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A Comparative Analysis Of Computer End-User Support In The Air Force And Civilian Organizations, Maureen C. Casey, Douglas A. Kveene Dec 1991

A Comparative Analysis Of Computer End-User Support In The Air Force And Civilian Organizations, Maureen C. Casey, Douglas A. Kveene

Theses and Dissertations

This study compared end-user computing support provided by the Air Force to support provided by civilian organizations with information centers and those without. Factors measured included the end user's demographics, applications used, the effect of computing on perceived confidence, productivity, quality and quantity of output, the importance of various types of support, and satisfaction with the support received from different sources. A survey was administered to 450 Air Force and 265 civilian end users; 416 were returned (response rate of 58.18%). Although there were significant demographic differences between end users, there were no differences in types of support required. Training, …

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Object-Oriented Analysis And Design Of The Saber Wargame, Christine M. Sherry Dec 1991

Object-Oriented Analysis And Design Of The Saber Wargame, Christine M. Sherry

Theses and Dissertations

This thesis presents an object-oriented analysis and design of Saber, a theater-level computerized wargame, for the Air Force Wargaming Center, Maxwell AFB, Alabama. The analysis and design is based on a recently developed conceptual model, and existing land battle, and additional research. This thesis also begins the implementation process. The design was accomplished using an iterative, five step design process. Objects and operations were chosen and then encapsulated in Ada packages. This thesis also makes necessary changes to the land battle as described by the conceptual model and as the result of additional research. Sound software engineering principles were used …

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A Study Of The Adoption And Effectiveness Of Electronic Mail At The Air Force Institute Of Technology, Douglas D. White Dec 1991

A Study Of The Adoption And Effectiveness Of Electronic Mail At The Air Force Institute Of Technology, Douglas D. White

Theses and Dissertations

This research investigated the relationship between the adoption and effectiveness of electronic mail at the Air Force institute of Technology's School of Systems and Logistics (LS). In this research, theories concerning innovation adoption and measurement of system effectiveness are discussed. Survey instruments from both areas were selected, tested, and used to collect data from the LS faculty and staff. Correlation analysis was performed using the data collected. Findings indicate a correlation does exist between the adoption of electronic mail and the effectiveness surrogate measurement, user satisfaction. There was a significantly strong negative correlation between electronic mail complexity and user satisfaction.

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A Delphi Forecast Of 1996 Roles: Air Force Institute Of Technology Information Resource Management Graduates Assigned To Base Level, David O. Block Dec 1991

A Delphi Forecast Of 1996 Roles: Air Force Institute Of Technology Information Resource Management Graduates Assigned To Base Level, David O. Block

Theses and Dissertations

Graduates of the Air Force Institute of Technology's Information Resource Management master's degree program who are subsequently assigned to base-level positions believe their IRM expertise is wasted in base administration roles that preclude the use of their up-to-date technical educations in managing automated information resources. This research forecasts the role AFIT IRM graduates assigned to base-level positions will need to fill by the year 1996. The research further determined what changes are necessary to resolve the perceived differences between current and forecast roles for these graduates. The Delphi survey method of forecasting was selected as an effective method of discovering …

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An Expert System For Measuring, Interpreting, And Managing System Performance Factors For The Work Information Management System, Billy J. C. Irwin Dec 1991

An Expert System For Measuring, Interpreting, And Managing System Performance Factors For The Work Information Management System, Billy J. C. Irwin

Theses and Dissertations

This study develops an expert system for measuring, interpreting, and managing the Wang VS operating system performance factors for the Work Information Management System. The system's performance concerns least known to system administrators are identified. Of these, SHARER buffers and VTOC cache are identified as factors that can significantly impact system performance with little effort. A six step process is used in developing the expert system. Concept maps representing the structure of the Wang VS Disk Input/Output problem domain are provided. The expert system provides information about the system parameters, SHARER buffers and VTOC cache, and recommends main memory allocations. …

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An Analysis Of The Information Requirements Of Conus Based Deputy Commanders For Maintenance, Daniel J. Green Dec 1991

