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Full-Text Articles in Engineering

Comparisons Of Cooling Performance And Flow Characteristics Of A Combustor Liner Plate With Compound Angle And Simple Angle Effusion Holes, Hwabhin Kwon, Phillip M. Ligrani, Sneha R. Vanga, Heesung Park Mar 2023

Comparisons Of Cooling Performance And Flow Characteristics Of A Combustor Liner Plate With Compound Angle And Simple Angle Effusion Holes, Hwabhin Kwon, Phillip M. Ligrani, Sneha R. Vanga, Heesung Park

PRC-Affiliated Research

The present investigation considers a unique compound angle arrangement, never previously considered, with α = 30°, β = ±30°, such that the compound angle of the effusion holes changes from β = +30° to β = −30°, as adjacent rows of effusion holes are encountered. Also provided are data for comparison from a simple angle configuration with α = 30°, β = 0°. Coolant is supplied to both effusion hole arrays using arrays of impingement cooling jets. The results of the numerical simulations are obtained using the ANSYS FLUENT V 21.1 numerical code, with a shear stress transport (SST) k–ω …


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 Dec 2022

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 …


Feasibility Of Low-Enriched Uranium Fueled Nuclear Thermal Propulsion In The Low-Thrust Region Below 16klbf, Samantha B. Rawlins, Dale L. Thomas Sep 2022

Feasibility Of Low-Enriched Uranium Fueled Nuclear Thermal Propulsion In The Low-Thrust Region Below 16klbf, Samantha B. Rawlins, Dale L. Thomas

PRC-Affiliated Research

No abstract provided.


Flow And Heat Transfer In Swirl Tubes — A Review, Florian Seibold, Phillip M. Ligrani, Bernhard Weigand May 2022

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 …


Effects Of Different Crash Data Variables On Ems Response Time For A Rural County In Alabama, Sneha R. Vanga, Phillip M. Ligrani, Mehrnaz Doustmohammadi, Michael Anderson Apr 2022

Effects Of Different Crash Data Variables On Ems Response Time For A Rural County In Alabama, Sneha R. Vanga, Phillip M. Ligrani, Mehrnaz Doustmohammadi, Michael Anderson

PRC-Affiliated Research

Response time of Emergency Medical Services (EMS) is an important factor related to preventable deaths in road crash incidents. This study focuses on analyzing the effects of different independent variables on the EMS Response Time (ERT). Independent variables considered for this investigation are travel time, day of the week, crash severity, weather, time of the day, and lighting condition. Understanding outcomes resulting from variations of the considered parameters on ERT is crucial to minimize the possibility of adverse outcomes which are tied to different types of injuries, and vital to limit the prospect of fatalities. Crash data used for this …


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 Feb 2022

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 Feb 2022

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 …


Flow And Heat Transfer Characteristics In A Pre-Swirl Rotor-Stator Cavity, Xiaoyu Yang, Zhong Ren, Jing Ren, Philip M. Ligrani Feb 2022

Flow And Heat Transfer Characteristics In A Pre-Swirl Rotor-Stator Cavity, Xiaoyu Yang, Zhong Ren, Jing Ren, Philip M. Ligrani

PRC-Affiliated Research

The present study investigates flow and heat transfer characteristics in a rotor-stator pre-swirl system. Considered are rotational Reynolds numbers ReФ ranging from 3.4 × 105 to 6.8 × 105, with jet Reynolds numbers Rew of approximately 8.8 × 104 to 3.81 × 105, and associated turbulent flow parameter λT = Cw/ReФ0.8 varying from 0 to 0.4. Experimentally-measured and numerically-predicted results illustrate the combined and separate influences of jet impingement and rotor entrainment, as they affect and govern flow and heat transfer characteristics within the cavity. These results show that the relative strength of the two effects varies with ReФ and …


