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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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At least 379 records · Page 21
All sourcesNASA NTRSDOE OSTI
NASA NTRS1971

Preliminary design of a shuttle docking and cargo handling system

Work performed prior to concept selection, concept evaluation, and the preliminary design are summarized. The initial work included selection of the requirements and guidelines used to formulate concepts; analysis to determine detailed requirements for reach, velocity, torque, etc.; formulation of the alternative concepts; the evaluation and ranking of the concepts; and the selection of a concept. The man-in-the-loop simulation performed with a six degree of freedom moving base simulator and a three degree of freedom manipulator arm are described. The analysis and tradeoffs of those design parameters which are the key to the preliminary design are described. Estimates for a future development program are presented, including a schedule and manpower breakdown and cost estimate. The system design parameters, with a weight and power breakdown are summarized.

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NASA NTRS1972

Satellite broadcasting system study

The study to develop a system model and computer program representative of broadcasting satellite systems employing community-type receiving terminals is reported. The program provides a user-oriented tool for evaluating performance/cost tradeoffs, synthesizing minimum cost systems for a given set of system requirements, and performing sensitivity analyses to identify critical parameters and technology. The performance/ costing philosophy and what is meant by a minimum cost system is shown graphically. Topics discussed include: main line control program, ground segment model, space segment model, cost models and launch vehicle selection. Several examples of minimum cost systems resulting from the computer program are presented. A listing of the computer program is also included.

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NASA NTRS1972

Effects of radiation environment on reusable nuclear shuttle system

Parametric tradeoff analyses of a wide spectrum of alternate tank configurations to minimize both primary and secondary, direct and scattered radiation sources emanating from the NERVA are reported. The analytical approach utilizing point kernel techniques is described and detailed data are presented on the magnitude of neutron/gamma doses for different locations. Single-tank configurations utilizing smaller cone angles and end cap radii were found to minimize integral radiation levels, hence, stage shielding-weight penalties for shuttle missions. Hybrid configurations employing an upper tank with a reduced cone angle and end cap radius result in low integral payload doses primarily due to the increased separation distance caused by the elongation of the larger capacity upper tank. A preliminary radiation damage assessment is discussed of possible reusable nuclear shuttle materials, components, and subsystems, and the possible effects of the radiation environment on various phases of RNS mission operations.

Lane, A. G.↗
NASA NTRS1971

Information transfer satellite concept study. Volume 1: Summary

A wide range of information transfer demands were identified and analyzed. They were then combined into an appropriate set of requirements for satellite communication services. In this process the demands were ranked and combined into single and multipurpose satellite systems. A detailed analysis was performed on each satellite system to determine: total system cost, including both ground and space segments; sensitivities of the systems to various system tradeoffs; and forcing functions which control the system variations. A listing of candidate missions for detailed study is presented, along with a description of the conceptual system design and an identification of the technology developments required to bring these systems to fruition.

Bergin, P.↗
NASA NTRS1971

Information transfer satellite concept study. Volume 4: computer manual

The Satellite Telecommunications Analysis and Modeling Program (STAMP) provides the user with a flexible and comprehensive tool for the analysis of ITS system requirements. While obtaining minimum cost design points, the program enables the user to perform studies over a wide range of user requirements and parametric demands. The program utilizes a total system approach wherein the ground uplink and downlink, the spacecraft, and the launch vehicle are simultaneously synthesized. A steepest descent algorithm is employed to determine the minimum total system cost design subject to the fixed user requirements and imposed constraints. In the process of converging to the solution, the pertinent subsystem tradeoffs are resolved. This report documents STAMP through a technical analysis and a description of the principal techniques employed in the program.

Bergin, P.↗
NASA NTRS1972

Modular Space Station Phase B Extension Preliminary Systems Design Report. Volume VI: Trades and Analyses

This document contains trades and analyses conducted during the Modular Space Station Phase B System Definition. Requirements and concepts considered and the tradeoff analysis leading to the preferred concept are presented. Integrated analyses are presented for subsystems and thermal control. Specific trades and analyses are presented for water management, atmosphere control, energy storage, radiators, navigation, control moment gyros, and system maintenance. The analyses of manipulator concepts and requirements, and supplemental analyses of information management issues are summarized. Subsystem reliability analyses include a detailed discussion of the critical failure analysis.

Jones, A. L.↗
NASA NTRS1972

Antenna feeds and receivers

The results of 7 months of study, tradeoffs, test design, and fabrication are presented for an effort to modify three ground stations in support of the ATS-F program. As a result of tests on the existing feed system of the Rosman No. 2 85-foot antenna and on the transportable ground station (TGS) 40-foot antenna, it was determined that modifications of the existing phase-compensating rotary joints at Rosman are feasible. Other components must be completely replaced. In the TGS antenna feed system, it was found to be feasible to broadband the existing monopulse comparator by adding simple irises and posts; both spare and active comparators were modified. The TGS polarizers can be broadbanded by adjusting existing pins and adding two new pins. These modifications are also directly applicable to the Mojave 40-foot antenna. Detailed electrical and mechanical characteristics are presented for the new equipment, as well as installation plans to enable NASA and its contractors to determine the adequacy of the designs and to confirm that planned locations are both available and compatible with planned operational concepts.

Mccall, B.↗
NASA NTRS1972

Feasibility study of a pressure-fed engine for a water recoverable space shuttle booster. Volume 1: Executive summary

The activities leading to a tentative concept selection for a pressure-fed engine and propulsion support are outlined. Multiple engine concepts were evaluted through parallel engine major component and system analyses. Booster vehicle coordination, tradeoffs, and technology/development aspects are included. The concept selected for further evaluation has a regeneratively cooled combustion chamber and nozzle in conjuction with an impinging element injector. The propellants chosen are LOX/RP-1, and combustion stabilizing baffles are used to assure dynamic combustion stability.