An Analysis Of The Information Requirements Of Conus Based Deputy Commanders For Maintenance, Daniel J. Green

Theses and Dissertations

The purpose of this research was to identify the information requirements of Air Force Deputy Commanders for Maintenance. It had three basic objectives: (1) identify the critical success factors that they monitor on a continuous basis, (2) identify similarities in those requirements for all DGMs and across major commands, and (3) determine if the application of information technology would enhance their decision making. Surveys were sent to all CONUS based Deputy Commanders for Maintenance. The study found that there were nine critical success factors that were used by a majority of all respondents. In addition, nine command-specific critical success factors …

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Relative Utility Of Selected Software Requirement Metrics, James H. Byers Dec 1991

Relative Utility Of Selected Software Requirement Metrics, James H. Byers

Theses and Dissertations

The objective of this study was to determine the relative utility of selected software requirement metrics in assessing the productivity of the software requirements analysis process and the quality of the products of this process. This objective was met by collecting information about the perceptions that practicing software professionals have of the usefulness of various requirement metrics. The study employed a two part methodology. The first part utilized Basili's goal/question/metric paradigm to identify specific goals of the measurement effort and to identify requirement metrics worthy of further investigation. The second part employed a typical research design to gather perceptions that …

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Structured Hypermedia Application Development Model (Shadm): A Structured Model For Technical Documentation Application Design, Peter W. Cassell Dec 1991

Structured Hypermedia Application Development Model (Shadm): A Structured Model For Technical Documentation Application Design, Peter W. Cassell

Theses and Dissertations

This research was conducted to determine how a Royal Australian Air Force technical maintenance publication could be transformed into a task oriented hypermedia application and to develop a model that could be used for future similar transformations. The model was developed following in-depth analysis of the existing USAF F-15E maintenance publication set and validation was conducted using a prototype developed in HyperWriter, a commercial hypermedia product. The prototype model was based around the performance of three maintenance tasks on an aircraft sub-subsystem and incorporated online user access to the necessary support data for task completion. Publication managers, producers, and users …

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Possible Application Of Quality Function Deployment In Software Systems Development In The United States Air Force, Craig R. Lamb Dec 1991

Possible Application Of Quality Function Deployment In Software Systems Development In The United States Air Force, Craig R. Lamb

Theses and Dissertations

The objectives of the thesis were to determine whether the methods of Quality Function Deployment (QFD) could be used in the software development environment within the USAF, and whether or not this area should be researched further. The research was limited to the requirements analysis and definition phase. The different areas of study included a brief review of the structured analysis methodology, a detailed review of the QFD models currently being used in the product industries, a review of how QFD fits into the software development cycle, and specific software modifications to the QFD methodology. A review of some applications …

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Investigative Search Of Quality Historical Software Support Cost Data And Software Support Cost-Related Data, Brent L. Barber Dec 1991

Investigative Search Of Quality Historical Software Support Cost Data And Software Support Cost-Related Data, Brent L. Barber

Theses and Dissertations

The purpose of the study was to determine what software support cost data and software support cost-related data should and can be collected by the Air Force. In addition, the study was to determine how the subject data should be collected. The collection of this data is necessary in order to measure the accuracy and calibration requirements of the software support cost models used by the Air Force. The study found there was no standard set of data items, and no standard procedures in place for the collection of this data. In most cases data were available or easily accessible, …

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A Comparative Study Of Dod And Civilian Hospital Inventory Management Systems, Karen A. Lemay Dec 1991

A Comparative Study Of Dod And Civilian Hospital Inventory Management Systems, Karen A. Lemay

Theses and Dissertations

The purpose of this thesis was to determine if one method of inventory management would standardize procedures and minimize costs for Department of Defense and civilian hospitals. This was accomplished by conducting a comparative analysis of inventory management systems, used at Wright-Patterson Medical Center, Wright-Patterson Air Force Base, Dayton, Ohio; Kettering Medical Center, Kettering, Ohio; and Evans US Army Community Hospital, Ft. Carson, Colorado. The literature review examined various inventory management methods used for both general and hospital specific inventories. The thesis concluded that, although different automated systems were used at the three hospitals studied, the basis of each inventory …