Ems Response Time Analyses For A Rural County Using Geographically Weighted Regression With Different Kernel Weighting Functions, Sneha R. Vanga, Phillip M. Ligrani, Mehrnaz Doustmohammadi, Michael Anderson Jan 2022

Ems Response Time Analyses For A Rural County Using Geographically Weighted Regression With Different Kernel Weighting Functions, Sneha R. Vanga, Phillip M. Ligrani, Mehrnaz Doustmohammadi, Michael Anderson

PRC-Affiliated Research

A Geographically Weighted Regression (GWR) is considered to compare results provided using two different kernel weighting functions: adaptive bi-square kernel and adaptive Gaussian kernel. To provide a baseline reference comparison, resulting data are also considered relative to Global Regression Analysis (GRA) calculations, which are obtained without the inclusion of geographical variability location data. For the analysis, data associated with a total of 214 crash cases for the dates between January 2016 and December 2019 are studied for a rural county in Alabama. Associated crash records are extracted from the Critical Analysis Reporting Environment (CARE) database. Six independent variables, including travel …


Characterization Of Effective Diffusion Within Viscoelastic Fluids With Elastic Instabilities, Valerie Hietsch, Phillip Ligrani, Mengying Su Jan 2022

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 …


Ems Response Time For Patients Critically-Injured From Automobile Accidents Using Regression Analysis, Sneha R. Vanga, Phillip M. Ligrani, Mehrnaz Doustmohammadi, Michael Anderson Sep 2021

Ems Response Time For Patients Critically-Injured From Automobile Accidents Using Regression Analysis, Sneha R. Vanga, Phillip M. Ligrani, Mehrnaz Doustmohammadi, Michael Anderson

PRC-Affiliated Research

The ability to quickly and effectively receive medical treatment in the event of an automobile collision is one of the most important aspects in emergency medical services (EMS). Emergency medical service providers are the first to respond and manage cases related to trauma, emergency surgery, and critically injured patients. Response time for emergency medical services vehicles is especially important for areas, where travel distances are often much larger, compared to more urban areas. The importance of the present data and analysis procedures are their applicability to multiple environments, including urban settings. Methods: The present study is focused on optimization of …


Ems Response Time For Patients Critically-Injured From Automobile Accidents Using Regression Analysis, Sneha R. Vanga, Phillip M. Ligrani, Mehrnaz Doustmohammadi, Michael Anderson Sep 2021

Ems Response Time For Patients Critically-Injured From Automobile Accidents Using Regression Analysis, Sneha R. Vanga, Phillip M. Ligrani, Mehrnaz Doustmohammadi, Michael Anderson

PRC-Affiliated Research

The ability to quickly and effectively receive medical treatment in the event of an automobile collision is one of the most important aspects in emergency medical services (EMS). Emergency medical service providers are the first to respond and manage cases related to trauma, emergency surgery, and critically injured patients. Response time for emergency medical services vehicles is especially important for areas, where travel distances are often much larger, compared to more urban areas. The importance of the present data and analysis procedures are their applicability to multiple environments, including urban settings. Methods: The present study is focused on optimization of …


Small Hall Effect Thruster With 3d Printed Discharge Channel: Design And Thrust Measurements, Ethan P. Hopping, Wensheng Huang, Kunning G. Xu Aug 2021

Small Hall Effect Thruster With 3d Printed Discharge Channel: Design And Thrust Measurements, Ethan P. Hopping, Wensheng Huang, Kunning G. Xu

PRC-Affiliated Research

Citation: Hopping, E.P.; Huang, W.; Xu, K.G. Small Hall Effect Thruster with 3D Printed Discharge Channel: Design and Thrust Measurements. Aerospace 2021, 8, 227. https:// Abstract: This paper presents the design and performance of the UAH-78AM, a low-power small Hall effect thruster. The goal of this work is to assess the feasibility of using low-cost 3D printing to create functioning Hall thrusters, and study how 3D printing can expand the design space. The thruster features a 3D printed discharge channel with embedded propellant distributor. Multiple materials were tested including ABS, ULTEM, and glazed ceramic. Thrust measurements were obtained at the …


