| FOD (Foreign Object Damage) Generation by Aircraft Tires |
AUG 1983 |
247 pages |
| Authors:
Stephan J. Bless; L. Cross; A. J. Piekutowski; H. F. Swift; DAYTON UNIV OH RESEARCH INST
|
 | Lofting of loose debris by overrolling tires was investigated by experiments and analysis. Trajectories of lofted particles were determined with a stereoscopic camera system. Tire speeds ranged up to 40 mph; single-and dual- wheel carriages were used. Debris was mostly stones, 1 inch and smaller. Concrete and packed dirt surfaces, both wet and dry, were included. The probability of lofting a stone, given an encounter, was typically 15 percent, until ... |
|
| High Strain Rate Characterization of Materials |
AUG 1983 |
105 pages |
| Authors:
Stephen J. Bless; A. M. Rajendran; Dave Dawicke; Dennis L. Paisley; DAYTON UNIV OH RESEARCH INST
|
| New techniques have been developed to study dynamic tensile failure of ductile metals: expanding rings, and necked Hopkinson bar samples. Flat plate (spall) experiments have also been carried out. Results are presented for OFHC copper and some other metals. |
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| Development of an Interactive Computer Program to Produce Body Description Data |
JUL 1983 |
74 pages |
| Authors:
L. Douglas Baughman; DAYTON UNIV OH RESEARCH INST
|
| This report documents program GEBOD (GEnerator of BODy data) an interactive computer program which produces the body description portion of the ATB (Articulated Total Body) Model input deck. The ATB Model simulates the motion and dynamic properties of the human body during events such as aircraft flight seat ejection and automobile crashes. This simulation requires the mass, center of gravity location, contact surface dimensions, joint locations, principal moments of inertia ... |
|
| Model Compound Studies of Rigid Rod Aromatic Heterocyclic Polymer Systems, the X-Ray Crystal Structure of 2,6-Diphenylbenzo (1,2-d; 5,4-d') Diimidazole Tetrahydrate, C2OH14N4. 4H2O, a Model System for the Study of Polymer-Water Interaction in Polybenzimid |
JUL 1983 |
|
| Authors:
M. Hunsaker; W. W. Adams; A. V. Fratini; DAYTON UNIV OH RESEARCH INST
|
 | The crystal and molecular structure of 2,6-diphenylbenzo (1,2-d;5,4- d') diimidazole tetrahydrate, C2OH14N4. 4H2O, is determined by single crystal x- ray diffraction. The benzodiimidazole compound is used as a model compound for poly(p-phenylenebenzodiimidazole), a rigid rod polymer. The crystals grown from ethanol are well formed, translucent, and amber tinted. The space group is P21/c (monoclinic), with cell constants a = 9.008(2)A, b = 24.967(7)Angstroms, c = 9. 870(5)Angstroms, Beta = 119.82(3)deg. ... |
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| ATMC (Advanced Technology - Multi-media Communications), The Multi-Media Teleconferencing System |
JUN 1983 |
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| Authors:
Clifford J. Hoffman; William A. McKinney; DAYTON UNIV OH RESEARCH INST
|
| The ATMC (Advanced Technology - Multi-media Communications), teleconferencing systems being developed by the University of Dayton Research Institute (URDI) under the sponsorship of the U.S. Air Force Human Resources Laboratory is designed to provide quality real-time teleconferencing over the switched telephone network. Color business graphics, freeze-frame video, cursor pointing, electronic handwriting, and data communications are integrated into a single highly modularized system to provide superior quality presentation support. (Author) ... |
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| Alternate T-38 Transparency Development. Part 4. Parametric Studies |
JUN 1983 |
|
| Authors:
Richard A. Nash; Blaine S. West; DAYTON UNIV OH RESEARCH INST
|
| Studies conducted to examine the effect of structural parameter variations on the nonlinear, dynamic response of the T-38 student windshield/ support structure system to bird impact are described. The studies were conducted using the materially and geometrically nonlinear analysis (MAGNA) finite element computer program. Both static and transient dynamic analyses were conducted, examining the effects of changes to the transparency and support structure stiffness, intensity of the applied load both ... |
