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May 31, 2011
05/11

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Mittaz, J. P. D.; Stewart, G., et al; Kaastra, J. S.; Tamura, T.; Fabian, A. C.; Mushotzky, F.; Peterson, J. R.; Ikebe, Y.; Lumb, D. H.; Paerels, F.

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We present the results of an analysis of broad band UV observations of the central regions of Abell 1795 observed with the optical monitor on XMM-Newton. As have been found with other UV observations of the central regions of clusters of galaxies, we find evidence for star formation. However, we also find evidence for absorption in the cD galaxy on a more extended scale than has been seen with optical imaging. We also report the first UV observation of part of the filamentary structure seen in...

Topics: GRID GENERATION (MATHEMATICS), COMPUTATIONAL GRIDS, GEOMETRY, AEROSPACE SYSTEMS, TURBOMACHINERY

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418

Jul 25, 2010
07/10

by
NON

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A common recommendation is established for the implementation of a spacecraft telecommand data routing service by the agencies participating in the CCSDS. The operating principles and procedures for the CCSDS are defined in a reference. The context of the data routing service within the overall telecommand system is described in another reference. This recommendation addresses the procedures and data unit formats implemented within the segmentation layer and the transfer layer of the...

Topics: ALGORITHMS, COMPUTER NETWORKS, REFINING, BANDWIDTH, GRID GENERATION (MATHEMATICS), MATRICES...

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160

May 28, 2011
05/11

by
Thornton, E. A

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A technique for full-field measurement of surface temperature and in-plane strain using a single grid imaging technique was demonstrated on a sample subjected to thermally-induced strain. The technique is based on digital imaging of a sample marked by an alternating line array of La2O2S:Eu(3) thermographic phosphor and chromium illuminated by a UV lamp. Digital images of this array in unstrained and strained states were processed using a modified spin filter. Normal strain distribution was...

Topics: RESEARCH, HYPERSONIC FLOW, GRID GENERATION (MATHEMATICS), UNSTRUCTURED GRIDS (MATHEMATICS),...

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422

Jun 3, 2011
06/11

by
Stanford, Malcolm K.; Yanke, Anne M.; DellaCorte, Christophe

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PS304 is a high temperature composite solid lubricant coating composed of Ni-Cr, Cr2O3, BaF2-CaF2 and Ag. The effect of reducing chromium content on the formation of voids in the Ni-Cr particles after heat treatment in PS304 coating was investigated. Coatings were prepared with Ni-20Cr or Ni-10Cr powder and in various combinations with the other constituents of PS304 (i.e., chromia, silver and eutectic BaF2-CaF2 powders) and deposited on metal substrates by plasma spray. Specimens were exposed...

Topics: BLACK HOLES (ASTRONOMY), MATHEMATICAL MODELS, GRID GENERATION (MATHEMATICS), CONVERGENCE, EVOLUTION...

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297

Jun 12, 2011
06/11

by
Abdul-Azia, Ali; Baaklini, George Y.; Trudell, Jeffrey J

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This study describes the finite-element analyses and the NDE modality undertaken on two flywheel rotors that were spun to burst speed. Computed tomography and dimensional measurements were used to nondestructively evaluate the rotors before and/or after they were spun to the first crack detection. Computed tomography data findings of two- and three-dimensional crack formation were used to conduct finite-element (FEA) and fracture mechanics analyses. A procedure to extend these analyses to...

Topics: COMPUTATIONAL GRIDS, CRATERING, TARGETS, HYDRODYNAMICS, COMPUTER PROGRAMS, PROVING, GRID GENERATION...

417
417

May 29, 2011
05/11

by
Haddock, M. Reed; McLennan, Michael L

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An improved tensile adhesion button has been designed and tested that results in higher measured tensile adhesion strength while providing increased capability for testing high strength epoxy adhesive systems. The best attributes of two well-established tensile button designs were combined and refined into an optimized tensile button. The most significant design change to the tensile button was to improve alignment of the bonded tensile button specimens during tensile testing by changing the...

Topics: VARIABILITY, GRID GENERATION (MATHEMATICS), SIMULATION, CLIMATE MODELS, SUMMER, STRETCHING, HEIGHT,...

