Imaginal wing discs of Drosophila melanogaster (fruit fly) defined during embryogenesis ultimately result in mature wings of stereotyped (specific) venation patterning. Major regulators of wing disc development are the epidermal growth factor receptor (EGF), Notch, Hedgehog (Hh), Wingless (Wg), and Dpp signaling pathways. Highly stereotyped vascular patterning is also characteristic of tissues in other organisms flown in space such as the mouse retina and leaves of Arabidopsis thaliana. Genetic...
Topics: NASA Technical Reports Server (NTRS), DROSOPHILA, ORGANISMS, MICROGRAVITY APPLICATIONS, GENES,...
Advances in Cadmium Zinc Telluride (Cd(sub 1-x)Zn(sub x)Te) growth techniques are needed for the production of large-scale arrays of gamma and x-ray astronomy. The research objective is to develop crystal growth recipes and techniques to obtain large, high quality CdZnTe single crystal with reduced defects, such as charge trapping, twinning, and tellurium precipitates, which degrade the performance of CdZnTe and, at the same time, to increase the yield of usable material from the CdZnTe ingot....
Topics: NASA Technical Reports Server (NTRS), CRYSTAL GROWTH, CADMIUM TELLURIDES, ZINC TELLURIDES,...
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Topics: NASA Technical Reports Server (NTRS), COMPUTER AIDED MANUFACTURING, SPACE MANUFACTURING, LOW...
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Topics: NASA Technical Reports Server (NTRS), ROBOTICS, ROBOTS, PRESENTATION, INTERNATIONAL SPACE STATION,...
No abstract available
Topics: NASA Technical Reports Server (NTRS), MATERIALS SCIENCE, INTERNATIONAL SPACE STATION, RACKS...
No abstract available
Topics: NASA Technical Reports Server (NTRS), MICROGRAVITY APPLICATIONS, INTERNATIONAL SPACE STATION,...
Bioreactor research is mostly limited to continuous stirred-tank reactors (CSTRs) which are not an option for microgravity (g) applications due to the lack of a gravity gradient to drive aeration as described by the Archimedes principle. Bioreactors and filtration systems for treating wastewater in g could avoid the need for harsh pretreatment chemicals and improve overall water recovery. Solution: Membrane Aerated Bioreactors (MABRs) for g applications, including possible use for wastewater...
Topics: NASA Technical Reports Server (NTRS), BIOREACTORS, MEMBRANE STRUCTURES, MULTIPLEXING, ATTACHMENT,...
As aerospace applications become ever more demanding, novel insulation materials with lower thermal conductivity, lighter weight and higher use temperature are required to fit the aerospace application needs. Having nanopores and high porosity, aerogels are superior thermal insulators, among other things. The use of silica aerogels in general is quite restricted due to their inherent fragility, hygroscopic nature, and poor mechanical properties, especially in extereme aerospace environments....
Topics: NASA Technical Reports Server (NTRS), CROSSLINKING, SILICON DIOXIDE, POLYIMIDES, ALUMINUM...
Flow boiling and condensation have been identified as two key mechanisms for heat transport that are vital for achieving weight and volume reduction as well as performance enhancement in future space systems. Since inertia driven flows are demanding on power usage, lower flows are desirable. However, in microgravity, lower flows are dominated by forces other than inertia (like the capillary force). It is of paramount interest to investigate limits of low flows beyond which the flow is inertial...
Topics: NASA Technical Reports Server (NTRS), CONDENSATION, BOILING, INTERNATIONAL SPACE STATION,...
A systematic analysis of the effect of convection on the microstructural evolution in cast binary, ternary and commercial Al-Si based alloys.
Topics: NASA Technical Reports Server (NTRS), DENDRITES, MICROSTRUCTURE, ALUMINUM ALLOYS, SILICON ALLOYS,...
NASA designed and operated the Intravenous Fluid Generation (IVGEN) experiment onboard the International Space Station (ISS), Increment 23/24, during May 2010. This hardware was a demonstration experiment to generate intravenous (IV) fluid from ISS Water Processing Assembly (WPA) potable water using a water purification technique and pharmaceutical mixing system. The IVGEN experiment utilizes a deionizing resin bed to remove contaminants from feedstock water to a purity level that meets the...
Topics: NASA Technical Reports Server (NTRS), INTRAVENOUS PROCEDURES, SPACEBORNE EXPERIMENTS, INTERNATIONAL...
