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Total Hemispherical Emittance Of Niobium-1% Zirconium Fuel Cladding For The Sp-100 Space Reactor, John E. Thomason Iii Dec 1992

Total Hemispherical Emittance Of Niobium-1% Zirconium Fuel Cladding For The Sp-100 Space Reactor, John E. Thomason Iii

Theses and Dissertations

Total hemispherical emittance was measured for the SP-100 reactor fuel cladding alloy (Nb-l% Zr). Based on a standard test method (ASTM C 835-82), experiments were conducted on a reference sample of oxidized stainless steel and then on a sample of actual cladding. The sample is heated in a vacuum by passing DC current through it until reaching equilibrium. Measurements are made of the electrical power dissipated in the sample and of the surface temperature. Using the Stefan-Boltzmann Law and some key assumptions concerning conductive and radiative heat transfer, the measured quantities are used to calculate emittance. Calculated values for unoxidized …

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A Two-Stage Intercontinental Ballistic Missile (Icbm) Design Optimization Study And Life Cycle Cost Analysis, David P. Blanks, Douglas M. Bruce, Anthony M. Logue, Ralph A. Sandfry, Stephen J. Skotte, Michael L. Zywien Dec 1992

A Two-Stage Intercontinental Ballistic Missile (Icbm) Design Optimization Study And Life Cycle Cost Analysis, David P. Blanks, Douglas M. Bruce, Anthony M. Logue, Ralph A. Sandfry, Stephen J. Skotte, Michael L. Zywien

Theses and Dissertations

Realities of recent changes in the fiscal environment and the international domestic security structure have caused the strategic community to make some difficult decisions to preserve the capability of the current ICBM force. One of these decisions is to view Minuteman Ill as the centerpiece of the strategic force well into the next century. Extending the life of the 24-year- old Minuteman III system requires system solutions that provide required performance at an affordable life cycle cost. The intent of this study is to demonstrate the feasibility of designing a 2-stage ICBM to perform the Minuteman III mission. The main …

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Integrated Blade Inspection System (Ibis) Upgrade Study, Tony J. Deliberato, Steven W. Perkins, Steven K. Saplin, John G. Snyder, Gregory J. Toussaint Dec 1992

Integrated Blade Inspection System (Ibis) Upgrade Study, Tony J. Deliberato, Steven W. Perkins, Steven K. Saplin, John G. Snyder, Gregory J. Toussaint

Theses and Dissertations

The purpose of this design study was to identify ways to improve the Integrated Blade Inspection System. The Air Force requires inspection of jet engine compressor and turbine blades to locate defects and prevent engine failure. The current inspection process uses fluorescent penetrant as an aid to identify cracked blades. A systems engineering design process was applied to evaluate the current inspection techniques and to develop alternative methods to satisfy the Air Force requirements. Three different inspection systems were developed and compared to the current process: manual, semi-automated, and fully automated inspection. This study made several noteworthy contributions: development of …

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Analysis Of Kriging Applied To Resolution Enhancement Of Digital Satellite Imagery, David J. Blaufuss Dec 1992

Analysis Of Kriging Applied To Resolution Enhancement Of Digital Satellite Imagery, David J. Blaufuss

Theses and Dissertations

To aid the viewer in interpreting the information contained in an image, spatial resolution of the image can be increased. One way to increase the resolution is to improve the optics and sensors of the imaging system. Another is to process the data on the ground by computer. Enhancement techniques can be employed to alter the image and extract necessary data. Current techniques to manipulate and enlarge an image are nearest-neighbor, bilinear interpolation, and cubic convolution which can give greater clarity and readability. To satisfy the growing demand for quality (high-resolution) remotely sensed images, new techniques to enhance images need …

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An Analysis Of Usspacecom's Space Surveillance Network (Ssn) Sensor Tasking Methodology, Jeff M. Berger, Joseph B. Moles, David G. Wisley Dec 1992