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NASA NTRS1972

Space station ventilation study

A ventilation system design and selection method which is applicable to any manned vehicle were developed. The method was used to generate design options for the NASA 33-foot diameter space station, all of which meet the ventilation system design requirements. System characteristics such as weight, volume, and power were normalized to dollar costs for each option. Total system costs for the various options ranged from a worst case $8 million to a group of four which were all approximately $2 million. A system design was then chosen from the $2 million group and is presented in detail. A ventilation system layout was designed for the MSFC space station mockup which provided comfortable, efficient ventilation of the mockup. A conditioned air distribution system design for the 14-foot diameter modular space station, using the same techniques, is also presented. The tradeoff study resulted in the selection of a system which costs $1.9 million, as compared to the alternate configuration which would have cost $2.6 million.

Colombo, G. V.↗
NASA NTRS1971

Modular space station detailed preliminary design. Volume 1: Sections 1 through 4.4

Detailed configuration and subsystems preliminary design data are presented for the modular space station concept. Each module comprising the initial space station is described in terms of its external and internal configuration, its functional responsibilities to the initial cluster, and its orbital build up sequence. Descriptions of the subsequent build up to the growth space station are also presented. Analytical and design techniques, tradeoff considerations, and depth of design detail are discussed for each subsystem. The subsystems include the following: structural/mechanical; crew habitability and protection; experiment support; electrical power; environmental control/life support; guidance, navigation, and control; propulsion; communications; data management; and onboard checkout subsystems. The interfaces between the station and other major elements of the program are summarized. The rational for a zero-gravity station, in lieu of one with artificial-gravity capability, is also summarized.

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NASA NTRS1972

Analysis of requirements for GEOS-C laser cube-corner reflector panels

A mathematical analysis of the tradeoffs and requirements was performed to develop an improved array design which will give stronger returns at lower elevation angles and reduce pulse spread in the return. It was determined that a zenith angle of 75deg can be obtained with an array with an area of 0.28 sq m, if the array is shaped on the surface of a 45 deg cone whose axis is coincident to the satellite axis. The total weight of the truncated pyramid array with 270 cube corners is calculated to be not more than 50% greater than the GEOS 2 array, while the efficiency is increased 275%.

Minott, P. O.↗
NASA NTRS1972

The social function of technology assessment

The problem of preserving the uneasy balance between a dynamic society and the equilibrium of man-environment society is discussed. Four sets of activities involved in technology assessment are considered: (1) Technology forecasting is necessary to warn of future dangers and opportunities, for effective timing, and to identify tradeoffs and alternatives. But forecasting is also chancy at best. (2) Social indicators need to be developed for the characterization of social status and measurement of social progress, as well as a better understanding of social needs. (3) With respect to technology assessment, the conflict between profitable directions of innovations and socially desirable directions is described, and a systematic way is needed to determine in advance what is technologically feasible to meet social needs. (4) National goals with respect to scientific and technological developments are also required.

Huddle, F. P.↗
NASA NTRS1972

Design considerations for fiber composite structures

An overview of the design methodology for designing structural components from fiber composites is presented. In particular, the need for new conceptual structural designs for the future is discussed and the evolution of conceptual design is illustrated. Sources of design data, analysis and design procedures, and the basic components of structural fiber composites are cited and described. Examples of tradeoff studies and optimum designs are discussed and a simple structure is described in some detail.

Chamis, C. C.↗
NASA NTRS1970

Study of optimum propellant production facilities for launch of space shuttle vehicles

An integrated propellant manufacturing plant and distribution system located at Kennedy Space Center is studied. The initial planned propellant and pressurant production amounted to 160 tons/day (TPD) LH2, 10 TPD GH2, 800 TPD LO2, 400 TPD LN2, and 120 TPD GN2. This was based on a shuttle launch frequency of 104 per year. During the study, developments occurred which may lower cryogen requirements. A variety of plant and processing equipment sizes and costs are considered for redundancy and supply level considerations. Steam reforming is compared to partial oxidation as a means of generating hydrogen. Electric motors, steam turbines, and gas turbines are evaluated for driving compression equipment. Various sites on and off Government property are considered to determine tradeoffs between costs and problems directly associated with the site, product delivery and storage costs, raw material costs, and energy costs. Coproduction of other products such as deuterium, methanol, and ammonia are considered. Legal questions are discussed concerning a private company's liabilities and its rights to market commercial products under Government tax and cost shelters.

Laclair, L. M.↗
NASA NTRS1972

Solid propulsion advanced concepts

The feasibility and application of a solid propulsion powered spacecraft concept to implement high energy missions independent of multiplanetary swingby opportunities are assessed and recommendations offered for future work. An upper stage, solid propulsion launch vehicle augmentation system was selected as the baseline configuration in view of the established program goals of low cost and high reliability. Spacecraft and propulsion system data that characterize mission performance capabilities were generated to serve as the basis for subsequent tradeoff studies. A cost effectiveness model was used for the preliminary feasibility assessment to provide a meaningful comparative effectiveness measure of the various candidate designs. The results substantiated the feasibility of the powered spacecraft concept when used in conjunction with several intermediate-sized launch vehicles as well as the existence of energy margins by which to exploit the attainment of extended mission capabilities. Additionally, in growth option applications, the employment of advanced propulsion systems and alternate spacecraft approaches appear promising.

Nakamura, Y.↗