Supercritical bipropellant droplet combustion
Fuel droplets burning at pressures sufficient to reach critical temperature under zero gravity conditions in free fall apparatus
Dominicis, D. P.↗
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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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A class of high energy, close approach trajectories within the three-body problem
High energy close approach trajectories within planar free fall three body problem, using perturbation theory
Burggraf, O. R.↗
Wind velocity probing device and method Patent
Free-fall body for obtaining wind velocity profiles by radar tracking
Stengel, R. F.↗
Radiative Extinguishment of Diffusion Flames at Zero Gravity
Radiative heat transfer effects on small fires in zero gravity spacecraft and free falling chamber environments from diffusion flame models
Bonne, U.↗
Mass center estimation in spinning drag-free satellites
Analog mass center estimator for spinning drag- free orbiting satellite, using free-falling proof mass shielded from external forces inside satellite cavity as reference
Powell, J. D.↗
Reference earth orbital research and applications investigations (blue book). Volume 6: Materials sciences and manufacturing
The development of commercial manufacturing and research activities in space is discussed. The capability is to be installed in space stations in order to exploit the extended free fall which makes many novel manipulations of materials possible and alters the behavior of certain chemical and physical processes. The broad objectives are: (1) to develop technical basis required for commercial use of manned space facilities, (2) to provide indirect economic benefits by exploiting advantages of space laboratory facilities to solve critical experimental problems, and (3) to initiate manufacturing operations in space by private enterprise for commercial purposes and by agencies of the Government for public purposes.
Source record↗
Transient analysis of an IVHM grapple impact test
A lumped mass model was used to represent the impact condition between a fuel duct and an IVHM in-vessel fuel handling machine. The nonlinear effects of a Bellville spring and the free fall impact of the fuel duct on the IVHM were included. The purpose of the tests was to determine the loads on the fuel duct due to the impact. A comparison between experimental and theoretical results is presented.
Hill, R. G.↗
Lorentz transformations in the presence of a uniform gravitational field.
This article describes a Lorentz-like transformation between a fixed frame and an inertial frame that is free falling due to the presence of a uniform gravitation field. The application to the clock paradox problem and some connections with similar works are also discussed.
Broucke, R.↗
Experiments leading to the production of new glasses in space.
Report on an experimental program aimed at verifying proposed concepts of glassmaking in space from substances that to date have been observed only in a crystalline condition. A summary is presented on the results of experiments conducted by laser melting of ceramic rods of chosen composition and allowing the droplets ejected from the spinning rod to cool by free falling. This technique should permit an early evaluation of which compositions are most suitable for subsequent more expensive space experiments.
Happe, R. A.↗
N-body U and K matrix program
Computer program was devised to compute free-fall trajectories of satellites, allowing for injection errors and midcourse velocity perturbations. Program consists of trajectory perturbing program and N-body integrating conic program which can also be used as 2-body patch conic program.
Setter, R. N.↗
S band transponder experiment
It is reported that this experiment measures the lunar gravitational field, which in turn provides information on the distribution of lunar mass and its correlation with surface features such as craters, mountains, and maria. The lunar gravitational field is measured by observing the dynamical motion of spacecraft in free-fall orbits. Effective detection of mass variations is greatly enhanced by low-altitude trajectories, such as the eccentric orbits during revolutions 3 to 16 of the Apollo 16 spacecraft and the 11 km periapsis of the Apollo 16 subsatellite during May 1972. The observational data are the precise earth-based radio tracking measurements initially used for real-time navigation.
Sjogren, W. L.↗
Zero Gravity Facility for space vehicle fluid systems research.
Review of the major features and characteristics of the 5- to 10-second Zero Gravity Facility of the NASA Lewis Research Center. The facility consists primarily of a vertical (155 m) vacuum chamber wherein a variety of free-fall (weightless) experiments can be performed.-
Petrash, D. A.↗
Atmosphere-entry behavior of a modular, disk-shaped, isotope heat source.
The authors have studied the entry and impact behavior of an isotope heat source for space nuclear power that disassembles into a number of modules which would enter the earth's atmosphere separately if a flight aborted. These modules are disk-shaped units, each with its own reentry heat shield and protective impact container. In normal operation, the disk modules are stacked inside the generator, but during a reentry abort they separate and fly as individual units of low ballistic coefficient. Flight tests at hypersonic speeds have confirmed that a stack of disks will separate and assume a flat-forward mode of flight. Free-fall tests of single disks have demonstrated a nominal impact velocity of 30 m/sec at sea level for a practical range of ballistic coefficients.