An Analysis Of Usspacecom's Space Surveillance Network (Ssn) Sensor Tasking Methodology, Jeff M. Berger, Joseph B. Moles, David G. Wisley

Theses and Dissertations

This study provides the basis for the development of a cost/benefit assessment model to determine the effects of alterations to the Space Surveillance Network (SSN) on orbital element (OE) set accuracy. It provides a review of current methods used by NORAD and the SSN to gather and process observations, an alternative to the current Gabbard classification method, and the development of a model to determine the effects of observation rate and correction interval on OE set accuracy. The proposed classification scheme is based on satellite J2 perturbations. Specifically, classes were established based on mean motion, eccentricity, and inclination Since J2 …

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Analysis Of Whole-Sky Imager Data To Determine The Validity Of Pcflos Models, Richard W. Boltz, George R. Kather Dec 1992

Analysis Of Whole-Sky Imager Data To Determine The Validity Of Pcflos Models, Richard W. Boltz, George R. Kather

Theses and Dissertations

Models used to predict the probability of a cloud-free line-of-sight (PCFLOS) from the ground to space have existed since the 1960s. Unfortunately, an adequate data set has not been available to check the validity of these models until the deployment of the Whole-Sky Imager (WSI) system in 1989. Now that a three-year database has been collected from the WSI system, it is possible to validate, or refute, the existing models. This study investigates the most generally accepted models. Specifically, we investigate three questions: (1) Is the Lund and Shank-lin PCFLOS model assumption of azimuthal independence valid; (2) Does the Lund …

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Analysis Of Titan Iv Launch Responsiveness, Michael T. Dunn Dec 1992

Analysis Of Titan Iv Launch Responsiveness, Michael T. Dunn

Theses and Dissertations

This research investigates the feasibility of developing responsive space systems through responsive launch operations with the Titan IV, the only expendable heavy-lift launch vehicle in the United States inventory. A definition for responsive launch has not been firmly established by Air Force Space Command for this launch vehicle. For benchmark purposes, this study uses the responsive launch definition contained in the proposal request for the Medium Launch Vehicle Ill: launch vehicle ignition within 60 days of mission need notification. Titan IV launch processing at Cape Canaveral Air Force Station (CCAFS), Florida currently requires in excess of six months, rendering Titan …

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Comparison Of Artificial Neural Networks With A Conventional Heuristic Technique For Optimization Problems, Jeffrey S. Gruner Dec 1992

Comparison Of Artificial Neural Networks With A Conventional Heuristic Technique For Optimization Problems, Jeffrey S. Gruner

Theses and Dissertations

This research investigates the utility of the Hopfield and Kohonen artificial neural networks to the traveling salesman optimization problem. A third, non-neural-network technique (the Christofides Algorithm - a competitive, bounded-solution operations research technique) is also investigated for comparison to the artificial neural network solutions. An eight and forty-two city distribution are chosen for comparison of the solutions.

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A Model Of Global Positioning System (Gps) Master Control Station (Mcs) Operations, David N. Koster Dec 1992

A Model Of Global Positioning System (Gps) Master Control Station (Mcs) Operations, David N. Koster

Theses and Dissertations

The United States Air Force's Navstar Global Positioning System (GPS) provides high-accuracy space-based navigation and time distribution to suitably- equipped military and civilian users. The system consists of earth-orbiting satellites and a world-wide network of ground stations. A single operational control center, the GPS Master Control Station (MCS) monitors, maintains, and commands the GPS satellite constellation. The on-going deployment of the complete satellite constellation and recent changes in the operational crew structure may invalidate previously used planning and management paradigms. There is currently no analytical method for predicting the impact of these and other environmental changes on system parameters and …

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Recurrent Neural Networks For Radar Target Identification, Eric T. Kouba Dec 1992