The FASTRACK suborbital experiment platform has been developed to provide a capability for utilizing 2.5-5 minute microgravity flight opportunities anticipated from the commercial suborbital fleet (currently in development) for science investigations, technology development and hardware testing. It also provides "express rack" functionality to deliver payloads to ISS. FASTRACK fits within a 24" x 24" x 36" (61 cm x 61 cm x 91.4 cm) envelope and is capable of supporting...
Topics: NASA Technical Reports Server (NTRS), MICROGRAVITY APPLICATIONS, SUBORBITAL FLIGHT, SPACE...
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2004
2004
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Olsen, Mike E.; Liu, Yen; Vinokur, M.; Olsen, To
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An implementation of premixed equilibrium chemistry has been completed for the OVERFLOW code, a chimera capable, complex geometry flow code widely used to predict transonic flowfields. The implementation builds on the computational efficiency and geometric generality of the solver.
Topics: CALORIMETERS, FLAMMABILITY, MICROGRAVITY APPLICATIONS, SPACECRAFT ENVIRONMENTS, TEST STANDS,...
NASA has recognized the need for making additional heavy-ion collision measurements at the U.S. Brookhaven National Laboratory in order to support further improvement of several particle physics transport-code models for space exploration applications. FLUKA has been identified as one of these codes and we will review the nature and status of this investigation as it relates to high-energy heavy-ion physics.
Topics: NASA Technical Reports Server (NTRS), MONTE CARLO METHOD, HEAVY IONS, IONIC COLLISIONS, SPACE...
The Office of Biological and Physical Research (OBPR) is moving aggressively to align programs, projects, and products with the vision for space exploration. Research in advanced materials is a critical element in meeting exploration goals. Research in low gravity materials science in OBPR is being focused on top priority needs in support of exploration: 1) Space Radiation Shielding; 2) In Situ Resource Utilization; 3) In Situ Fabrication and Repair; 4) Materials Science for Spacecraft and...
Topics: NASA Technical Reports Server (NTRS), MICROGRAVITY APPLICATIONS, MATERIALS SCIENCE, RADIATION...
The objective of this project is to modify the standard oxygen consumption (cone) calorimeter (described in ASTM E 1354 and NASA STD 6001 Test 2) to provide a reproducible bench-scale test environment that simulates the buoyant or ventilation flow that would be generated by or around a burning surface in a spacecraft or extraterrestrial gravity level. This apparatus will allow us to conduct normal gravity experiments that accurately and quantitatively evaluate a material's flammability...
Topics: NASA Technical Reports Server (NTRS), CALORIMETERS, FLAMMABILITY, MICROGRAVITY APPLICATIONS,...
Materials processing in space has been studied both theoretically and experimentally for over 1/4 of a century. In the beginning, we naively spoke of zero gravity, elimination of convection, growth of perfect crystals, and eventual manufacturing in space. All of these appear to have fallen by the wayside. On the other hand, we have learned an unprecedented amount about the influences of gravity on materials processing. We have had many surprises, and not all experimental results have yet been...
Topics: NASA Technical Reports Server (NTRS), MICROGRAVITY, MICROGRAVITY APPLICATIONS, SPACE PROCESSING,...
The 2002 Microgravity Materials Science Conference was held June 25-26, 2002, at the Von Braun Center, Huntsville, Alabama. Organized by the Microgravity Materials Science Discipline Working Group, sponsored by the Physical Sciences Research Division, NASA Headquarters, and hosted by NASA Marshall Space Flight Center and member institutions under the Cooperative Research in Biology and Materials Science (CORBAMS) agreement, the conference provided a forum to review the current research and...
Topics: NASA Technical Reports Server (NTRS), CONFERENCES, GRAVITATIONAL EFFECTS, CRYSTAL GROWTH,...
This is Volume 3 of 3 of the 2000 Microgravity Materials Science Conference that was held June 6-8 at the Von Braun Center, Huntsville, Alabama. It was organized by the Microgravity Materials Science Discipline Working Group, sponsored by the Microgravity Research Division (MRD) at NASA Headquarters, and hosted by NASA Marshall Space Flight Center and the Alliance for Microgravity Materials Science and Applications (AMMSA). It was the fourth NASA conference of this type in the Microgravity...
Topics: NASA Technical Reports Server (NTRS), CONFERENCES, MICROGRAVITY APPLICATIONS, CRYSTAL GROWTH,...