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Improving Royal Australian Air Force Strategic Airlift Planning By Application Of A Computer Based Management Information System, Neil A. Cooper Dec 1991

Improving Royal Australian Air Force Strategic Airlift Planning By Application Of A Computer Based Management Information System, Neil A. Cooper

Theses and Dissertations

The purpose of this research was to propose a MIS to assist RAAF strategic operational airlift planning. The present manual approach suffers deficiencies in flexibility, consistency and timeliness. Airlift planning was first analysed and found to comprise activities of investigation, detailed static planning, implementation and dynamic planning, and review. Planning performance is measured by the effectiveness and efficiency of resulting airlift. Automation of planning functions was investigated, especially the routing and scheduling of airlift. USAF systems, including ADANS, were reviewed and applicability to the RAAF evaluated. Automation of planning functions was investigated, especially the routing and scheduling of airlift. USAF …

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An Approach For The Distance Delivery Of Afit/Ls Resident Degree Curricula, Mark C. Harris Dec 1991

An Approach For The Distance Delivery Of Afit/Ls Resident Degree Curricula, Mark C. Harris

Theses and Dissertations

This research developed an approach for adapting a resident graduate course, offered by the School of Systems and Logistics, for delivery to remote students through distance education resources and techniques. A review of literature-along with personal interviews of professionals from the fields of education, telecommunications, and technology-provided the information for a model of distance education and an assessment of AFIT's existing and near future resources that may be applied to distance delivery of graduate courses. Semantic network construction software was used to organize the information gathered for the distance education model. Key concepts were distilled from the conceptually multi-dimensional semantic …

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An Expert System Advisor For Medical Evaluation Boards, Jerry S. G. Harrington Dec 1991

An Expert System Advisor For Medical Evaluation Boards, Jerry S. G. Harrington

Theses and Dissertations

Expert system technology has proven itself to be able to improve productivity and decision making in a variety of fields of endeavor. The purpose of this study was to determine if an expert system for medical evaluation boards (MEBs) could improve upon the processing of medical evaluation board cases. Research was conducted to develop an expert system and measure the capabilities of the system, both in terms of accuracy and timeliness of case completion of the medical evaluation administrators/clerks who were assisted by the system. The research methodology involved a three - phase approach. The objective of phase one was …

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Effective Design Of Strategic Control Systems For Air Force Information Management: A Program Evaluation, B. Bruce Cowser Dec 1991

Effective Design Of Strategic Control Systems For Air Force Information Management: A Program Evaluation, B. Bruce Cowser

Theses and Dissertations

Strategic planning and implementation and strategic controls offer organizations powerful and essential tools for proactive management. In Information Management (IM), they hold the key to successfully navigating the current turbulent environment. This study was conducted in order to evaluate strategic controls in Air Force Information Management, and to recommend ways to improve them. A model for strategic controls was developed from the literature to serve as a standard for evaluating current programs. Interviews were conducted at three major commands to gather data on the current state of strategic controls. A qualitative analysis methodology was selected, and recommendations include the following …

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Feature Extraction For Pose Estimation. A Comparison Between Synthetic And Real Ir Imagery, Donald J. Willis Dec 1991

Feature Extraction For Pose Estimation. A Comparison Between Synthetic And Real Ir Imagery, Donald J. Willis

Theses and Dissertations

This research addressed the problem of pose estimation of three- dimensional objects given their two-dimensional IR imagery and corresponding synthetic (computer-generated) IR imagery. Features and techniques were investigated to find those which may be extendable from computer models to real- world IR imagery. GTSIG and SCNGEN were used to create the synthetic imagery. Silhouette and outline shape moments were explored as optimum features for the comparison. Employing back-propagation with momentum as the training paradigm, a two-hidden-layer neural network was able to determine the base-plane orientation of the synthetic imagery to within 7.5 degrees with better than 90% accuracy. (No conclusive …

