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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Role of liquid-liquid phase separation-induced surface tension changes in cloud droplet activation
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Fire Hazards from Aerosol Cans: Exploring the Dependency on Surface Tension and Viscosity
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High-Fidelity Parametric Study of Surface Tension and Viscosity Effects in Immiscible Rayleigh-Taylor Mixing
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ASTRONAUTICS INFORMATION TRANSLATION NO. 16 SURFACE TENSION AND HEAT VAPORIZATION OF METALS
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A survey of current developments in surface tension devices for propellant acquisition
Spacecraft propellant expulsion systems, comparing capillary with conventional techniques
A survey of current developments in surface tension devices for propellant acquisition
Spacecraft propellant expulsion systems, comparing capillary with conventional techniques
Surface tension devices for orientation and control of liquid propellants in a low gravity environment
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Surface tension, density, and volume change on melting of Al2O3 systems, Cr2O3, and Sm2O3.
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Generalized van der Waals theories for surface tension and interfacial width.
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SS/RCS surface tension propellant acquisition/expulsion tankage technology
The analysis, design, fabrication, and testing of a propellant tank that satisfies the requirements of the space shuttle is presented. This mission presents very stringent and sometimes conflicting requirements. A compartmented-tank device was developed and various ground and drop tower test techniques were employed to verify the design using both subscale and full-scale hardware. Performance was established with scale models and further substantiation was obtained with the full-scale tankage. Fabrication, acceptance, fill and drain, inspection, and other ground handling procedures were developed.
Surface tension induced convection in encapsulated liquid metals in a microgravity environment. Experiment MA-041
The experiment was designed to detect possible convection caused by a steplike compositional variation in a liquid metal in a microgravity environment. Wetting and nonwetting ampoules were used to try to determine the extent of the stirring effects if they were present. Since stirring effects can be caused by temperature gradients, the temperature gradients were minimized. Steplike compositional variation was created by pressure bonding a lead-0.05 atom percent gold alloy to pure lead. Two diffusion temperatures (923 K and 723 K) were used; if no stirring effects were present, it was hoped that the liquid diffusion parameters for gold in lead could be obtained. Two identifical experimental arrangements were used to compare the transport mechanisms of gold in liquid lead in unit gravity and microgravity environments.
Revised international representations for the viscosity of water and steam and new representations for the surface tension of water
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Convection due to surface-tension gradients
The use of dimensionless parameters to study fluid motions that could occur in a reduced-gravity environment is discussed. The significance of the Marangoni instability is considered, and the use of dimensionless parameters to investigate problems such as thermo and diffusocapillary flows is described. Characteristics of fluid flow in space are described, and the relation and interaction of motions due to capillarity and buoyancy is examined.
Surface-tension induced instabilities: Effects of lateral boundaries
Convection in circular and rectangular cylinders is analyzed. The governing equations and boundary conditions are formulated, linear and nonlinear stability theory are considered, and the physical implications of the theory are discussed.
Surface tension and contact angles: Molecular origins and associated microstructure
Gradient theory converts the molecular theory of inhomogeneous fluid into nonlinear boundary value problems for density and stress distributions in fluid interfaces, contact line regions, nuclei and microdroplets, and other fluid microstructures. The relationship between the basic patterns of fluid phase behavior and the occurrence and stability of fluid microstructures was clearly established by the theory. All the inputs of the theory have molecular expressions which are computable from simple models. On another level, the theory becomes a phenomenological framework in which the equation of state of homogeneous fluid and sets of influence parameters of inhomogeneous fluids are the inputs and the structures, stress tensions and contact angles of menisci are the outputs. These outputs, which find applications in the science and technology of drops and bubbles, are discussed.
Effects of rotation and magnetic field on the onset of convective instability in a liquid layer due to buoyancy and surface tension
Thermocapillary stability characteristics of a horizontal liquid layer heated from below rotating about a vertical axis and subjected to a uniform vertical magnetic field are analyzed under a variety of thermal and electromagnetic boundary conditions. Results based on analytical solutions to the pertinent eigenvalue problems are discussed in the light of earlier work on special cases of the more general problem considered here to show in particular the effects of the heat transfer, nonzero curvature and gravity waves at the two-fluid interface. Although the expected stabilizing action of the Coriolis and Lorentz force fields in this configuration are in evidence the optimal choice of an appropriate range for the relevant parameters is shown to be critically dependent on the interfacial effects mentioned above.
Enhanced erythrocyte suspension layer stability achieved by surface tension lowering additives
In connection with a fractionation procedure involving the separation of particles, a dilute suspension of these particles in a liquid is carefully layered on a dense liquid. Under ideal conditions, the suspension forms a zone of finite thickness with a 'sharp' interface between the suspension layer and the supporting liquid. Under an applied field, e.g., gravitational or electrical, the particles in the suspension layer migrate to form different layers according to their size and/or density or according to their electrophoretic mobilities. However, in many cases the ideal conditions necessary for the fractionation process are not obtained. Many studies have been conducted to explore the reasons for suspension layer 'instability'. The present investigation represents an extension of a study conducted by Omenyi et al. (1981). An electrostatic repulsion-van der Waals mechanism was used to study the stability of fixed erythrocyte suspensions layered on a D2O cushion.