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199

Jun 9, 2011
06/11

by
Butler, Ricky W.; Caldwell, James L.; DiVito, Ben L

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This paper presents a high-level design for a reliable computing platform for real-time control applications. The design tradeoffs and analyses related to the development of a formally verified reliable computing platform are discussed. The design strategy advocated in this paper requires the use of techniques that can be completely characterized mathematically as opposed to more powerful or more flexible algorithms whose performance properties can only be analyzed by simulation and testing....

Topics: NEWTON-RAPHSON METHOD, UNSTRUCTURED GRIDS (MATHEMATICS), GRID GENERATION (MATHEMATICS), STRUCTURED...

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376

Jun 12, 2011
06/11

by
Paris, Deidre; Trevino, Luis C.; Watson, Michael D

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Integrated Vehicle Health Management (IVHM) systems for aerospace vehicles, is the process of assessing, preserving, and restoring system functionality across flight and techniques with sensor and communication technologies for spacecraft that can generate responses through detection, diagnosis, reasoning, and adapt to system faults in support of Integrated Intelligent Vehicle Management (IIVM). These real-time responses allow the IIVM to modify the affected vehicle subsystem(s) prior to a...

Topics: GRID GENERATION (MATHEMATICS), UNSTRUCTURED GRIDS (MATHEMATICS), CARTESIAN COORDINATES, FLOW...

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299

Jun 3, 2011
06/11

by
Percy, Thomas K.; Taylor, Travis; Powell, T. Conle

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A study was performed in conjunction with the In Space Technology Investment Area of NASA's Marshall Space Flight Center to investigate potential applications of solar sails to Mars missions. While solar sails have been proposed as possible candidates for several missions, including Geostorm and a Polar Observer mission, Mars has often been overlooked as a potential destination. It was found that solar sails may have potential in Mars observation missions with smaller payloads. Sail aerocapture...

Topics: GRID GENERATION (MATHEMATICS), EXPERT SYSTEMS, COMPUTATIONAL FLUID DYNAMICS, PROCEDURES, DATA...

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502

May 22, 2011
05/11

by
Collins, Martin J.; Kraemer, Sylvia K

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Presented are the acknowledgements and introduction sections of the book 'Space: Discovery and Exploration.' The goal of the book is to address some basic questions of American space history, including how this history compares with previous eras of exploration, why the space program was initiated when it was, and how the U.S. space program developed. In pursuing these questions, the intention is not to provide exhaustive answers, but to point the reader toward a more varied picture of how our...

Topics: ALGORITHMS, COMPUTATIONAL FLUID DYNAMICS, COMPUTATIONAL GRIDS, GRID GENERATION (MATHEMATICS),...

898
898

May 29, 2011
05/11

by
Leroy, Mar

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The BOREAS HYD-9 team collected data on precipitation and strearnflow over portions of the NSA and SSA. This data set contains Cartesian maps of rain accumulation for I -hour and daily periods during the summer of 1994 over the SSA only (not the full view of the radar). A parallel set of 1-hour maps for the whole radar view has been prepared and is available upon request from the HYD-09 personnel. An incidental benefit of the areal selection was the elimination of some of the less accurate...

Topics: COMPUTER GRAPHICS, CONTOURS, GRID GENERATION (MATHEMATICS), IMAGE PROCESSING, TURBINE PUMPS, MACH...

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225

Jun 13, 2011
06/11

by
Player, Charles J.; Cheatwood, F. McNeil; Corliss, Jame

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Achieving the objectives of NASA s Vision for Space Exploration will require the development of new technologies, which will in turn require higher fidelity modeling and analysis techniques, and innovative testing capabilities. Development of entry systems technologies can be especially difficult due to the lack of facilities and resources available to test these new technologies in mission relevant environments. This paper discusses the technology development process to bring inflatable...

Topics: COMPUTATIONAL FLUID DYNAMICS, COMPUTATIONAL GRIDS, TOPOLOGY, GRID GENERATION (MATHEMATICS),...

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368

May 31, 2011
05/11

by
Wright, Michael J.; Loomis, Mark; Papadopoulos, Perikli

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Computational fluid dynamics (CFD) is used to simulate the wake flow and afterbody heating of the Project Fire II ballistic reentry to Earth at 11.4 km/sec. Laminar results are obtained over a portion of the trajectory between the initial heat pulse and peak afterbody heating. Although non-catalytic forebody convective heating results are in excellent agreement with previous computations, initial predictions of afterbody heating were about a factor of two below the experimental values. Further...