Recurrent Neural Networks For Radar Target Identification, Eric T. Kouba

Theses and Dissertations

A real-time recurrent learning algorithm was applied to a five class radar target identification problem. The wideband radar was assumed to measure both kinematic (tracking information expressed as estimated aspect angles) and high range resolution data from a single, isolated aircraft. The aspect angles (azimuth and elevation) of the aircraft relative to the radar were assumed to be constantly chancing. This created temporal sequences of high range resolution radar signatures that changed as the aspect angles changed. These sequences were used as input features to a recurrent neural network for three radar target identification test cases. The first test case …

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A Toposcopic Investigation Of Brain Electrical Activity Induced By Motion Sickness, Dwight A. Roblyer Dec 1992

A Toposcopic Investigation Of Brain Electrical Activity Induced By Motion Sickness, Dwight A. Roblyer

Theses and Dissertations

A toposcope was constructed as a new tool to study signal frequency and phase relationships in electroencephalogram (EEG) records collected while subjects were experiencing motion sickness. This new tool, named TOPOS, is a software-based, multi-featured version of Grey Walter and Harold Shipton's device which they first produced in the late 1940s. The TOPOS graphical display permits the study of instantaneous frequency relationships between the input channels and a reference signal of fixed or varying frequency. TOPOS adds a correlation grid to aid observers in detecting channel-to-reference correlation levels. Users can also vary several display parameters via menus to optimize the …

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Locating An Imaging Radar In Canada For Identifying Spaceborne Objects, William G. Schick Dec 1992

Locating An Imaging Radar In Canada For Identifying Spaceborne Objects, William G. Schick

Theses and Dissertations

This research presents a study of the maximal coverage p-median facility location problem as applied to the location of an imaging radar in Canada for imaging spaceborne objects. The classical mathematical formulation of the maximal coverage p-median problem is converted into network-flow with side constraint formulations that are developed using a scaled down version of the imaging radar location problem. Two types of network-flow with side constraint formulations are developed: a network using side constraints that simulates the gains in a generalized network; and a network resembling a multi-commodity flow problem that uses side constraints to force flow along identical …

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Retinal Modeling: Segmenting Motion From Spatio-Temporal Inputs Using Neural Networks, David E. Swanson Dec 1992

Retinal Modeling: Segmenting Motion From Spatio-Temporal Inputs Using Neural Networks, David E. Swanson

Theses and Dissertations

We applied two first-order, linear, time-varying, differential equations to the task of segmenting motion from sequences of images. The equations are modified Grossberg formulas for long-term and short-term memory models characterizing the neurotransmitter and cell-activity levels of a synapse and neuron. We described how a two layered, sensory, neural network can be built using the equations to simulate the amacrine neurons of the retina. The model is defined using adaptive input nodes (adaptive model) and is compared to a similar model without these nodes (O and G model). By replicating the basic amacrine neuron model to form both one- and …

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An Assessment Of Software Safety As Applied To The Department Of Defense Software Development Process, Peter W. Colan, Robert W. Prouhet Dec 1992

An Assessment Of Software Safety As Applied To The Department Of Defense Software Development Process, Peter W. Colan, Robert W. Prouhet

Theses and Dissertations

This research analyzed the relationships between the DOD software development process, system safety requirements, and current structured software safety analysis techniques. The current state of software safety was assessed within the aerospace industry and DOD, and a training program for DOD System Safety Managers was developed. A telephone survey was conducted to gather information on current software safety analysis techniques and methodologies. Personal interviews were conducted with Aeronautical System Center System Safety Managers to gather data on job perception and perceived training needs. The results of the study indicate that the DOD guidance and policy documents needed to implement and …

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Software Support Measurement And Estimating For Oracle Database Applications Using Mark Ii Function Points, Steven D. Radnov Dec 1992

Software Support Measurement And Estimating For Oracle Database Applications Using Mark Ii Function Points, Steven D. Radnov

Theses and Dissertations

This study investigated the results of measuring software support of Oracle database applications and estimating the effort and schedule required to provide support. Software measurement was accomplished with a variant of the function points metric, called Mark II function points, which is comprised of three weighted parameters, inputs, entities, and outputs. A technique for mapping Mark II function points to Oracle DBMS components was developed, and the size of the software support for each project, per team, was measured by tabulating and weighting the number of inputs, entities, and outputs that are added, changed, and/or deleted. Software support effort was …