Small Hall Effect Thruster With 3d Printed Discharge Channel: Design And Thrust Measurements, Ethan P. Hopping, Wensheng Huang, Kunning G. Xu Aug 2021

Small Hall Effect Thruster With 3d Printed Discharge Channel: Design And Thrust Measurements, Ethan P. Hopping, Wensheng Huang, Kunning G. Xu

PRC-Affiliated Research

Citation: Hopping, E.P.; Huang, W.; Xu, K.G. Small Hall Effect Thruster with 3D Printed Discharge Channel: Design and Thrust Measurements. Aerospace 2021, 8, 227. https:// Abstract: This paper presents the design and performance of the UAH-78AM, a low-power small Hall effect thruster. The goal of this work is to assess the feasibility of using low-cost 3D printing to create functioning Hall thrusters, and study how 3D printing can expand the design space. The thruster features a 3D printed discharge channel with embedded propellant distributor. Multiple materials were tested including ABS, ULTEM, and glazed ceramic. Thrust measurements were obtained at the …


Plasma-Based Water Purification For Crewed Space Missions: Laboratory Experimental Comparisons For On-Board Applicability, Ryan P. Gott, Sydney D. Miller, Josie C. Hodges, Kunning G. Xu Aug 2021

Plasma-Based Water Purification For Crewed Space Missions: Laboratory Experimental Comparisons For On-Board Applicability, Ryan P. Gott, Sydney D. Miller, Josie C. Hodges, Kunning G. Xu

PRC-Affiliated Research

Low-temperature, atmospheric pressure plasma presents a new, inexpensive, and environmentally friendly method of water purification. For long duration crewed space missions, a novel water purification system that does not rely on consumable filters and chemicals would be desirable. Plasma systems provide a viable option for these missions, but their operation and designs need to be optimized and compared to existing technology. For this application, gas and power usage are key limiting factors. In this work, water contaminated with methylene blue is purified with plasma. The rate of purification, gas flow usage, and power consumption are compared for multiple devices. A …


Plasma-Based Water Purification For Crewed Space Missions: Laboratory Experimental Comparisons For On-Board Applicability, Ryan P. Gott, Sydney D. Miller, Josie C. Hodges, Kunning G. Xu Aug 2021

Plasma-Based Water Purification For Crewed Space Missions: Laboratory Experimental Comparisons For On-Board Applicability, Ryan P. Gott, Sydney D. Miller, Josie C. Hodges, Kunning G. Xu

PRC-Affiliated Research

Low-temperature, atmospheric pressure plasma presents a new, inexpensive, and environmentally friendly method of water purification. For long duration crewed space missions, a novel water purification system that does not rely on consumable filters and chemicals would be desirable. Plasma systems provide a viable option for these missions, but their operation and designs need to be optimized and compared to existing technology. For this application, gas and power usage are key limiting factors. In this work, water contaminated with methylene blue is purified with plasma. The rate of purification, gas flow usage, and power consumption are compared for multiple devices. A …


Kinematic Analysis Of Gait In An Underwater Treadmill Using Land-Based Vicon T 40s Motion Capture Cameras Arranged Externally, Shreyas L. Raghu, Ryan T. Conners, Chang-Kwon Kang, David B. Landrum, Paul N. Whitehead Jul 2021

Kinematic Analysis Of Gait In An Underwater Treadmill Using Land-Based Vicon T 40s Motion Capture Cameras Arranged Externally, Shreyas L. Raghu, Ryan T. Conners, Chang-Kwon Kang, David B. Landrum, Paul N. Whitehead

PRC-Affiliated Research

Aquatic therapy for rehabilitation can be performed in a variety of environments, which can vary from a traditional swimming pool to a self-contained underwater treadmill. While kinematic analysis has been performed in large volume swimming pools using specific underwater motion capture systems, researchers may only have access to a land-based motion-capture system, which is not waterproof. Additionally, underwater motion capture systems may not fit within the confines of a smaller underwater treadmill. Thus, the purpose of this study was to design and analyze methodology to quantify lower limb kinematics during an aquatic treadmill session, using a land-based motion capture system. …