|
| Laser Diagnostic Development and Measurement and Modeling of Turbulent Flowfields of Jets and Wakes. Part 1. Two-Dimensional Laser Doppler Anemometer Studies of Isothermal Flowfield in a Ducted Centerbody Combustor |
JUN 1983 |
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| Authors:
A. J. Lightman; P. D. Magill; R. J. Andrews; DAYTON UNIV OH RESEARCH INST
|
| A two-dimensional laser Doppler anemometer was designed to take measurements in a ducted coaxial flow system having a centerbody separating the jets. The measurements, made in isothermal flow, can be categorized as: central jet only (C02); annular jet only (air); and, combined central and annular jet flow. Radial profiles of the axial and radial/azimuthal velocity were obtained. The central jet only condition approximates a free jet since the central jet ... |
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| Laser Diagnostic Development and Measurement and Modeling of Turbulent Flowfields of Jets and Wakes. Part 2. Numerical Predictions of Isothermal Flowfields in a Ducted Centerbody Combustor |
JUN 1983 |
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| Authors:
L. Krishnamurthy; S. O. Park; D. J. Wahrer; H. S. Cochran; DAYTON UNIV OH RESEARCH INST
|
| Finite-difference numerical computations are presented to predict the isothermal, turbulent, recirculating flowfields in a centerbody combustor configuration which involves confined dual coaxial jet mixing in the near-wake region of an axisymmetric bluff body. Calculations based upon the Reynolds- averaged Navier-Stokes equations and the k-epsilon turbulence model consider the influence of the annular and central flow rates on the nature of the flowfield downstream of the bluff body. The reported isothermal ... |
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| Laser Diagnostic Development and Measurement and Modeling of Turbulent Flowfields of Jets and Wakes. Part 3. The Development of a Two-Channel CW Time- Resolved Laser Raman Spectroscopy (TiLaRS) System for Measurements in Gas Flowfields |
JUN 1983 |
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| Authors:
P. P. Yaney; R. J. Becker; P. T. Danset; M. R. Gallis; DAYTON UNIV OH RESEARCH INST
|
| The design and performance of a photon counting, two-channel spectroscopic system using the 6-W, 448-nm line of a cw argon ion laser is described. The two channels are formed by use of cylindrical optics and special slit mirrors set up following the exit slit of a conventional double spectrometer. The system is capable of dynamic, simultaneous measurements of either the concentrations of two gas species in cold flow or the ... |
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| Proceedings of Workshop to Standardize Atmospheric Measurements in Support of Electro-Optical Systems. |
JUN 1983 |
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| Authors:
Paul J. Huffman; James K. Luers; Nicholas A. Engler; James E. Felt; DAYTON UNIV OH RESEARCH INST
|
| Weapon and surveillance systems operating at visible and infrared wavelengths are rapidly being deployed by the Armed Forces. The performance of these systems is limited by atmospheric conditions. The performance is being evaluated - and will continue to be evaluated - at the several United States test ranges under a variety of atmospheric conditions. Since each of these evaluations uses extensive resources, it is important that each evaluation program be ... |
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| Effect of Through-the-Thickness Stress Distribution upon Crack Growth Behavior in a Nickel-Base Superalloy |
MAY 83 |
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| Authors:
N. E. Ashbaugh; DAYTON UNIV OH RESEARCH INST
|
| Crack growth behavior was investigated in a nickel-base superalloy (IN100) at 732 C in laboratory air under sustained load. The tests were conducted on side-grooved compact-type specimens. One of the purposes of the study was to evaluate the effect of the through-the-thickness stress distribution upon crack growth behavior in grooved specimens. Also in this study the effects of crack orientation and net thickness between the side grooves were evaluated. The ... |