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Development Of A Prototype Air Force Institute Of Technology (Afit) Research Management System (Arms), David N. Schaaf, Carl W. Scott Dec 1992

Development Of A Prototype Air Force Institute Of Technology (Afit) Research Management System (Arms), David N. Schaaf, Carl W. Scott

Theses and Dissertations

The goal of this study was to design, develop, test, and evaluate an initial prototype information system to enhance the conduct and management of research in the School of Systems and Logistics at the Air Force Institute of Technology (AFIT). To accomplish this goal, the researchers developed and completed a methodology that was generally patterned after the milestones in a typical system development life cycle. The proof-of-concept nature of this research caused the researchers to also map the study's seven major objectives into a second system development model called the Spiral Model (Boehm, 1988:61). This hybrid approach provided better defined …

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An Analysis Of The Effectiveness Of Air Force Information Management Officer Training Based On The Perceived Needs Of Current Information Management Officers, David P. Biros, Stewart J. Cole Dec 1992

An Analysis Of The Effectiveness Of Air Force Information Management Officer Training Based On The Perceived Needs Of Current Information Management Officers, David P. Biros, Stewart J. Cole

Theses and Dissertations

The purpose of this study was to determine if the computer orientation courses provided Air Force information managers are properly focused. This study found that the courses have made the desired impact and, with minor exceptions, information managers perceive then-selves to be more knowledgeable after the training. From the results of the survey it is apparent that information managers are more knowledgeable of computers than they were in a study completed in 1988. The officers who attended training after the course was modified to include computer orientation were much more satisfied with their training than previous graduates. They indicated a …

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Staffing Sources Of Usaf Medical Center Systems Offices: A Study Of Their Relation To Information Systems Quality, William K. Dorr, Shelley D. Christia Dec 1992

Staffing Sources Of Usaf Medical Center Systems Offices: A Study Of Their Relation To Information Systems Quality, William K. Dorr, Shelley D. Christia

Theses and Dissertations

This study measured the relationship between Medical Systems Office staffing source (i.e., military medical, military communications/computer, civilian government, and contractor personnel) and quality of automated information services provided at CONUS USAF medical centers. A literature search determined that information system quality is best measured on eight dimensions: performance, features, reliability, conformance, durability, serviceability, aesthetics, and perceived quality. The CIO at each medical center was surveyed to determine the level of system conformance to Air Force standards and to gather data on each MSO staff. Users at the medical centers were also surveyed in order to measure performance, features, reliability, serviceability, …

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Automated Logistics Information Systems: A Case Study, James E. Hogue Dec 1992

Automated Logistics Information Systems: A Case Study, James E. Hogue

Theses and Dissertations

A change within the Air Force has shifted management responsibilities within the logistics community. Formerly diverse functions have come under the purview of a single manager-the Logistics Group Commander-who has inherited information systems that may riot be able to provide consolidated information for informed and accurate decision making. The purpose of this thesis was to describe the current and potential ability for three logistics information management systems to share data: Standard Base Supply System, Consolidated Aircraft Management System, and On-Line Vehicle Information Management System. A systems model was synthesized from the literature review to determine what components of a system …

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Reliability, Maintainability, And Supportability (Rms) Education In Engineering Schools, Gregory T. Hurst, Barry N. Kinter Dec 1992

Reliability, Maintainability, And Supportability (Rms) Education In Engineering Schools, Gregory T. Hurst, Barry N. Kinter

Theses and Dissertations

The purpose of this research is to show how engineering schools, as a whole, perceive the role of reliability, maintainability, and supportability in the engineering field. This includes the degree to which these concepts are included in their curricula, whether industry recruiters look for reliability, maintainability, and supportability training when they visit college campuses and to what degree college faculties are teaching reliability, maintainability, and supportability. This is done through research of existing literature and the analysis of data from a survey completed by engineering schools. General analyses are presented of the overall responses and detailed analysis of contrasts and …