Kinematic Analysis Of Gait In An Underwater Treadmill Using Land-Based Vicon T 40s Motion Capture Cameras Arranged Externally, Shreyas L. Raghu, Ryan T. Conners, Chang-Kwon Kang, David B. Landrum, Paul N. Whitehead Jul 2021

Kinematic Analysis Of Gait In An Underwater Treadmill Using Land-Based Vicon T 40s Motion Capture Cameras Arranged Externally, Shreyas L. Raghu, Ryan T. Conners, Chang-Kwon Kang, David B. Landrum, Paul N. Whitehead

PRC-Affiliated Research

Aquatic therapy for rehabilitation can be performed in a variety of environments, which can vary from a traditional swimming pool to a self-contained underwater treadmill. While kinematic analysis has been performed in large volume swimming pools using specific underwater motion capture systems, researchers may only have access to a land-based motion-capture system, which is not waterproof. Additionally, underwater motion capture systems may not fit within the confines of a smaller underwater treadmill. Thus, the purpose of this study was to design and analyze methodology to quantify lower limb kinematics during an aquatic treadmill session, using a land-based motion capture system. …


Kinematic Analysis Of Gait In An Underwater Treadmill Using Land-Based Vicon T 40s Motion Capture Cameras Arranged Externally, Shreyas L. Raghu, Ryan T. Conners, Chang-Kwon Kang, David B. Landrum, Paul N. Whitehead Jun 2021

Kinematic Analysis Of Gait In An Underwater Treadmill Using Land-Based Vicon T 40s Motion Capture Cameras Arranged Externally, Shreyas L. Raghu, Ryan T. Conners, Chang-Kwon Kang, David B. Landrum, Paul N. Whitehead

PRC-Affiliated Research

Aquatic therapy for rehabilitation can be performed in a variety of environments, which can vary from a traditional swimming pool to a self-contained underwater treadmill. While kinematic analysis has been performed in large volume swimming pools using specific underwater motion capture systems, researchers may only have access to a land-based motion-capture system, which is not waterproof. Additionally, underwater motion capture systems may not fit within the confines of a smaller underwater treadmill. Thus, the purpose of this study was to design and analyze methodology to quantify lower limb kinematics during an aquatic treadmill session, using a land-based motion capture system. …


Kinematic Analysis Of Gait In An Underwater Treadmill Using Land-Based Vicon T 40s Motion Capture Cameras Arranged Externally, Shreyas L. Raghu, Ryan T. Conners, Chang-Kwon Kang, David B. Landrum, Paul N. Whitehead Jun 2021

Kinematic Analysis Of Gait In An Underwater Treadmill Using Land-Based Vicon T 40s Motion Capture Cameras Arranged Externally, Shreyas L. Raghu, Ryan T. Conners, Chang-Kwon Kang, David B. Landrum, Paul N. Whitehead

PRC-Affiliated Research

Aquatic therapy for rehabilitation can be performed in a variety of environments, which can vary from a traditional swimming pool to a self-contained underwater treadmill. While kinematic analysis has been performed in large volume swimming pools using specific underwater motion capture systems, researchers may only have access to a land-based motion-capture system, which is not waterproof. Additionally, underwater motion capture systems may not fit within the confines of a smaller underwater treadmill. Thus, the purpose of this study was to design and analyze methodology to quantify lower limb kinematics during an aquatic treadmill session, using a land-based motion capture system. …


Thermochemistry Of Combustion In Polyvinyl Alcohol + Hydroxylammonium Nitrate, James K. Baird, Robert A. Frederick Jr. May 2021

Thermochemistry Of Combustion In Polyvinyl Alcohol + Hydroxylammonium Nitrate, James K. Baird, Robert A. Frederick Jr.