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| Visual Scene Simulation Requirements for C-5A/C-141B Aerial Refueling Part Task Trainer |
MAY 1983 |
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| Authors:
Alfred T. Lee; I. Gavin Lidderdale; DAYTON UNIV OH RESEARCH INST
|
| This report addresses the requirements of visual scene simulation for effective training in a ground-based air refueling part task trainer (ARPTT) to be used by Military Airlift Command (MAC) for C-5A and C-141B aircrew continuation training. Although effective training has been demonstrated in other ARPTTs for initial qualification pilots, it is unclear what this implies for continuation training. Given the reliance of the experienced pilot on a variety of tanker ... |
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| Tolerance Limits and Mechanisms of Failure of the Skeletal System under Impact Conditions |
MAY 1983 |
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| Authors:
G. A. Graves; A. A. Wolff; DAYTON UNIV OH RESEARCH INST
|
| This report is a summary of a statistical analysis of data obtained in several related studies on the mechanical, chemical, and histological properties of primate long bones before and after total body immobilization in plaster casts. Statistical correlations and their significance were determined for more than 60 mechanical, chemical, and histological bone parameters. The parameters were evaluated on primates (rhesus) consisting of control, immobilized, immobilized and exercised, and immobilized and ... |
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| Stability of a Pair of Stationary Vortices in the Leeward Side of a Cylinder in a Potential Flowfield |
MAY 1983 |
|
| Authors:
Shiva N. Singh; DAYTON UNIV OH RESEARCH INST
|
| In this report the steady state flow of an incompressible inviscid fluid past a circular cylinder is considered when a pair of asymmetrical stationary vortices are situated in the rear of the cylinder. Complex potential for this flow is obtained with the help of Milne-Thompson's circle theorem. The condition that the vortex centers have zero induced velocity determines the positions of the stationary vortices. This condition is determined for the ... |
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| Rotational-Vibrational Level Relaxation Effects on Laser-Induced Fluorescence Number Density Mesurements of Hydroxide in a Combustion Environment. I. Effects on Rotational Level Populations. |
MAY 1983 |
|
| Authors:
D. H. Campbell; DAYTON UNIV OH RESEARCH INST
|
| A full vibrational-rotational level rate equation model has been used to investigate the application of laser-induced fluorescence techniques to number density measurements of hydroxide in a combustion environment. The extent of deviation from the simple two-level model, due to rotational relaxation in the upper electronic state and quenching to lower-state vibrational bath levels, was investigated for a range of pressures, temperatures, and laser powers. Time resolved spectral measurements and high ... |
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| Spectrometer Sensitivity Investigations on the Spectrometric Oil Analysis Program |
22 APR 1983 |
|
| Authors:
Wendell E. Rhine; Costandy S. Saba; Robert E. Kauffman; DAYTON UNIV OH RESEARCH INST
|
| An investigation was conducted in order to determine the particle detection capabilities of the A/E35U-3 rotating disk electrode arc/spark emission spectrometer used by the Joint Oil Analysis Program. It was found that the analyses determined with the rotating disk electrode (RDE) spectrometer were particle-size dependent and that the RDE spectrometer cannot quantitatively analyze particles larger than 5-10 micrometers. The reasons for the low particle detection capabilities were examined and found ... |
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| Computer Programs for Producing Single-Event Aircraft Noise Data for Specific Engine Power and Meteorological Conditions for Use with USAF (United States Air Force) Community Noise Model (NOISEMAP) |
APR 1983 |
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| Authors:
Henry T. Mohlman; DAYTON UNIV OH RESEARCH INST
|