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A Top-Down Performance Analysis Of A Pegasus-Based Space Strike System, Douglas E. Collins Dec 1991

A Top-Down Performance Analysis Of A Pegasus-Based Space Strike System, Douglas E. Collins

Theses and Dissertations

The feasibility of using Pegasus launch vehicle as a conventional weapons platform is examined. Using a top-down approach, the analysis addresses the fundamental question of whether such a system should be considered for development. The measures of effectiveness considered are delivery range, probability of destroying the target, and responsiveness. Each of the measures is assessed at its top-level and analyzed only to the level of detail needed to address the fundamental question. The study indicates that attaining a high probability of destroying the target requires extremely precise control over the burnout conditions and that the system must be on constant …

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Improvement Of The Thermodynamic Model For A Flux-Difference-Splitting Algorithm For The Computation Of High Speed Flows, Mark E. Schieve Dec 1991

Improvement Of The Thermodynamic Model For A Flux-Difference-Splitting Algorithm For The Computation Of High Speed Flows, Mark E. Schieve

Theses and Dissertations

This study modifies the thermodynamic model of a previously existing first-order accurate Flux Difference Splitting (FDS) algorithm for planar, supersonic nozzles. The thermodynamic model is changed from a calorically and thermally perfect gas to a thermally perfect (imperfect) gas, where the flow field is frozen or non-reacting. The frozen flow and imperfect gas assumptions more nearly approximate the real behavior of a fluid in supersonic propulsive nozzles. The modified code can now account for specific heats that vary as a function of temperature. Using curve fittings of JANAF thermochemical data, the code can handle nine gas species, as well, to …

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Investigation Of A Flux-Difference-Splitting Numerical Method In Supersonic Nozzles, Danny P. Allen Dec 1991

Investigation Of A Flux-Difference-Splitting Numerical Method In Supersonic Nozzles, Danny P. Allen

Theses and Dissertations

This research investigated the effects of adding a second-order flux- difference-splitting (FDS) correction term to an existing computer code that is based on a first-order FDS algorithm. It was determined that the second-order algorithm did improve the accuracy of the code for a source flow analysis, but second-order behavior could not be confirmed by the error convergence patterns. It was also discovered that, when tested across an oblique shock wave, the second-order correction terms had minimal influence on the accuracy and shock capturing ability of the first-order accurate FDS method.

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Ground Collision Avoidance Using A Variable Incidence Altitude Measurement System For The A-7 Aircraft, Thomas A. Hartung Dec 1991

Ground Collision Avoidance Using A Variable Incidence Altitude Measurement System For The A-7 Aircraft, Thomas A. Hartung

Theses and Dissertations

This study examines the use of a forward looking sensor in the implementation of an automatic terrain following system. The effect of the incidence angle is studied as well as methodologies to include dynamic motion in the pointing of the sensor beam. The methods examined include fixed angle with respect to the aircraft, dynamics driven by a simple gain, and dynamics directed to gather the terrain information a fixed time interval ahead of the aircraft. Incidence angles of 25, 50, 75, and 90 are examined. The terrain obstacles include a single parabolic hill, a step change is terrain, and a …

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Comparison Of Pointing Control Systems Utilizing Dahl And Coulomb Friction Model Compensation, Whitney J. Hulett Dec 1991

Comparison Of Pointing Control Systems Utilizing Dahl And Coulomb Friction Model Compensation, Whitney J. Hulett

Theses and Dissertations

Bearing friction can be accurately modeled using the Coulomb friction model, provided the bearing is running. In an application where the bearing is rotated only a very small amount, the bearing does not actually rotate. Instead, the bearing undergoes plastic deformation. A nonlinear friction model was developed by P. R. Dahl of the Aerospace Corporation in the late sixties which addresses this region of placticity or compliance zone. Two friction compensation schemes for a single axis position servomechanism were developed and compared in this study. The first compensator was an integral control regulator/estimator which used the Coulomb friction model. The …