Vorreiter, J. W.↗
Experiments leading to the production of new glasses in space
A number of oxide compositions were prepared as ceramic rods which were melted in a CO2 laser beam while spinning. The molten droplets which were spun off the rods were allowed to free-fall cool. Many of the compositions selected were obtained as glasses of never-before-reported composition. It can be concluded that it is possible to obtain spherules of glasses from oxide compositions that have never before been obtained in the 'glassy state.' These initial experiments encourage future attempts to prepare larger sized glass boules by containerless melting and cooling in space or in appropriately simulated space.
Happe, R. A.↗
Flight tests of Viking parachute system in three Mach number regimes. 1: Vehicle description, test operations, and performance
Flight qualifications for parachutes were tested on full-scale simulated Viking spacecraft at entry conditions for the Viking 1975 mission to Mars. The vehicle was carried to an altitude of 36.6 km for the supersonic and transonic tests by a 980.000 cu m balloon. The vehicles were released and propelled to test conditions with rocket engines. A 117,940 cu m balloon carried the test vehicle to an altitude of 27.5 km and the conditions for the subsonic tests were achieved in free fall. Aeroshell separation occurred on all test vehicles from 8 to 14 seconds after parachute deployment. This report describes: (1) the test vehicle; (2) methods used to insure that the test conditions were achieved; and (3) the balloon system design and operations. The report also presents the performance data from onboard and ground based instruments and the results from a statistical trajectory program which gives a continuous history of test-vehicle motions.
Lundstrom, R. R.↗
Titan/Centaur T/C-1 post flight evaluation report
The first Titan/Centaur launch vehicle, TC-1, was launched from the Eastern Test Range Complex 41 at 09:48:01.46 hours Eastern Daylight Time on February 11, 1974. The vehicle carried a dynamic mass model of the Viking spacecraft and a SPHINX spacecraft, intended to study high voltage interactions in space. This launch was a Proof Flight of a vehicle con- figuration integrating the Air Force Titan booster and the NASA Centaur upper stage. It also was the first flight of the Centaur Standard Shroud developed for the Titan/Centaur. The countdown for the launch proceeded normally except for an additional 45 minute hold which was required to resolve a question concerning interpretation of booster hydraulic system data. The launch window opened at 09:03:00 hours Eastern Daylight Time. The vehicle was launched o on a flight azimuth of 105°. The Titan boost phase of flight was satisfactory. Solid Motor operation, Stage I and Stage II operation were normal. Venting of the Centaur Standard Shroud during ascent was successful and shroud separation and jettison was accomplished without incident. At the completion of the Titan Stage II burn, the Centaur successfully separated from the Titan. At this time, the Centaur main engines were sequenced through the first planned starting cycle but failed to achieve steady state operation. The vehicle flight control system, not sensing vehicle acceleration, commanded engine shutdown, and recycled, as programmed, through a back-up engine start attempt. The second engine start attempt was also unsuccessful. The flight control system then placed the vehicle in a coast-phase mode and the vehicle continued downrange in free fall. The vehicle was destroyed by Range Safety when the impact point was approximately 2200 nautical miles downrange, 12 minutes, 28.5 seconds after liftoff.
S. V. Szabo, Jr.↗
Study on processing immiscible materials in zero gravity
An experimental investigation was conducted to evaluate mixing immiscible metal combinations under several process conditions. Under one-gravity, these included thermal processing, thermal plus electromagnetic mixing, and thermal plus acoustic mixing. The same process methods were applied during free fall on the MSFC drop tower facility. The design is included of drop tower apparatus to provide the electromagnetic and acoustic mixing equipment, and a thermal model was prepared to design the specimen and cooling procedure. Materials systems studied were Ca-La, Cd-Ga and Al-Bi; evaluation of the processed samples included the morphology and electronic property measurements. The morphology was developed using optical and scanning electron microscopy and microprobe analyses. Electronic property characterization of the superconducting transition temperatures were made using an impedance change-tuned coil method.
Reger, J. L.↗
Clumping of interstellar grains during formation of the primitive solar nebula
The author has previously shown that a considerable amount of clumping of interstellar grains is likely to take place during the free-fall collapse phase of an interstellar cloud which is forming the primitive solar nebula, with the assumption of sonic turbulence in the gas. The original estimate involved the crude assumption of hierarchal amalgamation of the grains upon collision. A Monte Carlo simulation of this process confirmed the general features of the results, but it was further found that the introduction of a low sticking probability reduced the size of the lumps quite significantly. A more realistic calculation was therefore carried out in which it was assumed that clumps of grains would tend to stick together if their collisions were approximately head-on, but that they would tend to fragment into smaller pieces if the collisions were more tangential. For typical values of the amalgamation parameter, this tends to spread the mass of the interstellar grains over a wide range of clump sizes, ranging from individual grains to objects in the millimeter or centimeter size.
Cameron, A. G. W.↗