| The Air Force community noise prediction model (NOISEMAP) is used to describe the aircraft noise exposure around airbases and thereby aid airbase planners to minimize exposure and prevent community encroachment which could limit mission effectiveness of the installation. This report documents two computer programs (OMEGA 10 and OMEGA 11) which were developed to prepare aircraft flight and ground runup noise data for input to NOISEMAP. OMEGA 10 is for flight ... |
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| Asymptotic Far Field Conditions for Unsteady Subsonic and Transonic Flows |
APR 1983 |
|
| Authors:
Karl G. Guderley; DAYTON UNIV OH RESEARCH INST
|
| Far field conditions for unsteady flow at subsonic and transonic Mach numbers are derived under the assumption that the changes that occur in the flow field are not too slow. One then can derive far field conditions from analytic expressions which approximate the behaviour of wave fronts and sound rays at large distances. In subsonic blows, one uses for this purpose equations linearized for the vicinity of a parallel flow ... |
|
| Rain Erosion Mechanisms of Fluoroelastomer and Polyurethane Coatings on Selected Composite Substrates |
APR 1983 |
76 pages |
| Authors:
Charles J. Hurley; Joseph Zahavi; George F. Schmitt; DAYTON UNIV OH RESEARCH INST
|
| This report documents a test program which was conducted to evaluate the rain erosion resistance of selected coated composite materials at 30 degrees and 90 degrees impact angles in a 1 inch/hour rainfall at 500 mph. Tests included: weight loss, percent coating removal, and SEM examinations. |
|
| Spectrum Fatigue Crack Growth Rate Characteristics of PM (Powder Metallurgy) Aluminums 7090 and 7091 |
APR 1983 |
38 pages |
| Authors:
John J. Ruschau; DAYTON UNIV OH RESEARCH INST
|
| Fatigue crack growth rate testing was performed on powder-metallurgy (PM) produced aluminum 7090 and 7091. Forms examined for each alloy were plate, extrusions, and hand forgings. Crack growth properties for each material were evaluated using both a fighter aircraft-type spectrum (FALSTAFF) and a transport-type aircraft spectrum (Mini-TWIST). All results are compared to ingot-metallurgy (IM) produced aluminum 7050-T76 plate. Results under spectrum loading conditions indicate the PM 7091 alloys are consistently ... |
|
| Measurement and Theory of the Hall Scattering Factor and the Conductivity Mobility in Ultra Pure p-Type Silicon at Low Temperatures |
APR 1983 |
|
| Authors:
Frank Szmulowicz; W. Mitchel; Frank L. Madarasz; Patrick M. Hemenger; DAYTON UNIV OH RESEARCH INST
|
| Acoustic phonon-limited conductivity and Hall mobilities for p-type silicon and germanium have been calculated from solutions of the full Boltzmann equation without the relaxation time approximation. These quantities have been measured as well for p-type silicon in the temperature range 20-50K. Using the deformation potential scattering theory of Tiersten we obtain the necessary hole-acoustic phonon transition rates, with no adjustable parameters, as a first principles input to the transport equations. ... |
|
| Long Term Evaluation of the Effects of Shale Oil Produced JP-4 on Aircraft Construction Materials |
APR 1983 |
|
| Authors:
B. H. Wilt; J. N. Dues; DAYTON UNIV OH RESEARCH INST
|
| Various fuel system materials including elastomers, structural adhesives, and tank coatings were subjected to accelerated agings in both petroleum produced and shale oil produced JP-4 fuels. Comparisons were made of the test results in the different fuels. There was no significant difference in the test results for most materials. There was, however, significantly more deterioration of buna N and polyurethane elastomers in shale oil JP-4 than in petroleum derived JP-4. ... |
|
| Aircraft Transparency Testing Methodology and Evaluation Criteria. Part 1. Test Methods and Information Analysis |
APR 1983 |
|
| Authors:
Kenneth I. Clayton; Blaine S. West; DAYTON UNIV OH RESEARCH INST
|
| This two-part report defines a methodology and criteria for testing and evaluating the durability of high performance aircraft transparencies through the use of simulated in-service environments. Part 1 presents and analyzes relevant information data on applicable operational environments, candidate test methods, and previously used simulation/testing techniques. Appropriate corrective action is recommended to circumvent knowledge voids and/ or test method deficiencies. A realistic and cost-effective durability evaluation criteria is presented in ... |