This is Volume 2 of 3 of the 2000 Microgravity Materials Science Conference that was held June 6-8 at the Von Braun Center, Huntsville, Alabama. It was organized by the Microgravity Materials Science Discipline Working Group, sponsored by the Microgravity Research Division (MRD) at NASA Headquarters, and hosted by NASA Marshall Space Flight Center and the Alliance for Microgravity Materials Science and Applications (AMMSA). It was the fourth NASA conference of this type in the Microgravity...
Topics: NASA Technical Reports Server (NTRS), CONFERENCES, CRYSTAL GROWTH, MICROGRAVITY, MICROGRAVITY...
This is Volume 1 of 3 of the 2000 Microgravity Material Science Conference that was held June 6-8 at the Von Braun Center, Huntsville, Alabama. It was organized by the Microgravity Materials Science Discipline Working Group, sponsored by the Microgravity Research Division (MRD) at NASA Headquarters, and hosted by NASA Marshall Space Flight Center and the Alliance for Microgravity Materials Science and Applications (AMMSA). It was the fourth NASA conference of this type in the microgravity...
Topics: NASA Technical Reports Server (NTRS), CONFERENCES, MICROGRAVITY APPLICATIONS, CRYSTAL GROWTH,...
The objective of this study is to: (1) experimentally test the validity of the modeling predictions applicable to the magnetic damping of convective flows in electrically conductive melts as this applies to the bulk growth of solid solution semiconducting materials; and (2) assess the effectiveness of steady magnetic fields in reducing the fluid flows occurring in these materials during processing. To achieve the objectives of this investigation, we are carrying out a comprehensive program in...
Topics: NASA Technical Reports Server (NTRS), BRIDGMAN METHOD, CONVECTIVE FLOW, DAMPING, ELECTRICAL...
Complete and systematic ground-based experimental and theoretical analyses on the Physical Vapor Transport (PVT) of ZnSe and related ternary compound semiconductors have been performed. The analyses included thermodynamics, mass flux, heat treatment of starting material, crystal growth, partial pressure measurements, optical interferometry, chemical analyses, photoluminescence, microscopy, x-ray diffraction and topography as well as theoretical, analytical and numerical analyses. The...
Topics: NASA Technical Reports Server (NTRS), CHEMICAL ANALYSIS, CRYSTAL GROWTH, MORPHOLOGY, SEMICONDUCTORS...
A need exists for understanding precisely how particles move and interact in a fluid in the absence of gravity. Such understanding is required, for example, for modeling and predicting crystal growth in space where crystals grow from solution around nucleation sites as well as for any study of particles or bubbles in liquids or in experiments where particles are used as tracers for mapping microconvection. We have produced an exact solution to the general equation of motion of particles at...
Topics: NASA Technical Reports Server (NTRS), MICROGRAVITY, SPACE FLIGHT, SPACEBORNE EXPERIMENTS, PARTICLE...
In January 1992, the IML-1 FES experiment produced a set of classic experimental data and a 40 hour holographic "movie" of an ensemble of spheres in a fluid in microgravity. Because the data are in the form of holograms, we can study the three-dimensional distribution of particles with unprecedented detail by a variety of methods and for a wide variety of interests. The possession of the holographic movie is tantamount to having a complex experiment in space while working in an easily...
Topics: NASA Technical Reports Server (NTRS), MICROGRAVITY, CRYSTAL GROWTH, CONVECTION, SPACE PROCESSING,...
Convective flow in a Bridgman or float zone configuration significantly affects the interface shape and segregation phenomena. While the primary causative factor for this flow is buoyancy induced convection in an enclosed Bridgman melt, the presence of a free surface gives rise to surface tension driven flows in the floating zone processing of melts. It is of interest to curtail these flows in order to realize near quiescent growth conditions that have shown to result in crystals with good...
Topics: NASA Technical Reports Server (NTRS), BUOYANCY, CIRCULAR CYLINDERS, CONVECTION, CONVECTIVE FLOW,...
This paper provides an overview of the microgravity fluid physics and transport phenomena experiments planned for the International Spare Station. NASA's Office of Life and Microgravity Science and Applications has established a world-class research program in fluid physics and transport phenomena. This program combines the vast expertise of the world research community with NASA's unique microgravity facilities with the objectives of gaining new insight into fluid phenomena by removing the...
Topics: NASA Technical Reports Server (NTRS), FLUID DYNAMICS, TRANSPORT PROPERTIES, INTERNATIONAL SPACE...