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The Use Of A Higher Order Kinematic Relationship On The Analysis Of Cylindrical Composite Panels, Kathleen V. Tighe Dec 1991

The Use Of A Higher Order Kinematic Relationship On The Analysis Of Cylindrical Composite Panels, Kathleen V. Tighe

Theses and Dissertations

An analytical study was performed to determine the critical buckling loads and natural frequencies for composite cylindrical shells, including transverse shear effects and constant through the thickness direct strain εz. A linearized form of Sanders shell equations are derived, including a parabolic transverse shear strain distribution. Higher order laminate constitutive relations are developed. Hamilton's Principle is applied to derive five partial differential equations of motion and the associated boundary conditions, which are then solved using the Galerkin technique. Ply layups of (0/90), (45/-45), and (0/45/-45/90) were investigated under three boundary conditions, simply supported, clamped, and a combination simple- …

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Fatigue Behavior And Failure Mechanisms Of Centrally Notched [0]8 And [0/902]S Silicon Carbide Reinforced Aluminosilicate Glass, William R. Moschelle Dec 1991

Fatigue Behavior And Failure Mechanisms Of Centrally Notched [0]8 And [0/902]S Silicon Carbide Reinforced Aluminosilicate Glass, William R. Moschelle

Theses and Dissertations

Unidirectional and bidirectional notched laminates of silicon carbides/1723 were fatigue tested under tensile-tensile loading with a load ratio of 0.1. The notch, a hole, was determined to have a significant effect on [0]8 specimens. Matrix cracking developed near the theoretical maximum stress concentration points on the hole propagating parallel to the fibers, in the load direction, followed by fiber breakage. [0/902]s specimens were found to be notched insensitive. Damage modes for this lay-up were transverse ply matrix cracking, delamination and fiber breakage in the longitudinal plies which led to specimen failure. Several existing analytical models were …

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Optimization Of Tangential Mass Injection For Minimizing Flow Separation In A Scramjet Inlet, Richard J. Kacik Dec 1991

Optimization Of Tangential Mass Injection For Minimizing Flow Separation In A Scramjet Inlet, Richard J. Kacik

Theses and Dissertations

With the reemergence of interest in air-breathing hypersonic propulsion, scramjet inlet efficiency has become an area of concern. The impingement of the engine cowl shock near the shoulder (expansion corner between forebody and combustor) may cause boundary layer separation which reduces inlet efficiency. Tangential mass injection (TMI) upstream of the shoulder has recently been tested to control this separation but without much parametric evaluation. To resolve this deficiency, a 2-D scramjet inlet model with variable length cowl, and TMI was built and tested in the WL Mach 6 High Reynolds Number Facility. Parameters varied were boundary layer thickness, TMI flow …

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Failure Characterization Of A Fiber Reinforced Ceramic Matrix Composite With Circular Holes, Daniel E. Bullock Dec 1991

Failure Characterization Of A Fiber Reinforced Ceramic Matrix Composite With Circular Holes, Daniel E. Bullock

Theses and Dissertations

The purpose of this study was to investigate the performance of a fiber reinforced ceramic matrix composite with circular holes. The specific objectives were to (1) determine the relationship between tensile failure stress and the ratio of hole diameter to specimen width, and (2) to examine the initiation and progression of damage. The ceramic matrix composite used was SiC/ 1723, composed of continuous silicon titanium carbide fibers in an aluminosilicate glass ceramic matrix. Uniaxial tensile tests were performed at room temperature on two different layups; unidirectional [0]8, and [0/90]2s symmetric. Each layup was tested at three diameter-to-width …

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Thermomechanical Fatigue Characterization Of An Angle Ply Metal Matrix Composite, Wade H. Vaught Dec 1991

Thermomechanical Fatigue Characterization Of An Angle Ply Metal Matrix Composite, Wade H. Vaught