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| Aircraft Transparency Testing Methodology and Evaluation Criteria. Part 2. Methodology Development for Improved Durability |
APR 1983 |
|
| Authors:
Kenneth I. Clayton; Blaine S. West; DAYTON UNIV OH RESEARCH INST
|
| This two-part report defines a methodology and criteria for testing and evaluating the durability of high performance aircraft transparencies through the use of simulated in-service environments. Part 1 presents and analyzes relevant information data on applicable operational environments, candidate test methods, and previously used simulation/testing techniques. Appropriate corrective action is recommended to circumvent knowledge voids and/ or test method deficiencies. A realistic and cost-effective durability evaluation criteria is presented in ... |
|
| Symposium on Applied Surface Analysis (4th). Parts 1 and 2 |
MAR 1983 |
|
| Authors:
John T. Grant; DAYTON UNIV OH RESEARCH INST
|
| The 4th Symposium on Applied Surface Analysis was held at the University of Dayton, 9-11 June 1982. This Symposium was held to meet a need, namely to show the transition between basic surface science research and applications of this research in areas of Air Force interest. Areas receiving special attention at this Symposium were ion implantation, corrosion, catalysis, thin films, and electronic materials. Other topics discussed included adsorption, oxidation, coatings, ... |
|
| Three-Dimensional Test Experience with a Transonic Adaptive-Wall Wind Tunnel |
MAR 1983 |
|
| Authors:
Donald J. Harney; DAYTON UNIV OH RESEARCH INST
|
| A square 9-inch wind tunnel with solid sidewalls and flexible upper and lower rod walls capable of 3-D contouring was used to test an axisymmetric and a winged lifting model at M=0.50 to 0.95. The simple, direct analytical method for wall contouring uses the model geometry for solid blockage and iterative model force data to adapt for lift and for wake blockage. Solid sidewall effects and the convergence of the ... |
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| Efficient ADI (Alternating Direction Implicit) and Spline ADI Methods for the Navier-Stokes Equations |
FEB 1983 |
|
| Authors:
Michele Napolitano; DAYTON UNIV OH RESEARCH INST
|
| This report provides an improved Alternating Direction Implicit (ADI) technique as well as a high-order-accurate spline ADI method, for the numerical solution of steady two-dimensional incompressible viscous flow problems. The vorticity-stream function Navier-Stokes equations are considered in a general curvilinear coordinate system, which maps an arbitrary two-dimensional flow domain in the physical plane into a rectangle in the computational plane. The stream function equation is parabolized in time by means ... |
|
| Strains from Projection Moire Data |
FEB 1983 |
|
| Authors:
B. Basava Raju; Blaine S. West; Andrew J. Piekutowski; DAYTON UNIV OH RESEARCH INST
|
| The main objective of this program was to determine and evaluate the surface strains from out-of-plane deformations determined by the projection moire melthod of large surfaces experiencing static loads. The program consisted of three primary tasks: (1) design of an experiment consisting of a four-point bending fixture and a 26x6x1/4 inch flat test specimen, moire device, strain gage instrumentation, and dial gages, and the collection of experimental data for various ... |
|
| A Model for the Surface Wind Field in Complex Terrain |
JAN 1983 |
|
| Authors:
Patrick A. Haines; John L. Keller; Charles D. MacArthur; Jerry G. Jensen; DAYTON UNIV OH RESEARCH INST
|
| A model for calculating terrain-influenced surface (6 meter) wind fields is described. The model determines locally generated slope and valley winds as well as mechanically affected changes in the general wind due to sheltering, diverting, ridge enhancement, and separated flow. A procedure is also given for the generation of an optimal computation grid on which the wind field is computed. Winds calculated on this optimal, and usually uneven grid, may ... |