The cryogenic fluid management technologies required for the exploration of the solar system can only be fully developed via space-based experiments. A dedicated spacecraft is the most efficient way to perform these experiments. This report documents the extended conceptual design of the COLD-SAT spacecraft, capable of meeting these experimental requirements. All elements, including the spacecraft, ground segment, launch site modifications and launch vehicle operations, and flight operations...
Topics: NASA Technical Reports Server (NTRS), FEASIBILITY ANALYSIS, CRYOGENICS, FLIGHT OPERATIONS, FLUID...
This document reports the one year science results for the important and highly successful Second United States Microgravity Laboratory (USML-2). The USML-2 mission consisted of a pressurized Spacelab module where the crew performed experiments. The mission also included a Glovebox where the crew performed additional experiments for the investigators. Together, about 36 major scientific experiments were performed, advancing the state of knowledge in fields such as fluid physics, solidification...
Topics: NASA Technical Reports Server (NTRS), MICROGRAVITY, SPACEBORNE EXPERIMENTS, SPACELAB, MICROGRAVITY...
The Liquid Motion Experiment (LME), designed to study the effects of liquid motion in rotating tanks, was flown on STS 84. LME was essentially a spin table that created a realistic nutation motion of scale-model tanks containing liquid. TWo spherical and two cylindrical transparent tanks were tested simultaneously, and three sets of such tanks were employed to vary liquid viscosity, fill level, and propellant management device (PMD) design. All the tanks were approximately 4.5 inches diameter....
Topics: NASA Technical Reports Server (NTRS), MICROGRAVITY, SPACE TRANSPORTATION SYSTEM, MICROGRAVITY...
Gravity modulation of an unbounded fluid layer with surface tension variations along its free surface is investigated. In parameter space of (wavenumber, Marangoni number) modulation has a destabilizing effect on the unmodulated neutral stability curve for large Prandtl number, Pr, and small modulation frequency, Omega, while a stabilizing effect is observed for small Pr and large Omega. As Omega yields infinity, the modulated neutral stability curves approach the unmodulated neutral stability...
Topics: NASA Technical Reports Server (NTRS), MICROGRAVITY, PRANDTL NUMBER, MARANGONI CONVECTION,...
This document includes information on all peer reviewed projects funded by the Office of Life and Microgravity Sciences and Applications, Life Sciences Division during fiscal year 1997. This document will be published annually and made available to scientists in the space life sciences field both as a hard copy and as an interactive internet web page.
Topics: NASA Technical Reports Server (NTRS), LIFE SCIENCES, MICROGRAVITY APPLICATIONS, BIBLIOGRAPHIES,...
This fiscal year (FY) 1997 annual report describes key elements of the NASA Microgravity Research Program (MRP) as conducted by the Microgravity Research Division (MRD) within NASA's Office of Life and Microgravity, Sciences and Applications. The program's goals, approach taken to achieve those goals, and program resources are summarized. All snapshots of the program's status at the end of FY 1997 and a review of highlights and progress in grounds and flights based research are provided. Also...
Topics: NASA Technical Reports Server (NTRS), AEROSPACE ENVIRONMENTS, SPACE MISSIONS, MICROGRAVITY...
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1998
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Hoover, Richard B.; Rozanov, Alexei Y.; Zhmur, S. I.; Gorlenko, V. M
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Investigations have been carried out on freshly broken, internal surfaces of the Murchison, Efremovka and Orgueil carbonaceous chondrites using Scanning Electron Microscopes (SEM) in Russia and the Environmental Scanning Electron Microscope (ESEM) in the United States. These independent studies on different samples of the meteorites have resulted in the detection of numerous spherical and ellipsoidal bodies (some with spikes) similar to the forms of uncertain biogenicity that were designated...
Topics: MICROGRAVITY, MATHEMATICAL MODELS, RESONANT FREQUENCIES, DAMPING, SPACE TRANSPORTATION SYSTEM,...
NASA's Microgravity Science and Applications Division (MSAD) sponsors a program that expands the use of space as a laboratory for the study of important physical, chemical, and biochemical processes. The primary objective of the program is to broaden the value and capabilities of human presence in space by exploiting the unique characteristics of the space environment for research. However, since flight opportunities are rare and flight research development is expensive, a vigorous ground-based...
Topics: NASA Technical Reports Server (NTRS), MICROGRAVITY APPLICATIONS, MICROGRAVITY, AEROSPACE...