Topics: COMPUTATIONAL FLUID DYNAMICS, GRID GENERATION (MATHEMATICS), CARTESIAN COORDINATES, COMPUTERIZED...

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158

May 23, 2011
05/11

by
Chu, Barbara C. F.; Orgel, Leslie E

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Conjugates of biotin with the decamer of glutamic acid (glu(sub 10)) and the trimer of D,L-2-amino-5-phosphonovaleric acid (I) have been synthesized, and it has been shown that they mediate the binding of avidin to hydroxylapatite. In a similar way a conjugate of methotrexate with glu(sub 10) mediates the binding of dihydrofolate reductase to the mineral. The presentation of ligands on the hydroxylapatite component of bone may find applications in clinical medicine.

Topics: GRID GENERATION (MATHEMATICS), PREDICTOR-CORRECTOR METHODS, WINGS, COMPUTATIONAL GRIDS, LAPLACE...

313
313

Jun 9, 2011
06/11

by
Lim, Kyong B

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A framework for designing control systems directly from substructure models and uncertainties is proposed. The technique is based on combining a set of substructure robust control problems by an interface stiffness matrix which appears as a constant gain feedback. Variations of uncertainties in the interface stiffness are treated as a parametric uncertainty. It is shown that multivariable robust control can be applied to generate centralized or decentralized controllers that guarantee...

Topics: COMPUTATIONAL FLUID DYNAMICS, FLOW DISTRIBUTION, GRID GENERATION (MATHEMATICS), FLOW DEFLECTION,...

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275

May 31, 2011
05/11

by
Zhu, Dongming; Fox, Dennis S.; Miller, Robert A

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The development of the pulse detonation engine (PDE) requires robust design of the engine components that are capable of enduring harsh detonation environments. In this study, a high cycle thermal fatigue test rig was developed for evaluating candidate PDE combustor materials using a CO2 laser. The high cycle thermal fatigue behavior of Haynes 188 alloy was investigated under an enhanced pulsed laser test condition of 30 Hz cycle frequency (33 ms pulse period, and 10 ms pulse width including...

Topics: HAMILTON-JACOBI EQUATION, DISCRETE FUNCTIONS, WEIGHTING FUNCTIONS, POLYNOMIALS, APPROXIMATION, GRID...

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248

Jul 25, 2010
07/10

by
Byrd, Gregory P

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Ground-based and airborne Doppler radar and LIDAR systems are being designed to alert pilots when a hazardous windshear is present. A key element in this design effort is understanding the microburst itself. This is accomplished by means of the TASS model which was developed for NASA by Proctor (1987a,b). The time-dependent TASS model has two vesions: a two-demensional high resolution axisymmetric model, and a three-demensional model. The model includes a sophisticated parameterization of cloud...

Topics: CYLINDRICAL BODIES, FINITE ELEMENT METHOD, GRID GENERATION (MATHEMATICS), HEAT TRANSFER, MESH,...

A new method of domain decomposition has been developed for generating unstructured grids in subdomains either sequentially or using multiple computers in parallel. Domain decomposition is a crucial and challenging step for parallel grid generation. Prior methods are generally based on auxiliary, complex, and computationally intensive operations for defining partition interfaces and usually produce grids of lower quality than those generated in single domains. The new technique, referred to as...

Topics: NASA Technical Reports Server (NTRS), UNSTRUCTURED GRIDS (MATHEMATICS), DOMAINS, DECOMPOSITION,...

This document serves as the final report for the grant titled Surface Generation and Cartesian Mesh Support . This completed work was in algorithmic research into automatically generating surface triangulations from CAD geometries. NASA's OVERFLOW and Cart3D simulation packages use surface triangulations as an underlying geometry description and the ability to automatically generate these from CAD files (without translation) substantially reduces both the wall-clock time and expertise required...

Topics: NASA Technical Reports Server (NTRS), COMPUTER AIDED DESIGN, GRID GENERATION (MATHEMATICS),...

This report summarizes the research undertaken, at Aeronautics Department of the Massachusetts Institute of Technology, during the approximately five year period, February 94 - March 99. This work is part of a larger effort aimed at providing a reliable fast turn around capability for the prediction of hypersonic flows over complete vehicle configurations.