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| Improved Materials for Composite and Adhesive Joints |
JAN 1983 |
|
| Authors:
R. Kim; W. Click; J. Hartness; M. Koenig; M. Rich; DAYTON UNIV OH RESEARCH INST
|
| This report presents a summary of the work performed by the University of Dayton Research Institute during the period 1 Sept 1982 through 31 Aug 1982. Research was conducted in the following areas: Processing and Evaluation of Composites, Adhesive Bonded Joints, Interface/Interphase Characterization, and Mechanics of Composites and Adhesive Bonded Joints. |
|
| Characterization of High Temperature Polymeric Damping Materials |
JAN 1983 |
249 pages |
| Authors:
Richard P. Chartoff; Ival O. Salyer; Michael L. Drake; John M. Butler; Daniel E. Miller; Jerald L. Burkett; Charles W. Griffen; William A. Price; DAYTON UNIV OH RESEARCH INST
|
| An exploratory development program was carried out to find polymer systems that are effective energy absorbers for vibration damping purposes in the temperature range from 300 degrees F (149 deg. C) to 700 degrees F (371 deg. C). The study concentrated on aromatic backbone structures of the type that were known to have good thermal stabilities and glass transitions falling in the temperature range of interest. Among the types of ... |
|
| Alternate T-38 Transparency Development. Part III. Instructor's Windshield. |
JAN 1983 |
|
| Authors:
Gregory J. Stenger; DAYTON UNIV OH RESEARCH INST
|
| The development of a bird impact resistant T-38 instructor's windshield resulted from recent low level mission usage which significantly increases the danger of sustaining a bird impact and has caused concern within the Air Training Command (ATC) over pilot safety and aircraft survivability. The program has established the existing capability of in-service T-38 instructor's windshields and the maximum capability of the modified instructor's windshield frame and support structure which is ... |
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| AIRCRAFT TRANSPARENCY TESTING METHODOLOGY AND EVALUATION CRITERIA. PART 2. METHODOLOGY DEVELOPMENT FOR IMPROVED DURABILITY. |
1983 |
|
| Authors:
K. I. Clayton; B. S. West; DAYTON UNIV OH RESEARCH INST
|
|
| HIGH STRAIN RATE CHARACTERIZATION OF MATERIALS. |
1983 |
|
| Authors:
S. J. Bless; A. M. Rajendran; D. Dawicke; D. L. Paisley; DAYTON UNIV OH RESEARCH INST
|
|
| Rain Erosion Mechanisms on Polyurethane and Fluorelastomer Coated Composite Constructions. |
1983 |
|
| Authors:
Charles J. Hurley; Joseph Zahavi; George F. Schmitt; DAYTON UNIV OH RESEARCH INST
|
| An investigation was undertaken to determine the rain erosion impact resistance of polyurethane and fluoroelastomer coatings on selected composite constructions at 90 degrees and 30 degrees impact angles. The effects of impingment angle, composite construction, and rainfield exposure duration were examined. Cratering initiation and crack propagation processes were observed by scanning electron microscopy techniques. The degree of coating surface damage was greater for the fluoroelastomer coated composites as a function ... |
|
| Scattering in ZnSe Laser Windows. |
1983 |
|
| Authors:
John A. Detrio; DAYTON UNIV OH RESEARCH INST
|
|
| MAGNA (Materially and Geometrically Nonlinear Analysis). Part II. Preprocessor Manual |
DEC 1982 |
|
| Authors:
T. S. Bruner; Robert A. Brockman; K. A. Primrose; DAYTON UNIV OH RESEARCH INST
|
| A preprocessor system developed for use in connection with three- dimensional finite element analysis is described. The system consists of several data entry modules, a central preprocessor and various data translation and conversion utilities. Data entry and generation functions include keyboard, digitizer, and file inputs, which are oriented toward the type of thick shell geometry currently encountered in aircraft transparency analysis. The main preprocessor operates on models in superelement form, ... |
|
| MAGNA (Materially and Geometrically Nonlinear Analysis). Part IV. Quick- Reference Manual |
DEC 1982 |
|
| Authors:
Robert A. Brockman; DAYTON UNIV OH RESEARCH INST
|