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798
Dec 1, 1996
12/96
Dec 1, 1996
by
Arauz, Grigory L.; SanAndres, Lui
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Cryogenic damper seals operating close to the liquid-vapor region (near the critical point or slightly su-cooled) are likely to present two-phase flow conditions. Under single phase flow conditions the mechanical energy conveyed to the fluid increases its temperature and causes a phase change when the fluid temperature reaches the saturation value. A bulk-flow analysis for the prediction of the dynamic force response of damper seals operating under two-phase conditions is presented as:...
Topics: AEROSPACE ENVIRONMENTS, MICROGRAVITY APPLICATIONS, EMBRYOLOGY, REENTRY EFFECTS, CHICKENS, BONES,...
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Dec 1, 1996
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Dec 1, 1996
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Bansal, Narottam P
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Monoclinic celsian of Ba(0.75)Sr(0.25)Al2Si2O8 (BSAS-1) and B(0.85)Sr(O.15)Al2Si2O8 (BSAS-2) compositions have been synthesized from metal carbonates and oxides by solid state reaction. A mixture of BaCO3, SrCO3, Al2O3, and SiO2 powders was precalcined at approx. 900-940 C to decompose the carbonates followed by hot pressing at approx. 1300 C. The hot pressed BSAS-1 material was almost fully dense and contained the monoclinic celsian phase, with complete absence of the undesirable hexacelsian...
Topics: BONE MINERAL CONTENT, STELLAR EVOLUTION, PILOT PERFORMANCE, ABSORPTION SPECTROSCOPY, STUDENTS,...
This report presents the essential features and highlights of the 1996 Summer Faculty Fellowship Program at Ames Research Center and Dryden Flight Research Center in a comprehensive and concise form. Summary reports describing the fellow's technical accomplishments are enclosed. Of the 32 participating fellows, 27 were at Ames and 5 were at Dryden.
Topics: NASA Technical Reports Server (NTRS), BONE MINERAL CONTENT, POLYCYCLIC AROMATIC HYDROCARBONS,...
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Oct 1, 1996
10/96
Oct 1, 1996
by
Paielli, Russell A.; Erzberger, Hein
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The safety and efficiency of free flight will benefit from automated conflict prediction and resolution advisories. Conflict prediction is based on trajectory prediction and is less certain the farther in advance the prediction, however. An estimate is therefore needed of the probability that a conflict will occur, given a pair of predicted trajectories and their levels of uncertainty. A method is developed in this paper to estimate that conflict probability. The trajectory prediction errors...
Topics: MARANGONI CONVECTION, SLOTS, ALUMINUM, FINITE ELEMENT METHOD, INTERFACIAL TENSION, CAPILLARY FLOW,...
Diffusing-wave spectroscopy measurements show that ordinarily solid aqueous foams flow by a series of stick-slip avalanche-like rearrangements of neighboring bubbles from one tight packing configuration to another. Contrary to a recent prediction, the distribution of avalanche sizes do not obey a power-law distribution characteristic of self-organized criticality. This can be understood from a simple model of foam mechanics based on bubble-bubble interactions.
Topics: NASA Technical Reports Server (NTRS), BUBBLES, FOAMS, AQUEOUS SOLUTIONS, MELTING, MACROMOLECULES,...
The effects of imposed nonlinear oscillatory shear upon the onset of Marangoni-Bernard convection, as predicted by linear theory, in a layer of liquid with a deformable free surface were reported upon by Or and Kelly for small amplitude oscillations. Depending on the operating conditions, either stabilization or destabilization might occur. The aim of the current paper is to report the results for finite amplitude imposed oscillations so that the actual amount of stabilization or...
Topics: NASA Technical Reports Server (NTRS), CAPILLARY FLOW, MARANGONI CONVECTION, DEFORMATION, CONVECTIVE...
In this paper we present results from experiments with a system consisting of two immiscible fluid layers in rectangular and annular geometries, driven by a vertical temperature gradient. Time-dependent variations in the type of coupling observed between the two layers are described and characterized.
Topics: NASA Technical Reports Server (NTRS), RAYLEIGH-BENARD CONVECTION, TEMPERATURE GRADIENTS, TIME...
The NASA Microgravity Science and Applications Division (MSAD) sponsors science experiments on a variety of microgravity carriers, including sounding rockets, drop towers, parabolic aircraft, and Orbiter missions. The MSAD sponsors the Space Acceleration Measurement System (SAMS) to support microgravity science experiments with acceleration measurements to characterize the microgravity environment to which the experiments were exposed. The Principal Investigator Microgravity Services project at...