Topics: NASA Technical Reports Server (NTRS), RESEARCH, HYPERSONIC FLOW, GRID GENERATION (MATHEMATICS),...

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148

May 22, 2011
05/11

by
Stadermann, Frank J.; Amari, Sachiko; Foote, John; Swan, Pat; Walker, Robert M.; Zinner, Erns

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Previous secondary ion mass spectrometry (SIMS) studies of extended impact features from LDEF capture cell experiment AO187-2 showed that it is possible to distinguish natural and man-made particle impacts based on the chemical composition of projectile residues. The same measurement technique has now been applied to specially prepared gold target impacts from experiment AO187-1 in order to identify the origins of projectiles that left deposits too thin to be analyzed by conventional...

Topics: COMPUTATIONAL GRIDS, EULER-LAGRANGE EQUATION, FLOW DISTRIBUTION, GRID GENERATION (MATHEMATICS),...

A fast algorithm was developed for accurately generating boundary conforming, three dimensional, consecutively refined, computational grids applicable to arbitrary axial turbomachinery geometry. The method is based on using a single analytic function to generate two dimensional grids on a number of coaxial axisymmetric surfaces positioned between the hub and the shroud. These grids are of the "O" type and are characterized by quasi-orthogonality, geometric periodicity, and an adequate...

Topics: NASA Technical Reports Server (NTRS), ALGORITHMS, BOUNDARIES, GEOMETRY, GRID GENERATION...

352
352

May 23, 2011
05/11

by
Fricke, Robert W., Jr

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STS-79 was the fourth of nine planned missions to the Russian Mir Space Station. This report summarizes the activities such as rendezvous and docking and spaceborne experiment operations. The report also discusses the Orbiter, External Tank (ET), Solid Rocket Boosters (SRB), Reusable Solid Rocket Motor (RSRM) and the space shuttle main engine (SSME) systems performance during the flight. The primary objectives of this flight were to rendezvous and dock with the Mir Space Station and exchange a...

Topics: ALGORITHMS, STRUCTURED GRIDS (MATHEMATICS), GRID GENERATION (MATHEMATICS), ERROR ANALYSIS, THREE...

226
226

May 31, 2011
05/11

by
Camarotte, C.; Lancaster, G. S.; Eichenberg, D.; Butler, S. M.; Miller, J. R

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Recent improvements in energy densities of batteries open the possibility of using electric rather that hydraulic actuators in space vehicle systems. However, the systems usually require short-duration, high-power pulses. This power profile requires the battery system to be sized to meet the power requirements rather than stored energy requirements, often resulting in a large and inefficient energy storage system. Similar transient power applications have used a combination of two or more...

Topics: CARTESIAN COORDINATES, GRID GENERATION (MATHEMATICS), THREE DIMENSIONAL FLOW, BOUNDARY CONDITIONS,...

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966

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Discussed here are the activities of the Research Triangle Institute (RTI) Technology Applications Team for the period 1 October 1990 through 30 September 1991. Topics researched include automated data acquisition and analysis of highway pavement cracking, thermal insulation for refrigerators, the containment of paint removed from steel structures, improved technologies for Kuwait oil well control, sprayed zinc coatings for corrosion control of reinforcing steel in bridges, and the monitoring...

Topics: COMPUTATIONAL GRIDS, TETRAHEDRONS, GRID GENERATION (MATHEMATICS), OPTIMIZATION, THREE DIMENSIONAL...

This report contains an overview of the VGRIDSG unstructured surface grid generation program. The VGRIDSG program was created from the VGRID3D unstructured grid generation program developed by Vigyan, Inc. The purpose of this report is to document the changes from the original VGRID3D program and to describe the capabilities of the new program.

Topics: NASA Technical Reports Server (NTRS), COMPUTATIONAL GRIDS, COMPUTER PROGRAMS, GRID GENERATION...

561
561

Jun 9, 2011
06/11

by
Wang, James M.; Jones, Christopher T.; Nixon, Mark W

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The Short-Haul-Civil-tiltrotor (SHCT) component of the NASA Aviation System Capacity Program is an effort to develop the technologies needed for a potential 40-passenger civil tiltrotor. The variable diameter tiltrotor (VDTR) is a Sikorsky concept aimed at improving tiltrotor hover and cruise performance currently limited by disk loading that is much higher in hover than conventional helicopter, and much lower in cruise than turbo-prop systems. This paper describes the technical merits of using...