PRC-Affiliated Research

A mixture of polyvinyl alcohol (PVA) and hydroxylammoniun nitrate (HAN) forms a gummy solid known as a plastisol, which is ionically conducting. When an electrostatic potential of 200 V DC is applied across the plastisol, it ignites. Combustion ceases upon removal of the applied voltage. The products of PVA + HAN combustion are known to include the molecular gases carbon monoxide, carbon dioxide, water, nitrogen, and hydrogen. When the electric field within the plastisol is spatially uniform, combustion occurs preferentially at the anode. The fact that HAN is an ionic conductor suggests that the mechanism of combustion is electrolytic in …


Thermochemistry Of Combustion In Polyvinyl Alcohol + Hydroxylammonium Nitrate, James K. Baird, Robert A. Frederick Jr. May 2021

Thermochemistry Of Combustion In Polyvinyl Alcohol + Hydroxylammonium Nitrate, James K. Baird, Robert A. Frederick Jr.

PRC-Affiliated Research

A mixture of polyvinyl alcohol (PVA) and hydroxylammoniun nitrate (HAN) forms a gummy solid known as a plastisol, which is ionically conducting. When an electrostatic potential of 200 V DC is applied across the plastisol, it ignites. Combustion ceases upon removal of the applied voltage. The products of PVA + HAN combustion are known to include the molecular gases carbon monoxide, carbon dioxide, water, nitrogen, and hydrogen. When the electric field within the plastisol is spatially uniform, combustion occurs preferentially at the anode. The fact that HAN is an ionic conductor suggests that the mechanism of combustion is electrolytic in …


Spatial Coherence Of Low-Frequency Unsteadiness Associated With A Normal Shock Wave, Matthew Cox, Phillip M. Ligrani, Kyle Goethals May 2021

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 May 2021

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 …


Highly Branched Polymers Based On Poly(Amino Acid)S For Biomedical Application, Marisa Thompson, Carmen Scholz Apr 2021

Highly Branched Polymers Based On Poly(Amino Acid)S For Biomedical Application, Marisa Thompson, Carmen Scholz

PRC-Affiliated Research

Polymers consisting of amino acid building blocks continue to receive consideration for biomedical applications. Since poly(amino acid)s are built from natural amino acids, the same building blocks proteins are made of, they are biocompatible, biodegradable and their degradation products are metabolizable. Some amino acids display a unique asymmetrical AB2 structure, which facilitates their ability to form branched structures. This review compares the three forms of highly branched polymeric structures: structurally highly organized dendrimers, dendrigrafts and the less organized, but readily synthesizable hyperbranched polymers. Their syntheses are reviewed and compared, methods of synthesis modulations are considered and variations on their traditional …


Highly Branched Polymers Based On Poly(Amino Acid)S For Biomedical Application, Marisa Thompson, Carmen Scholz Apr 2021

Highly Branched Polymers Based On Poly(Amino Acid)S For Biomedical Application, Marisa Thompson, Carmen Scholz

PRC-Affiliated Research

Polymers consisting of amino acid building blocks continue to receive consideration for biomedical applications. Since poly(amino acid)s are built from natural amino acids, the same building blocks proteins are made of, they are biocompatible, biodegradable and their degradation products are metabolizable. Some amino acids display a unique asymmetrical AB2 structure, which facilitates their ability to form branched structures. This review compares the three forms of highly branched polymeric structures: structurally highly organized dendrimers, dendrigrafts and the less organized, but readily synthesizable hyperbranched polymers. Their syntheses are reviewed and compared, methods of synthesis modulations are considered and variations on their traditional …


Louver And Effusion Cooling Heat Transfer For A Double Wall Effusion Plate With Impingement Jet Array Coolant Supply, Sneha Reddy Vanga, Phillip M. Ligrani, Joseph Knox, Federico Liberatore, Rajeshriben Patel, Ying-Hsiang Ho Apr 2021