Topics: NASA Technical Reports Server (NTRS), MICROGRAVITY APPLICATIONS, MIR SPACE STATION, SPACE...
The surface tension driven convection experiment-2 (STDCE-2) was conducted onboard the U.S. Microgravity Laboratory (USML)-2 Spacelab which was launched on October 20, 1995. The main objectives of the experiment was to study oscillatory thermocapillary flows in microgravity. Thermocapillary flows were generated in cylindrical test chambers filled with 2 centistokes silicone oil. Six modules were used to study three different chamber diameters and two different heating modes. Tests with both...
Topics: NASA Technical Reports Server (NTRS), CAPILLARY FLOW, CYLINDRICAL CHAMBERS, FLOW DISTRIBUTION, FLOW...
A computational study of thermally-driven convection in multilayered fluid structures will be performed to examine the effect of interactions among deformable fluid-fluid interfaces on the structure of time-dependent flow in these systems. Multilayered fluid structures in two models configurations will be considered: the differentially heated rectangular cavity with a free surface, and the encapsulated cylindrical liquid bridge. An extension of a numerical method developed as part of our recent...
Topics: NASA Technical Reports Server (NTRS), TIME DEPENDENCE, CAVITY FLOW, MICROGRAVITY APPLICATIONS,...
We performed a series of experiments on 0.518 millimeter PMMA spheres suspended in an index matching mixture of decalin and tetralin the microgravity environment provided by the Shuttle Columbia on mission STS-73. The samples ranged in concentration from 0.49 to 0.62. volume fraction (phi) of spheres, which covers the range in which liquid, coexistence, solid and glass phases are expected from Earth bound experiments. Light scattering was used to probe the static structure, and the particle...
Topics: NASA Technical Reports Server (NTRS), CRYSTAL GROWTH, LIGHT SCATTERING, GRAVITATIONAL EFFECTS,...
This program investigates the fluid dynamics and simultaneous solidification of molten solder droplets impacting on a flat substrate. The problem of interest is directly relevant to the printing of microscopic solder droplets in surface mounting of microelectronic devices. The study consists of a theoretical and an experimental component. The theoretical work uses axisymmetric Navier-Stokes models based on finite element techniques. The experimental work is performed in microgravity to allow...
Topics: NASA Technical Reports Server (NTRS), DROPS (LIQUIDS), SOLDERS, SUBSTRATES, GRAVITATIONAL EFFECTS,...
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159
Sep 1, 1996
09/96
Sep 1, 1996
by
Schachter, Jonatha
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The goal of this investigation was to use the improved positions of the Einstein Slew Survey to help identify sources in background fields and; the North Ecliptic Pole region of Ginga data. Our main progress has been on the former of these two goals. In July, 1996, we performed a detailed search of the background regions at Leicester, UK. Only one of the Slew/Ginga fields had a high enough count rate (greater than 3 LAC cts s(exp -1)) for an unambiguous detection, given the known fluctuations...
Topics: ZIRCONATES, AMPOULES, CRYSTALLIZATION, ZIRCONIUM COMPOUNDS, METAL FLUORIDES, OPTICAL FIBERS,...
We present a brief, preliminary account of the interpretation of dynamic light scattering from fractal colloidal gels. For small scattering angles, and for high initial colloid particle volume fractions, the correlation functions exhibit arrested decay, reflecting the non-ergodic nature of these systems and allowing us to directly determine the elastic modulus of the gels. For smaller initial volume fractions, the correlation functions decay completely. In all cases, the initial decay is not...
Topics: NASA Technical Reports Server (NTRS), MODULUS OF ELASTICITY, GELS, COLLOIDS, FRACTALS, LIGHT...
Stability analysis of thermocapillary convection in rectangular cavities is performed using direct numerical simulation. The influence of the Reynolds number (Re), the fluid Prandtl number (Pr) and cavity aspect ratio (Ar) on the motion is investigated. Neutral stability curves for transition to time-dependent convection are delineated in the Re-Ar plane for fluids with Pr=1.0, 4.4, 6.78, and 10. Several interesting features of these diagrams are discussed. One important conclusion is that...
Topics: NASA Technical Reports Server (NTRS), CAPILLARY FLOW, TIME DEPENDENCE, STABILITY TESTS, PRANDTL...