Topics: COMPUTATIONAL FLUID DYNAMICS, FLOW VISUALIZATION, COMPUTER PROGRAMS, CHUTES, GRID GENERATION...

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315

Jul 26, 2010
07/10

by
Mirzadeh, F.; Pindera, Marek-Jerzy; Herakovich, Carl T

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Elements of the analytical/experimental program to characterize the response of silicon carbide titanium (SCS-6/Ti-15-3) composite tubes under biaxial loading are outlined. The analytical program comprises prediction of initial yielding and subsequent inelastic response of unidirectional and angle-ply silicon carbide titanium tubes using a combined micromechanics approach and laminate analysis. The micromechanics approach is based on the method of cells model and has the capability of...

Topics: COMPUTATIONAL FLUID DYNAMICS, TURBOMACHINERY, COMPUTATIONAL GRIDS, COMPUTER PROGRAMS, GRID...

Two elliptic grid generation schemes that yield orthogonal grids are presented (FGBR and UBGR). With the UBGR scheme, the grid points on the flow boundaries are automatically determined by the algorithm, while the FBGR scheme at most one half of the boundary grid points may be prespecified and the remainder of boundary grid points are determined automatically. Numerical examples show their capability of easy stretching, clustering and shock fitting while maintaining orthogonality of grid. The...

Topics: NASA Technical Reports Server (NTRS), CLUSTER ANALYSIS, COORDINATES, FLOW CHARACTERISTICS, GRID...

A fast and versatile procedure for algebraically generating boundary conforming computational grids for use with finite-volume Euler flow solvers is presented. A semi-analytic homotopic procedure is used to generate the grids. Grids generated in two-dimensional planes are stacked to produce quasi-three-dimensional grid systems. The body surface and outer boundary are described in terms of surface parameters. An interpolation scheme is used to blend between the body surface and the outer...

Topics: NASA Technical Reports Server (NTRS), COMPUTATIONAL GRIDS, FINITE VOLUME METHOD, GRID GENERATION...

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249

Jun 1, 2011
06/11

by
Busemann, Adol

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The calculation of infinitesimal conical supersonic flow has been applied first to the simplest examples that have also been calculated in another way. Except for the discovery of a miscalculation in an older report, there was found the expected conformity. The new method of calculation is limited more definitely to the conical case.

Topics: WAVELET ANALYSIS, PRESSURE, GRID GENERATION (MATHEMATICS), ALGORITHMS, DISSIPATION, TURBULENCE,...

Bezier and B-spline patches are popular tools in surface modeling. With these methods, a surface is represented by the tensor product of univariate approximations. The extension of this concept to three-dimensions is obvious and can be applied to the problem of grid generation. This report will demonstrate how three-dimensional patches can be used in solid modeling and in the generation of grids. Examples will be given demonstrating the ability to generate three-dimensional grids directly from...

Topics: NASA Technical Reports Server (NTRS), COMPUTATIONAL GEOMETRY, COMPUTATIONAL GRIDS, GRID GENERATION...

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414

Aug 1, 2010
08/10

by
Moseley, Warre

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Applying ITS technology to the shuttle diagnostics would not require the rigor of the Petri Net representation, however it is important in providing the animated simulated portion of the interface and the demands placed on the system to support the training aspects to have a homogeneous and consistent underlying knowledge representation. By keeping the diagnostic rule base, the hardware description, the software description, user profiles, desired behavioral knowledge, and the user interface in...

Topics: COMPUTATIONAL FLUID DYNAMICS, COMPUTATIONAL GRIDS, CONFERENCES, INTERACTIONAL AERODYNAMICS,...

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610

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Distinguished guests, ladies and gentlemen It gives me a great pleasure to welcome all of you to the ATRS World Conference being hosted jointly by Groupe ESC (Toulouse Business School) and the ENAC (Ecole Nationale de Aviation Civile). Today and tomorrow, in addition to the Opening and the Closing Plenary sessions, 112 papers will be presented on virtually all aspects of air transport and related topics. 2003 is a particularly challenging year to air transport policy makers, aviation executives...

