphing Flap, Ethan Wiggins
Design And Preliminary Analysis Of A Morphing Flap, Ethan Wiggins
Summer Community of Scholars Posters (RCEU and HCR Combined Programs)
No abstract provided.
Selective Dielectric Barrier Discharge Actuation For Flow Control Of Delta Wings, Arnab Chatterjee
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 Optimization Of Multi-Winglets, Daniel Hearle
Design And Optimization Of Multi-Winglets, Daniel Hearle
Summer Community of Scholars Posters (RCEU and HCR Combined Programs)
No abstract provided.
Design And Development Of An Actuation System For Morphing Flaps, Nate Mcwilliams
Design And Development Of An Actuation System For Morphing Flaps, Nate Mcwilliams
Summer Community of Scholars Posters (RCEU and HCR Combined Programs)
No abstract provided.
Measurement Of Forces On A Flapping Wing Micro Aerial Vehicle, Darnisha Crane
Measurement Of Forces On A Flapping Wing Micro Aerial Vehicle, Darnisha Crane
Research Horizons Day Posters
No abstract provided.