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Integrated Diagnostic Expert System Model (Idesm): A Model For The Conversion Of Fault Isolation Procedures Into An Integrated Diagnostic Expert System, Robert J. Lacey, Glen D. Steemson Dec 1992

Integrated Diagnostic Expert System Model (Idesm): A Model For The Conversion Of Fault Isolation Procedures Into An Integrated Diagnostic Expert System, Robert J. Lacey, Glen D. Steemson

Theses and Dissertations

The purpose of this research was to develop a model to convert existing hardcopy maintenance manual fault isolation procedures into electronic format and to partially automate the fault isolation process. A comprehensive model was developed which comprised four major components: user interface, expert system submodel, hypermedia submodel, and a submodel integration shell. Using this model, the F 15E nose landing gear fault isolation procedures were transformed into a rule based expert system. An existing hypermedia information base was expanded and subsequently integrated with the expert system to form the prototype application. The prototype was evaluated by engineering and maintenance personnel …

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Improving The Quality Of Machine Translations By Providing Stylistic Guidelines To Authors And Editors, Edward J. Walsh Dec 1992

Improving The Quality Of Machine Translations By Providing Stylistic Guidelines To Authors And Editors, Edward J. Walsh

Theses and Dissertations

This research sought to identify stylistic guidelines which could be used by the authors and editors of English language texts in order to improve the quality of subsequent machine translations to other languages. A literature review was conducted to provide background information and to determine what guidelines would be appropriate. Nine guidelines were developed on the basis of the review. The guidelines were then tested. They were applied to five paragraphs from a Royal Australian Air Force technical publication by the researcher and an independent volunteer. Both the resulting texts and the original paragraphs were translated into French using the …

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The Efficacy Of Group Decision Support Systems: A Field Experiment To Evaluate Impacts On Air Force Decision Makers, Benjamin C. Huff Dec 1992

The Efficacy Of Group Decision Support Systems: A Field Experiment To Evaluate Impacts On Air Force Decision Makers, Benjamin C. Huff

Theses and Dissertations

The research contributed to the study of Group Decision Support Systems (GDSS) in field experiments involving real managers making real decisions. This research was conducted by the Air Force Institute of Technology with the Air Force Armstrong Laboratory to evaluate the efficacy of using GDSS technology in an Air Force decision making environment. This study compared facilitated GDSS, facilitated manual, and unfacilitated manual decision making processes. This study focused on performance and secondary outcomes resulting from GDSS effects versus process structure effects. The research evaluated two performance outcomes: GDSS efficiency in terms of decision speed and effectiveness in terms of …

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The Adaptation Of The Sei's Capability Maturity Model To The Air Force Software Acquisition Management Process, William G. Dickerhoff Jr., William J. Sommers Dec 1992

The Adaptation Of The Sei's Capability Maturity Model To The Air Force Software Acquisition Management Process, William G. Dickerhoff Jr., William J. Sommers

Theses and Dissertations

This study develops an Air Force Software Acquisition Maturity Framework (SAMF) by adapting the Software Engineering Institute's (SEI) capability Maturity Model (CMM) to the Air Force software acquisition process. The SAMFs purpose is to provide the Air Force Materiel Command's product centers and program off ices with criterion to assess their software acquisition maturity in a similar fashion as the SEI's CMM provides companies a benchmark to measure their organization's software production maturity. The research was accomplished through a combination of information gathering techniques and data analysis. A literature search of documentation, both within and external to the Department of …

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Collisional Detachment Of Anions Using Fourier Transform Mass Spectrometry, Kevin B. Riehl Dec 1992

Collisional Detachment Of Anions Using Fourier Transform Mass Spectrometry, Kevin B. Riehl