Theses and Dissertations

An investigation was conducted to study the thermomechanical fatigue (TMF) response of a [±45]2s angle ply SCS-6/titanium-15-3 metal matrix composite (MMC). Load controlled in-phase TMF experiments were performed over the temperature range 149-427 C, with a cycle frequency of 0.02 Hz. Test equipment included a high temperature extensometer, quartz lamp radiative heaters controlled by a Micricon thermal control unit and TMF test control software, MATE263. Stress and strain hysteresis, total strain and stiffness were monitored to characterize material behavior. Large plastic deformations were observed in all specimens, with total failure strains ranging from 7 to 13 percent. It was …

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Application Of Finite Element Modeling And Analysis To The Design Of Positive Pressure Oxygen Masks, Bruce H. Bitterman Dec 1991

Application Of Finite Element Modeling And Analysis To The Design Of Positive Pressure Oxygen Masks, Bruce H. Bitterman

Theses and Dissertations

This study investigated tools and techniques for performing finite element analysis of the MBU-20/P pilot's oxygen mask. The problem which was investigated was the fit of the mask to the face at Positive Pressure Breathing (PPB) pressures. Deformed geometry of the mask and reaction forces on the face were calculated to provide a measure of the fit. The MBU-20/P mask was first digitized by 3-D digitizer. A computer program was written to translate the digitized coordinate data to a finite element format for two commercial packages. The packages targeted were SDRC I-DEAS and PDA PATRAN. Other supplementary programs were written …

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A Comparison Of Fractional Order Time Derivative Models Of The Viscoelastic Stress Relations In Thermorheologically Complex Materials, Victor B. Chambers Dec 1991

A Comparison Of Fractional Order Time Derivative Models Of The Viscoelastic Stress Relations In Thermorheologically Complex Materials, Victor B. Chambers

Theses and Dissertations

The purpose of this thesis was to examine the viscoelastic behavior of thermorheologically complex materials, a typical example of which is a soft, rubbery material. Materials such as these are very useful in damping vibrations in structures, but the relaxation moduli of these materials change significantly with temperature and frequency. In the case of space structures applications where temperatures vary greatly and a stable platform is necessary, a method to predict this changing modulus is needed. The original approach was to validate a previously developed viscoelastic model, but the task expanded to include extending the model to materials with two …

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Thermal Nonequilibrium Effects On Turbine Cascade Aerodynamics, Jill L. R. Shaw Dec 1991

Thermal Nonequilibrium Effects On Turbine Cascade Aerodynamics, Jill L. R. Shaw

Theses and Dissertations

The AFIT Total Variation Diminishing Euler Code (ATEC) was modified to include a thermal nonequilibrium model to investigate high temperature effects associated with vibrational relaxation in a transonic turbine cascade. Incorporation of this model into ATEC and creating ANTEC (AFIT Nonequilibrium TVD Euler Code) was accomplished in three steps. Steady-state solutions obtained with ANTEC were compared with those obtained with ATEC for various inlet and exit conditions. The Courant-Friedrichs-Levy criterion was held constant to ATEC; however, it required variation for ANTEC. Blade temperature profiles, temperature difference contours in the vicinity of the trailing edge and the value of the ratio …

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A Comparative Study Of Numerical Versus Analytical Waverider Solutions, Gregory O. Stecklein Dec 1991

A Comparative Study Of Numerical Versus Analytical Waverider Solutions, Gregory O. Stecklein

Theses and Dissertations

The WL/FIMM explicit, Roe flux-splitting Euler algorithm is applied to the inviscid hypersonic flow over a parabolic-top waverider configuration optimized for Mach 10 at zero degrees angle of attack. An on-design grid refinement study is conducted to determine the asymptotic nature of the optimized flight parameter L/D. A parametric study of off-design conditions is conducted to determine flow perturbation effects on HSDT waverider theory. A validation of the Euler code is conducted through a comparison of the numerical data to analytical results derived by Rasmussen. The grid refinement study shows little effect on the inviscid calculation of the optimized parameter …

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