Topics: AIRFOILS, LIFT, TRAILING EDGES, OPTIMIZATION, MATHEMATICAL MODELS, ALGORITHMS, SUBSONIC WIND...

A method is presented for computing orthogonal boundary fitted coordinate systems for geometries with coordinate distributions specified on all boundaries. The system which has found most extensive use in generating boundary fitted grids is made up of Poisson equations, of which the functions P and Q provide a means for controlling the spacing and density of grid lines in the coordinate system. While questions remain concerning the existence and uniqueness of orthogonal systems, the generating...

Topics: NASA Technical Reports Server (NTRS), BOUNDARIES, COORDINATES, GRID GENERATION (MATHEMATICS),...

Contents include the following: 1. An overview of the Loci Multidisciplinary Simulation System. 2. Topologically adaptive mesh generation. 3. Multidisciplinary simulations using Loci with the CHEM chemically reacting flow solver.

Topics: NASA Technical Reports Server (NTRS), SIMULATION, TOPOLOGY, LOCI, GRID GENERATION (MATHEMATICS),...

This report is the documentation of the work performed for the Subsonic Rotary Wing Project under the NASA s Fundamental Aeronautics Program. It was funded through Task Number NNC10E420T under GESS-2 Contract NNC06BA07B in the period of 10/1/2010 to 8/31/2011. The objective of the task is to provide support for the development of variable speed power turbine technology through application of computational fluid dynamics analyses. This includes work elements in mesh generation, multistage URANS...

Topics: NASA Technical Reports Server (NTRS), COMPUTATIONAL FLUID DYNAMICS, AERODYNAMICS, TURBINES, GRID...

A procedure for generating smooth uniformly clustered single-zone grids using enhanced elliptic grid generation has been demonstrated here for the Mars Science Laboratory (MSL) geometries such as aeroshell and canopy. The procedure obviates the need for generating multizone grids for such geometries, as reported in the literature. This has been possible because the enhanced elliptic grid generator automatically generates clustered grids without manual prescription of decay parameters needed...

Topics: NASA Technical Reports Server (NTRS), GRID GENERATION (MATHEMATICS), COMPUTATIONAL GRIDS,...

During this contract period, our work has focused on improvements to elliptic grid generation methods. There are two principle objectives in this project. One objective is to make the elliptic methods more reliable and efficient, and the other is to construct a modular code that can be incorporated into the National Grid Project (NGP), or any other grid generation code. Progress has been made in meeting both of these objectives. The two objectives are actually complementary. As the code...

Topics: NASA Technical Reports Server (NTRS), COMPUTATIONAL GRIDS, ELLIPTIC DIFFERENTIAL EQUATIONS, GRID...

An analytical transformation method which can map arbitrary physical coordinate grid distribution into desired computational coordinate with uniform grid distribution is derived. The transformation function and its higher derivatives are differentiable. Salient features include; (1) precise control of grid sizes; (2) more than one location of clustered grids; (3) exact positioning of particular computational nodes in the physical plane; and (4) ensuring several patches of uniformly spaced grids...

Topics: NASA Technical Reports Server (NTRS), COMPUTATION, GRID GENERATION (MATHEMATICS), TRANSFORMATIONS...

Several reports are attached to this document which contain the results of our research at the end of this contract period. Three of the reports deal with our work on generating surface grids. One is a preprint of a paper which will appear in the journal Applied Mathematics and Computation. Another is the abstract from a dissertation which has been prepared by Ahmed Khamayseh, a graduate student who has been supported by this grant for the last two years. The last report on surface grids is the...

Topics: NASA Technical Reports Server (NTRS), COMPUTATIONAL GRIDS, ELLIPTIC FUNCTIONS, GRID GENERATION...

A simple and efficient computational method is presented for unstructured surface grid generation. This method is built upon an advancing front technique combined with grid projection. The projection technique is based on a Newton-Raphson method. This combined approach has been successfully implemented for structured and unstructured grids. In this paper, the implementation for unstructured grid is discussed.

Topics: NASA Technical Reports Server (NTRS), NEWTON-RAPHSON METHOD, UNSTRUCTURED GRIDS (MATHEMATICS), GRID...