Theses and Dissertations

Fourier Transform Mass Spectrometry (FTMS) is used to make energy resolved ion-neutral reaction measurements at high translational energies (up to several hundred eV). The technique is demonstrated for collisional detachment of anions, and should be easily applied to other inelastic reactions. Collisional detachment cross sections of iodine anions onto gas phase targets of neon, xenon, and trifluoromethyl iodide are measured for 1-300 eV (lab frame). Peak detachment cross sections are roughly 2, 8.5, and 7 Å2, respectively. Ion kinetic measurements show the iodine anion is unreactive in trifluoromethyl iodide at thermal energies. Positive ion chemistry is consistent with …

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Identification Of The Initial Transient In Discrete-Event Simulation Output Using The Kalman Filter, Mark A. Gallagher Dec 1992

Identification Of The Initial Transient In Discrete-Event Simulation Output Using The Kalman Filter, Mark A. Gallagher

Theses and Dissertations

Data truncation is a commonly accepted method of dealing with initialization bias in discrete-event simulation. Algorithms for determining the appropriate initial-data truncation point for univariate and multivariate output are proposed. The techniques entail averaging across replications and estimating a steady-state output model in a state-space framework. Using the estimated model, Multiple Model Adaptive Estimation (MMAE), which uses Kalman filters with different parameter vectors, is applied. Based on the filters' residuals, the conditional probabilities of each filter's specific parameter vector being correct are determined. The MMAE parameter estimates are the probabilistic- weighted average of the filters' assumed parameter vectors. The estimated …

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Regulation Of The Nucleosome-Free Promoter Region Of Simian Virus 40., Dianne Marie Kube Nov 1992

Regulation Of The Nucleosome-Free Promoter Region Of Simian Virus 40., Dianne Marie Kube

Theses and Dissertations

We proposed that SV40 T-antigen binding SiteI and adjacent sequences are involved in the regulation of the proportion of SV40 chromosomes containing a nucleosome-free promoter (NFP) region. Wild-type and SiteI/T antigen defective SV40 chromosomes were analyzed by promoter-specific restriction endonuclease digestion and electron microscopy. SiteI/T antigen mutant chromosomes showed a significant increase in the proportion of chromosomes containing a nuclease hypersensitive promoter region. This increase corresponded to a similar increase in the proportion of chromosomes with a LARGE (greater than 4 times the average internucleosomal distance) nucleosome-free region in the SiteI/T antigen mutants as visualized by electron microscopy. The proportion …

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Working Capital Vs. Cash Flows: A Look At The Changes In Financial Positions A Business Enterprise, Kristina N. Sampson Nov 1992

Working Capital Vs. Cash Flows: A Look At The Changes In Financial Positions A Business Enterprise, Kristina N. Sampson

Theses and Dissertations

No abstract provided.

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Accounting Students And Ethics: Issues Related To Integrating Ethics Into The Accounting Curriculum, Kevin G. Eisenzimmer Nov 1992

Accounting Students And Ethics: Issues Related To Integrating Ethics Into The Accounting Curriculum, Kevin G. Eisenzimmer

Theses and Dissertations

No abstract provided.

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Shock Tube Study Of The Effects Of Large Density Differences And Blowing Ratio On Heat Transfer To A Film-Cooled Flat Plate, Thomas A. Eads Nov 1992

Shock Tube Study Of The Effects Of Large Density Differences And Blowing Ratio On Heat Transfer To A Film-Cooled Flat Plate, Thomas A. Eads

Theses and Dissertations

The effects of coolant-to-mainstream density ratio (D.R.) and mass flux (blowing) ratio (Mb) on flat plate heat transfer were investigated in a shock tube. The round-nosed plate has a single row of holes inclined 35° downstream with two-diameter lateral spacing and hole length of three diameters. Mixing helium with air in the shock tube produced a D.R. range of 1.2 to 2.1. The parameters studied approach those of film-cooled turbine components. For an Mb range of 0.4 to 3 and 10% mainstream turbulence, heat flux was measured with thin-film heat flux gauges located 4 to 30 hole diameters downstream of …

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