| This manual summarizes access and operating procedures for the MAGNA finite element analysis program and related pre- and postprocessing programs. Parallel descriptions are given for CDC, VAX, and CRAY versions of the programs where applicable. The overall organization of the system is also described, including possible data paths and data file types. The manual is intended to provide a broad summary of the MAGNA system, as well as a concise ... |
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| MAGNA (Materially and Geometrically Nonlinear Analysis). Part III. Postprocessor Manual |
DEC 1982 |
|
| Authors:
Robert A. Brockman; T. S. Bruner; M. J. Hecht; M. P. Bouchard; M. E. Wright; DAYTON UNIV OH RESEARCH INST
|
| Three computer graphics programs, designed to present the results of finite element structural analysis in a readily assimilated form, are described. The first, GPLOT, performs plotting of original and/or deformed mesh geometries. A second program, CPLOT, produces contour or relief maps of displacement, strain, or stress results. These two programs are command-driven and offer a wide variety of display options. The third program, XYPLOT, generates variable- versus-variable plots with user-defined ... |
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| MAGNA (Materially and Geometrically Nonlinear Analysis). Part I. Finite Element Analysis Manual |
DEC 1982 |
|
| Authors:
R. A. Brockman; DAYTON UNIV OH RESEARCH INST
|
| The finite element program MAGNA (Materially and Geometrically Nonlinear Analysis), developed for the nonlinear static and dynamic analysis of complex three-dimensional structures, is described. This program is applicable to large structural response problems involving bars, membranes, beams, plates, shells, and three-dimensional solids, experiencing large displacements, finite strains, large rotations, and plastic deformation. The theoretical basis of MAGNA and the numerical procedures employed are described in detail. Several sample analyses are ... |
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| The Application of a Nonlinear Fracture Mechanics Parameter to Ductile Fatigue Crack Growth |
DEC 1982 |
126 pages |
| Authors:
G. A. Hartman III; A. M. Rajendran; D. S. Dawicke; DAYTON UNIV OH RESEARCH INST
|
| This report describes the methodology for predicting fatigue crack growth rate response of cracked structural components wherein the assumptions of linear elastic fracture mechanics are violated. Fatigue crack growth rate tests were conducted on copper specimens using compact tension (CT), centercracked panel (CCP), and radial-hole cracked (RHC) geometries. The CT and CCP specimens provided baseline fatigue crack growth rate data that were utilized to predict both the fatigue crack growth ... |
|
| Damping Materials, Finite Elements and Special Projects |
DEC 1982 |
|
| Authors:
M. Ruddell; P. A. Graf; M. F. Kluesener; D. M. Hopkins; W. Goddard; DAYTON UNIV OH RESEARCH INST
|
| This report denotes work under the subject contract in the area of polymeric and enamel material damping properties measurement, finite element analysis of damped components and some special projects, including state-of-the- art mobility measurement evaluations and development of a unique high temperature, high driving force electro-magnetic transducer. (Author) |
|
| Influence of Processing in the Solid State Morphology of ABPBI/PBT polymeric Composite Films: X-Ray Studies |
NOV 1982 |
55 pages |
| Authors:
A. K. Kulshreshtha; G. E. Price; DAYTON UNIV OH RESEARCH INST
|
| X-ray diffraction patterns of ABPBI/PBT polyblend films suggest the formation of polymer-solvent complexes at the molecular level. This effect may be misinterpreted as a new phase formed as a result of blending the two polymers. Polymer-solvent complexes are crystalline and can be oriented by usual methods. The nature of the x-ray diagram of the polymer-solvent complex depends upon blend composition, type of solvent and the method employed for film processing ... |
|
| Vitreous Enamel Damping Material Development |
NOV 1982 |
|
| Authors:
Binod Kumar; DAYTON UNIV OH RESEARCH INST
|
