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in subjects: "Space Vehicles"

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Development of a High Velocity Solid Particle Launcher for Laboratory Erosion Studies. [Reentry Vehicle Heat Shields]

A solid particle launcher for laboratory erosion studies has been developed and successfully demonstrated. Performance of the launcher is predicted by a two-dimensional, time-dependent theoretical analysis to within the experimental uncertainty. The present device accelerates 100 μm diameter glass spheres to velocities of 2.1+/- 0.6 km/sec. The system is safe, reliable, and has a test repetition of about 2 shots/hour.

Date: March 1, 1975

Creator: Aeschliman, D. P.; Mulac, A. J.; Guzman, J. A.; Eaton, R. R. & Fox, R. L.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Design and operation of an inert gas facility for thermoelectric generator storage

While the flight hardware is protected by design from the harsh environments of space, its in-air storage often requires special protection from contaminants such as dust, moisture and other gases. One of these components, the radioisotope thermoelectric generator (RTG) which powers the missions, was deemed particularly vulnerable to pre-launch aging because the generators remain operational at core temperatures in excess of 1000 degrees centigrade throughout the storage period. Any oxygen perm… more

Date: January 1, 1990

Creator: Goebel, C. J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Physics of antimatter-matter reactions for interstellar propulsion

At the stage of the antiproton-nucleon annihilation chain of events relevant to propulsion the annihilation produces energetic charged pions and gamma rays. If annihilation occurs in a complex nucleus, protons, neutrons, and other nuclear fragments are also produced. The charge, number, and energy of the annihilation products are such that annihilation rocket engine concepts involving relatively low specific impulse (I/sub sp/ approx. = 1000 to 2000 s) and very high I/sub sp/ (3 x 10/sup 7/ s) … more

Date: August 22, 1986

Creator: Morgan, D.L. Jr.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Computational determination of ballistic limits for a simple Whipple bumper shield

A series of numerical simulations has been performed using the multi-dimensional hydrodynamics code CTH to computationally determine a ballistic limit for a Whipple bumper shield. The ballistic limit is generally characterized as a critical diameter such that particle diameters greater than the ballistic limit will generate debris clouds that will penetrate the rear wall and particle diameters less than the ballistic limit will not. The particular shield design used for these analyses is define… more

Date: January 1, 1991

Creator: Hertel, E.S.; Chhabildas, L.C.; Yarrington, L. (Sandia National Labs., Albuquerque, NM (United States)) & Hill, S.A. (National Aeronautics and Space Administration, Huntsville, AL (United States). George C. Marshall Space Flight Center)

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Princeton Plasma Physics Laboratory:

This paper discusses progress on experiments at the Princeton Plasma Physics Laboratory. The projects and areas discussed are: Principal Parameters Achieved in Experimental Devices, Tokamak Fusion Test Reactor, Princeton Large Torus, Princeton Beta Experiment, S-1 Spheromak, Current-Drive Experiment, X-ray Laser Studies, Theoretical Division, Tokamak Modeling, Spacecraft Glow Experiment, Compact Ignition Tokamak, Engineering Department, Project Planning and Safety Office, Quality Assurance and … more

Date: January 1, 1986

Creator: Phillips, C.A. (ed.)

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Advanced nuclear rocket engine mission analysis

The use of a derivative of the NERVA engine developed from 1955 to 1973 was evluated for potential application to Air Force orbital transfer and maneuvering missions in the time period 1995 to 2020. The NERVA stge was found to have lower life cycle costs (LCC) than an advanced chemical stage for performing low earth orbit (LEO) to geosynchronous orbit (GEO0 missions at any level of activity greater than three missions per year. It had lower life cycle costs than a high performance nuclear elect… more

Date: December 1, 1987

Creator: Ramsthaler, J.; Farbman, G.; Sulmeisters, T.; Buden, D. & Harris, P.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Activated recombinative desorption: a potential component in mechanisms of spacecraft glow

The concept of activated recombination of atomic species on surfaces is capable of explaining the production of vibrationally and translationally excited desorbed molecular species. Equilibrium statistical mechanics predicts that the molecular quantum state distributions of desorbing molecules is a function of only the surface temperature when the adsorption probability is unity and independent of initial collision conditions. In most cases though the adsorption probability is dependent upon in… more

Date: January 1, 1985

Creator: Cross, J.B.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Quantitative analysis of bidirectional electron fluxes within coronal mass ejections at 1 AU

The solar wind electron heat flux is carried primarily by suprathermal halo'' electrons beamed antisunward along the interplanetary magnetic field (IMF), indicating magnetic connection to the Sun only in one direction. However, electron observations at 1 AU show that counterstreaming halo beams, suggesting closed magnetic structures, prevail within coronal mass ejections (CMEs). These structures might be magnetic tongues'', tied to the Sun at both ends, magnetically detached plasmoids, or compl… more