Louver And Effusion Cooling Heat Transfer For A Double Wall Effusion Plate With Impingement Jet Array Coolant Supply, Sneha Reddy Vanga, Phillip M. Ligrani, Joseph Knox, Federico Liberatore, Rajeshriben Patel, Ying-Hsiang Ho

PRC-Affiliated Research

Louver slot cooling is employed, which consists of an aligned collection of film cooling holes, contained within a specially-designed device which concentrates, and directs the coolant from a slot, so that cooling air then advects as a layer downstream along the test surface. This louver-supplied coolant is then supplemented by coolant which emerges from different rows of downstream film cooling holes. Coolant for both cooling arrangements is supplied using an array of impingement jets. Experimental data are provided for a mainstream Reynolds number Rems range of 168,000–181,000. Full-coverage film cooling initial blowing ratio values are 2.5, 3.2, 4.4, and 5.2, …


Determination Of The Feature Resolution Of Processed Image Data Via Statistical Analysis, Joseph S. Indeck, Jesus O. Mares Jr., James P. Vitarelli, Kavan Hazeli Apr 2021

Determination Of The Feature Resolution Of Processed Image Data Via Statistical Analysis, Joseph S. Indeck, Jesus O. Mares Jr., James P. Vitarelli, Kavan Hazeli

PRC-Affiliated Research

A method is presented to determine the feature resolution of physically relevant metrics of data obtained from segmented image sets. The presented method determines the best-fit distribution curve of a dataset by analyzing a truncated portion of the data. An effective resolvable size for the metric of interest is established when including parts of the truncated dataset results in exceeding a specified error tolerance. As such, this method allows for the determination of the feature resolution regardless of the processing parameters or imaging instrumentation. Additionally, the number of missing objects that exist below the resolution of the instrumentation may be …


Louver And Effusion Cooling Heat Transfer For A Double Wall Effusion Plate With Impingement Jet Array Coolant Supply, Sneha Reddy Vanga, Phillip M. Ligrani, Joseph Knox, Federico Liberatore, Rajeshriben Patel, Ying-Hsiang Ho Apr 2021

Louver And Effusion Cooling Heat Transfer For A Double Wall Effusion Plate With Impingement Jet Array Coolant Supply, Sneha Reddy Vanga, Phillip M. Ligrani, Joseph Knox, Federico Liberatore, Rajeshriben Patel, Ying-Hsiang Ho

PRC-Affiliated Research

Louver slot cooling is employed, which consists of an aligned collection of film cooling holes, contained within a specially-designed device which concentrates, and directs the coolant from a slot, so that cooling air then advects as a layer downstream along the test surface. This louver-supplied coolant is then supplemented by coolant which emerges from different rows of downstream film cooling holes. Coolant for both cooling arrangements is supplied using an array of impingement jets. Experimental data are provided for a mainstream Reynolds number Rems range of 168,000–181,000. Full-coverage film cooling initial blowing ratio values are 2.5, 3.2, 4.4, and 5.2, …


Determination Of The Feature Resolution Of Processed Image Data Via Statistical Analysis, Joseph S. Indeck, Jesus O. Mares Jr., James P. Vitarelli, Kavan Hazeli Apr 2021

Determination Of The Feature Resolution Of Processed Image Data Via Statistical Analysis, Joseph S. Indeck, Jesus O. Mares Jr., James P. Vitarelli, Kavan Hazeli

PRC-Affiliated Research

A method is presented to determine the feature resolution of physically relevant metrics of data obtained from segmented image sets. The presented method determines the best-fit distribution curve of a dataset by analyzing a truncated portion of the data. An effective resolvable size for the metric of interest is established when including parts of the truncated dataset results in exceeding a specified error tolerance. As such, this method allows for the determination of the feature resolution regardless of the processing parameters or imaging instrumentation. Additionally, the number of missing objects that exist below the resolution of the instrumentation may be …