288
288

May 23, 2011
05/11

by
Johnson, Catherine L.; Sandwell, Davi

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The primary objective of the work executed under NAGW-4784 is to provide constraints on the thermal and tectonic evolution of Venus. Establishing thermal and tectonic evolution models requires not only geological, but geophysical constraints, in particular the nature of temporal and spatial variations in crustal and lithospheric thickness. The major topics of study completed under NAGW-4784 (described more fully below) are: (1) detailed analyses of the resolution of Magellan Line-Of-Site (LOS)...

Topics: COMPUTERIZED SIMULATION, MODULES, NONUNIFORMITY, SIMULATION, GRID GENERATION (MATHEMATICS),...

The objective of this research project is to develop efficient parallel automatic grid generation procedures for use in computational aerosciences. This effort is focused on a parallel version of the Finite Octree grid generator. Progress made during the first six months is reported.

Topics: NASA Technical Reports Server (NTRS), AEROSPACE SCIENCES, COMPUTATIONAL GEOMETRY, GRID GENERATION...

A new method of generating unstructured triangular/tetrahedral grids with high-aspect-ratio cells is proposed. The method is based on new grid-marching strategy referred to as 'advancing-layers' for construction of highly stretched cells in the boundary layer and the conventional advancing-front technique for generation of regular, equilateral cells in the inviscid-flow region. Unlike the existing semi-structured viscous grid generation techniques, the new procedure relies on a totally...

Topics: NASA Technical Reports Server (NTRS), COMPUTATIONAL FLUID DYNAMICS, COMPUTATIONAL GRIDS, GRID...

Our purpose in examining this test problem is to measure directly the effect of mesh refinement and the resulting mesh interfaces on a known wave that is sensitive to phase errors, while concurrently being able to visually display a meaningful picture of the effects of the refinement induced error on the solution. The refined mesh must be able to adequately capture the diffraction behavior, so that the plane wave front bends as it passes through the slit. Given that the coarse and refined...

Topics: NASA Technical Reports Server (NTRS), DIFFRACTION, GRID GENERATION (MATHEMATICS), PHASE ERROR,...

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729

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The SREL User's Handbook is designed to provide information needed by those who plan experiments involving the accelerators at this laboratory. Thus the Handbook will contain information on the properties of the machines, the beam parameters, the facilities and services provided for experimenters, etc. This information will be brought up to date as new equipment is added and modifications accomplished. This Handbook is influenced by the many excellent models prepared at other accelerator...

Topics: GRID GENERATION (MATHEMATICS), LOOP TRANSFER FUNCTIONS, MULTIBLOCK GRIDS, TOPOLOGY, COMPUTATIONAL...

In an earlier paper, Misner (2004, Class. Quant. Grav., 21, S243) presented a novel algorithm for computing the spherical harmonic components of data represented on a cubic grid. I extend Misner s original analysis by making detailed error estimates of the numerical errors accrued by the algorithm, by using symmetry arguments to suggest a more efficient implementation scheme, and by explaining how the algorithm can be applied efficiently on data with explicit reflection symmetries.

Topics: NASA Technical Reports Server (NTRS), SPHERICAL HARMONICS, ERROR ANALYSIS, MATHEMATICAL MODELS,...

A method for locally fairing uniform cubic B-spline curves and surfaces is presented. The algorithm uses an automated technique which detects undesirable geometric characteristics by using a local fairness criterion. The geometric entity is then smoothed using a method based on the repeated removal and insertion of the spline knots in the vicinity of the geometric irregularity.

Topics: NASA Technical Reports Server (NTRS), ALGORITHMS, CURVES, GEOMETRY, GRID GENERATION (MATHEMATICS),...

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251

May 23, 2011
05/11

by
Moriyama, Shin-Ichi; Hiraki, Naoji; Watanabe, Katsuhide; Kanemitsu, Yoich

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This paper describes a magnetically suspended linear pulse motor for a semiconductor wafer transfer robot in a vacuum chamber. The motor can drive a wafer transfer arm horizontally without mechanical contact. In the construction of the magnetic suspension system, four pairs of linear magnetic bearings for the lift control are used for the guidance control as well. This approach allows us to make the whole motor compact in size and light in weight. The tested motor consists of a double-sided...

Topics: COMPUTATIONAL GRIDS, GRID GENERATION (MATHEMATICS), FLOW DISTRIBUTION, FLUID BOUNDARIES,...