Date: January 1, 1991

Creator: Phillips, J.L.; Gosling, J.T.; McComas, D.J.; Bame, S.J. & Feldman, W.C.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Growth of single crystals of mercuric iodide (HgI/sub 2/) in spacelab III

Continued development of a system designed to grow crystals by physical vapor transport in the environment of Spacelab III will be described, with special emphasis on simulation of expected space conditions, adjustment of crystal growth parameters, and on board observation and control of the experiment by crew members and ground personnel. A critical factor in the use of mercuric iodide for semiconductor detectors of x-rays and gamma-rays is the crystalline quality of the material. The twofold … more

Date: January 1, 1981

Creator: Van Den Berg, L. & Schnepple, W. F.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Light Weight Radioisotopic Heater Unit (LWRHU) production for the Galileo Mission

The Light Weight Radioisotopic Heater Unit (LWRHU) is a /sup 238/PuO/sub 2)minus/ fueled heat source designed to provide a thermal watt of power for space missions. The LWRHU will be used to maintain the temperature of various components on the spcaecraft at the required level. The heat source consists of a /sup 238/PuO/sub 2/ fuel pellet, a Pt-30Rh capsule, a pyrolytic graphite insulator, and a woven graphite aeroshell assembly. Los Alamos National Laboratory (LANL) has fabricated 134 heater u… more

Date: April 1, 1988

Creator: Rinehart, G.H.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Demonstration of rapid and sensitive module leak certification for space station freedom

A leak detection and quantification demonstration using perflurocarbon tracer (PFT) technology was successfully performed at the NASA Marshall Space Flight Center on January 25, 1991. The real-time Dual Trap Analyzer (DTA) at one-half hour after the start of the first run gave an estimated leak rate of 0.7 mL/min. This has since been refined to be 1.15 {plus minus} 0.09 mL/min. The leak rates in the next three runs were determined to be 9.8 {plus minus} 0.7, {minus}0.4 {plus minus} 0.3, and 76 … more

Date: March 1, 1991

Creator: Dietz, R. N. & Goodrich, R. W.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Nuclear thermal rocket clustering: 1, A summary of previous work and relevant issues

A general review of the technical merits of nuclear thermal rocket clustering is presented. A summary of previous analyses performed during the Rover program is presented and used to assess clustering in the context of projected Space Exploration Initiative missions. A number of technical issues are discussed including cluster reliability, engine-out operation, neutronic coupling, shutdown core power generation, shutdown reactivity requirements, reactor kinetics, and radiation shielding. 7 refs… more

Date: July 14, 1991

Creator: Buksa, J.J. & Houts, M.G.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Thermal vacuum life test facility for radioisotope thermoelectric generators

In the late 1970's, the Department of Energy (DOE) assigned Monsanto Research Corporation, Mound Facility, now operated by EG G Mound Applied Technologies, the responsibility for assembling and testing General Purpose Heat Source (GPHS) radioisotope thermoelectric generators (RTGs). Assembled and tested were five RTGs, which included four flight units and one non-flight qualification unit. Figure 1 shows the RTG, which was designed by General Electric AstroSpace Division (GE/ASD) to produce 285… more

Date: January 1, 1990

Creator: Deaton, R. L.; Goebel, C. J. & Amos, W. R.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

The Gevaltig: An inertial fusion powered manned spacecraft design for outer solar system missions

The Gevaltig is an inertial fusion powered rocket engine capable of manned missions to other planets with round trip mission times as low as 100 days. The Gevaltig design was previously described for a mission to Mars. This effort defines the spacecraft components in terms of mass and presents a mission analysis for a manned trip to Titan, a moon of Saturn. The Gevaltig component masses are provided as a function of fuel pellet ignition frequency. These variable mass components include the fuel… more

Date: October 1, 1989

Creator: Murray, K.A.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

SNAP 19 Pioneer F and G. Final report

The generator developed for the Pioneer mission evolved from the SNAP 19 RTG's launched aboard the NIMBUS III spacecraft. In order to satisfy the power requirements and environment of earth-escape trajectory, significant modifications were made to the thermoelectric converter, heat source, and structural configuration. Specifically, a TAGS-2N thermoelectric couple was designed to provide higher efficiency and improved long term power performance, and the electrical circuitry was modified to yie… more

Date: June 1, 1973

Item Type: Report

Partner: UNT Libraries Government Documents Department

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SNAP 19 Viking Program. Bimonthly Technical Progress Report, December 1979-January 1980

Power system performance data for Pioneer 10 and Pioneer Saturn (initially designated Pioneer 11) were monitored through the reporting period. The estimated RTG system net power was 115 watts for Pioneer 10 and 116 watts for Pioneer Saturn. The telemetry signal quality from both spacecraft systems remains satisfactory.

