Liquid inflow to initially empty, hemispherical ended cylinders during weightlessness
Liquid-vapor interface stability during liquid inflow in cylindrical tank during weightlessness
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Liquid-vapor interface stability during liquid inflow in cylindrical tank during weightlessness
Nuclear sampling technique for measuring propellant mass in cylindrical tanks aboard orbiting space vehicles, discussing nuclear monochromatic gamma and X ray sources
Coupled oscillations of sloshing liquid in elastic rectangular and cylindrical tank, noting frequency changes due to level and container configuration
Behavior of sloshing liquid in cylindrical tanks subject to sudden reduction in axial acceleration, noting center of gravity shift as function of Froude number
Coupled oscillations of sloshing liquid in elastic rectangular and cylindrical tank, noting frequency changes due to level and container configuration
Circular baffle mounted above flat-bottomed cylindrical tank outlet, discussing effect on remaining tank fluid volume and flow behavior under low gravity conditions
Fluid motion in cylindrical tank with arbitrary sector annular cross section subjected to harmonic longitudinal excitation
Liquid propellant sloshing in tilted axisymmetric cylindrical tanks for space shuttle applications
Measurement of liquid oscillation frequencies in tilted cylindrical tanks of five different cross section shapes
Two cylindrical tanks with piston bladders and associated components for automatic filling and emptying use liquid inventory readout devices in control of water flow. Unit provides for adaptive water collection, storage, and dispensation in weightlessness environment.
An experimental investigation was conducted to study the relative effectiveness of various outlet baffles in reducing liquid residuals resulting from the draining of hemispherically ended cylindrical tanks in a weightless environment. Three different baffles were employed. The relative effectiveness of each baffle was determined by comparing the results obtained, in the form of liquid residuals, with results for an unbaffled tank. Data indicate that all the baffles tested reduced residuals. Reductions betweem 10 and 60 percent were obtained, depending on baffle geometry and outlfow Weber number.
An experimental investigation was conducted to study liquid-vapor interface behavior and subsequent vapor ingestion in a flat-bottomed cylindrical tank following a single-step throttling in outflow rate in a weightless environment. A throttling process in which the final Weber number was one-tenth of the initial Weber number tended to excite large-amplitude symmetric slosh, with the amplitude generally increasing as initial Weber number increased. As expected, liquid residuals were lower than those obtained without throttling and, for moderate values of initial Weber number, could be adequately predicted by assuming that all draining took place at the final Weber number. At large values of Weber number, residuals tended to be lower than this predicted value.
The elastic instability of an internally-pressurized cylindrical tank with a torispherical head is investigated using a triangular, doubly curved, thin-shell finite element. The formulation of the finite element, which is based upon cubic displacement functions and a modified principle of potential energy, is first described. Then, the element is verified by comparing numerical results for the linear, stable analysis to alternative solutions for the same problem. The subsequent instability investigation includes the solution of the linearized problem of equilibrium bifurcation, that is, of the classical eigenvalue problem, and a general nonlinear analysis, based on tracing the nonlinear load-displacement path. The critical pressure, obtained with use of the general nonlinear analysis, agrees closely with an experimental result as well as with a numerical solution stemming from an axisymmetric formulation.
An experimental investigation was conducted to study the phenomenon of vapor ingestion during the draining of a scale model, hemispherically bottomed cylindrical tank in a low-gravity environment. Where possible, experimental results are compared with previously obtained numerical predictions. It was observed that certain combinations of Weber and Bond number resulted in draining-induced axisymmetric slosh motion. The periods of the slosh waves were correlated with the square root of the draining parameter, the ratio (Weber number)/(Bond number plus one), as was the quantity of liquid remaining in the tank when vapor was ingested into the outlet line.
An experimental program was conducted to examine the liquid flow patterns that result from the axial jet mixing of ethanol in 10-centimeter-diameter cylindrical tanks in weightlessness. A convex hemispherically ended tank and two Centaur liquid-hydrogen-tank models were used for the study. Four distinct liquid flow patterns were observed to be a function of the tank geometry, the liquid-jet velocity, the volume of liquid in the tank, and the location of the tube from which the liquid jet exited.
Since oxygen makes up 86% of the total mass of propellants which would normally have been brought up from the earth to LEO, considerable savings are available if this oxygen can be obtained from the moon for little Delta-V penalty. This paper presents a scenario in which 400 T/yr of LOX is delivered to LEO, with the ability for upgrading to 5000 T/yr. In this scenario, cylindrical tanks of liquid oxygen with a mass of 500 kg are launched from the lunar surface by a mass driver and rendezvous with a collection station in a 100-km lunar orbit. The oxygen is removed from each tank and placed into a tanker OTV which later will transfer from low lunar orbit to LEO with an aerobraking maneuver. Launch requirements for aerobraked chemical OTVs using earth oxygen are compared to those using lunar oxygen.
Special tooling alines and holds internally-stiffened large-diameter cylindrical parts for welding. Alinement brackets attached to strengthening fins on insides of cylindrical tank sections. Jackscrews on brackets raised or lowered to eliminate mismatches between adjacent sections. Tooling substantially reduces costs while allowing more precise control and improved quality.
A computer program aimed at the phase separation between gas and liquid at zero gravity, induced by vortex motion, is developed. It utilizes an explicit solution method for a set of equations describing rotating gas-liquid flows. The vortex motion is established by a tangential fluid injection. A Lax-Wendroff two-step (McCormack's) numerical scheme is used. The program can be used to study the fluid dynamical behavior of the rotational two-phase fluids in a cylindrical tank. It provides a quick/easy sensitivity test on various parameters and thus provides the guidance for the design and use of actual physical systems for handling two-phase fluids.