| This report describes the results of several experimental investigations pertaining to the effects of composition, viscosity, microstructure, and constraining layer on the damping properties of vitreous enamels. New vitreous enamels such as mixed alkali silicate, lead silicate, and two phase fluoride composition have been characterized. The mixed alkali and lead silicate compositions exhibits the characteristic, viscoelastic damping peak. The damping temperatures and the peak intensities are compositions dependent. The fluoride ... |
|
| Numerical Simulation of Flow around a Three-Dimensional Turret |
NOV 1982 |
|
| Authors:
S. C. Purohit; DAYTON UNIV OH RESEARCH INST
|
| The compressible Navier-Stokes equations in mass averaged variables are numerically solved for flow around a surface mounted turret. The three- dimensional unsteady separated flow is investigated with emphasis on the near wake region. The computation is performed on the CRAY-1 computer using MacCormack's explicit finite difference scheme. For the free stream Mach number 0.55 and Reynolds number 10.3 x 1,000,000/m, the time dependent calculation is carried out for 55,800 grid ... |
|
| Mechanical Property Data on P/M Aluminum X7091-T7E69 Extrusion |
OCT 1982 |
|
| Authors:
John J. Ruschau; Scott K. Jarvis; DAYTON UNIV OH RESEARCH INST
|
| A mechanical property investigation was performed on aluminum X7091- T7E69 extrusion, a recently developed alloy produced using powder-metallurgy technology. Properties examined were tensile and compression, smooth and notched fatigue, fracture, fatigue crack growth, and stress corrosion cracking. For notched fatigue investigations, stress concentration factors as high as 10 were examined. (Author) |
|
| QRC Evaluation of Materials and Processes |
OCT 1982 |
|
| Authors:
D. R. Askins; R. R. Cervay; K. A. Davis; D. L. Hart; K. L. Lindsay; DAYTON UNIV OH RESEARCH INST
|
| Materials evaluations under the categories of Alloys and Composites; Electronic Failure Analysis; Fibrous materials; Elastomers; Plastics, Adhesives and Composites; and Lubricants were completed during the contract period. The section entitled Engineering Data on Alloys and Composites includes materials properties evaluations of metal alloys and composite structural components. The next section, Electronic Fauilure Analysis, presents the results of failure analyses of a number of aircraft electronic components. Section 3, Fibrous Materials, ... |
|
| High Frequency Fatigue of Turbine Blade Material |
OCT 1982 |
|
| Authors:
Richard C. Goodman; Alexander M. Brown; DAYTON UNIV OH RESEARCH INST
|
| This increased fatigue crack growth rate at elevated temperature due to high frequency loading is examined. The crack growth rate is found to depend upon major cycle stress intensity factor, hold-time and minor cycle frequency, and amplitude for a given temperature. The elevated tests also demonstrate a transition from creep crack growth dominant to fatigue crack growth dominant at values of minor cycle amplitude above a threshold value. A model ... |
|
| Automated Design of Damage Resistant Structures. Volume I. Theory and Application |
OCT 1982 |
147 pages |
| Authors:
Ronald F. Taylor; DAYTON UNIV OH RESEARCH INST
|
| This report documents an effort to develop an optimality criterion approach to the design of damage tolerant structures subject to stress, deflection, and frequency requirements. Damage conditions are treated in an integral manner in the resizing algorithm. An iterative reanalysis procedure is used to improve the efficiency of the static analyses that are needed as the optimization proceeds. In this volume of the report, the theoretical development is given together ... |
|
| Automated Design of Damage Resistant Structures. Volume II. Program User's Manual |
OCT 1982 |
200 pages |
| Authors:
Ronald F. Taylor; DAYTON UNIV OH RESEARCH INST
|
| This report documents an effort to develop an optimality criterion approach to the design of damage tolerant structures subject to stress, deflection, and frequency requirements. Damage conditions are treated in an integral manner in the resizing algorithm. An iterative reanalysis procedure is used to improve the efficiency of the static analyses that are needed as the optimization proceeds. In this volume of the report, input instructions to the computer code ... |
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Reports by Corporate Author