Date: January 1, 1980

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Thermoelectric generator testing and RTG degradation-mechanisms evaluation. Progress report No. 32

Thermal conductivity tests of the older p-type were terminated after 22,000 hours. The n-type selenide legs after 8000 hours continue to show agreement with the 3M Company published data. In the ingradient testing after 10,200 hours the n-legs show comparable performance to the reported 3M data. A new station for ingradient performance testing of the new design p-type legs with the Astroquartz/slurry wrap was nearly completed. Weight loss testing of the new design p-type TPM217 (no partition) w… more

Date: October 1, 1979

Creator: Lockwood, A.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Prospects for space arms control

At the recent Wyoming Ministerial, US Secretary of State Baker and Soviet Foreign Minister Shevardnadze signed a memorandum of understanding on a bilateral verification experiment and data exchange related to a prohibition on chemical weapons, an agreement on advance notification of certain strategic exercises, and an umbrella agreement on START trial verification and stability measures. Despite these substantive achievements in high priority areas for the United States and the Soviet Union, me… more

Date: January 1, 1989

Creator: Pilat, J.F.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Heat pump augmented radiators for spacecraft thermal management

Because future space missions will require heat rejection subsystems having megawatt capacity, the development of lightweight heat rejection techniques is desirable. Closed systems for waste heat rejection in space are radiative and their capacity is proportional to the fourth power of absolute temperature. Reductions in the surface area and therefore, in the mass of a space radiator are possible by increasing the heat rejection temperature above the temperature of the thermal source. One propo… more

Date: January 1, 1988

Creator: Merrigan, M.A. & Reid, R.S.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Reentry thermal testing of a general purpose heat source fueled clad

A General Purpose Heat Source (GPHS) module was exposed to heat treatments simulating an isothermal prelaunch condition, followed by thermal pulses corresponding to atmospheric reentry. Helium release rates were determined during each heating and modeled after simple diffusion theory. Following the tests, the module was examined metallurgically with no evidence of swelling of the cladding nor degradation of the fuel.

Date: March 1, 1982

Creator: Peterson, D. E. & Frantz, C. E.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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General-purpose heat source project and space nuclear safety fuels program. Progress report, February 1980

This formal monthly report covers the studies related to the use of /sup 238/PuO/sub 2/ in radioisotopic power systems carried out for the Advanced Nuclear Systems and Projects Division of the Los Alamos Scientific Laboratory. The two programs involved are: General-Purpose Heat Source Development and Space Nuclear Safety and Fuels. Most of the studies discussed here are of a continuing nature. Results and conclusions described may change as the work continues. Published reference to the results… more

Date: May 1, 1980

Creator: Maraman, W.J. (comp.)

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Proceedings of the workshop on the modification of the upper atmosphere by Satellite Power System (SPS) propulsion effluents

Results of a workshop held in June 1979, to identify research needs for evaluating environmental impacts on the upper atmosphere (here defined as greater than 70 km) due to Satellite Power System (SPS) transport, i.e., propulsion and reentry are presented. The substantial injections of water and hydrogen therefrom may lead to global-scale regions of reduced ionization in the ionospheric F-Region that may have a serious impact on worldwide HF radio communications; and the resulting possibly sign… more

Date: June 1, 1980

Creator: Bauer, E.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Alkali-metal Rankine topping-cycle system design and development

The alkali metal vapor topping cycle with a steam cycle offers the potential of achieving a higher cycle efficiency than the steam cycle alone. An efficiency of about 50% is predicted for a cycle which employs either potassium or cesium with a vapor temperature at 1540/sup 0/F (837/sup 0/C) at the turbine inlet in a binary cycle where the metal vapor cycle is superimposed on a conventional steam cycle. A considerable amount of design and development work has been done by the Oak Ridge National … more

Date: January 1, 1982

Creator: Holcomb, R.S.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Large scale calculations of the structure and dynamics of dense matter

The physics of matter at high density has been found to be strongly influenced by transient quasi-molecular phenomena, the distribution of electron charge density among several nearby atoms. Calculations performed using the self-consistent field molecular dynamics approximation, a synthesis of techniques derived from quantum chemistry and molecular dynamics, have shown that such effects can result in more than a 30% increase in the diffusion coefficient of helium at 1 g/cc. The effect of finite… more

Date: January 1, 1989

Creator: Younger, S.M.

Item Type: Article

Partner: UNT Libraries Government Documents Department