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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 1,621 records · Page 90
All sourcesNASA NTRSDOE OSTI
NASA NTRS1975

Analysis of operational requirements for medium density air transportation, volume 2

The medium density air travel market is examined and defined in terms of numbers of people transported per route per day and frequency of service. The operational characteristics for aircraft to serve this market are determined and a basepoint aircraft is designed from which tradeoff studies and parametric variations can be conducted. The impact of the operational characteristics on the air travel system is evaluated along with the economic viability of the study aircraft. Research and technology programs for future study consideration are identified.

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NASA NTRS1975

Analysis of operational requirements for medium density air transportation. Volume 1: Summary

The medium density air travel market was studied to determine the aircraft design and operational requirements. The impact of operational characteristics on the air travel system and the economic viability of the study aircraft were also evaluated. Medium density is defined in terms of numbers of people transported (20 to 500 passengers per day on round trip routes), and frequency of service ( a minumium of two and maximum of eight round trips per day) for 10 regional carriers. The operational characteristics of aircraft best suited to serve the medium density air transportation market are determined and a basepoint aircraft is designed from which tradeoff studies and parametric variations could be conducted. The impact of selected aircraft on the medium density market, economics, and operations is ascertained. Research and technology objectives for future programs in medium density air transportation are identified and ranked.

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NASA NTRS1974

Environmental microbiology as related to planetary quarantine

Continued experimental work related to dry heat resistance of microorganisms. One phase of this research has been concerned with the viability and dry heat resistance of indigenous microflora associated with small soil particles. The second part of this report is an analysis of the present status of dry heat sterilization. An attempt is made to integrate results for both laboratory grown spores and spores in soil.

Pflug, I. J.↗
NASA NTRS1975

Actuation and system design and evaluation OMS engine shutoff valve, Volume 1

A technology program was conducted to identify and verify the optimum valve and actuation system concept for the Space Shuttle Orbit Maneuvering System engine. Of major importance to the valve and actuation system selection was the ten-year, 100-mission, 10,000-cycle life requirement, while maintaining high reliability, low leakage, and low weight. Valve and actuation system concepts were comparatively evaluated against past valve failure reports and potential failure modes due to the shuttle mission profile to aid in the selection of the most optimum concept for design, manufacture and verification testing. Two valve concepts were considered during the preliminary design stage; i.e., the moving seat and lifting ball. Two actuation systems were manufactured and tested. Test results demonstrate the viability of a lifting ball concept as well as the applicability of an ac motor actuation system to best meet the requirements of the shuttle mission.

Dunn, V. B.↗
NASA NTRS1975

Market study: Biological isolation garment

The biological isolation garment was originally designed for Apollo astronauts to wear upon their return to earth from the moon to avoid the possibility of their contaminating the environment. The concept has been adapted for medical use to protect certain patients from environmental contamination and the risk of infection. The nature and size of the anticipated market are examined with certain findings and conclusions relative to clinical acceptability and potential commercial viability of the biological isolation garment.

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NASA NTRS1975

The polarimeter and the multispectral radiometer as remote probes of aerosols

Attempts made to establish the viability of the polarimeter as a ground based remote probe of atmospheric aerosols under varying meteorological conditions are reported. Extension radiometer data are also given and a comparison was made with polarimeter data to determine if one could complement/supplement the other. The analyses show that the two instruments are complementary devices and any information obtained from one will greatly facilitate the analysis of the other. Detailed results are given in graphical form.

Kuriyan, J. G.↗
NASA NTRS1974

A spacecraft integrated power/attitude control system

A study to determine the viability and application of a system capable of performing the dual function of power storage/generation and attitude control has been conducted. Results from the study indicate that an integrated power/attitude control system (IPACS) can satisfy future mission requirements while providing significant savings in weight, volume, and cost over conventional systems. A failure-mode configuration of an IPACS was applied to a shuttle-launched RAM free-flyer and simulated using make-do hardware linked to a hybrid computer. Data from the simulation runs indicate that control interactions resulting from heavy power demands have minimal effect on system control effectiveness. The system was shown to be capable of meeting the stringent pointing requirements of 1 arc-second while operating under the influence of an orbital disturbance environment and during periods of momentum variations imposed by energy transfer requirements.

Keckler, C. R.↗
NASA NTRS1974

Determination of optical parameters of atmospheric particulates from ground-based polarimeter measurements

This paper describes the theoretical analysis that is required to infer, from polarimeter measurements of skylight, the size distribution, refractive index and abundance of particulates in the atmosphere. To illustrate the viability of the method, some data obtained at UCLA is analyzed and the atmospheric parameters are derived. The explicit demonstration of the redundancy in the description of aerosol distributions suggests that radiation field measurements will not uniquely determine the modal radius of the size distribution. In spite of this nonuniqueness information useful to heat budget calculations can be derived.

Kuriyan, J. G.↗
NASA NTRS1974

Remote sensor evaluation model

A format is presented that enables the specification of a sensor system configuration, given a set of knowledge requirements to be satisfied by an earth observation satellite. This format, in a modified form, may also be used to determine whether or not a knowledge requirement can be satisfied by existing sensors, and to indicate the need for developing new sensors. It can be applied to large sets of knowledge requirements, so that versatile, multipurpose earth observation sensor systems can be developed. Implementation of the model to a combination of Nimbus G&H and ERTS E&F missions is shown as a test of its viability. The findings are extensively tabulated, and they tend to support the method.

Kerne, B.↗
NASA NTRS1975

Interagency Workshop on Lighter than Air Vehicles, Monterey, Calif., September 9-13, 1974, Proceedings

Papers are presented which review modern lighter-than-air (LTA) airship design concepts and LTA structures and materials technology, as well as perform economic and market analyses for assessment of the viability of future LTA development programs. Potential applications of LTA vehicles are examined. Some of the topics covered include preliminary estimates of operating costs for LTA transports, an economic comparison of three heavy lift airborn systems, boundary layer control for airships, computer aided flexible envelope designs, state-of-the-art of metalclad airships, aspects of hybrid-Zeppelins, the LTA vehicle as a total cargo system, unmanned powered balloons, and a practical concept for powered or tethered weight-lifting LTA vehicles. Individual items are announced in this issue.

Vittek, J. F., Jr.↗
NASA NTRS1975

Computation of separated transonic turbulent flows

The two-dimensional Reynolds-averaged compressible Navier-Stokes equations are solved using MacCormack's second-order-accurate explicit finite difference method to simulate the separated transonic turbulent flow field over an airfoil. Four different algebraic eddy viscosity models are tested for viability to achieve turbulence closure for the class of flows considered. These models range from an unmodified boundary-layer mixing-length model to a relaxation model incorporating special considerations for the separation bubble region. Results of this study indicate the necessity for special attention to the separated flow region and suggest limits of applicability of algebraic turbulence models to these separated flow fields.

Deiwert, G. S.↗
NASA NTRS1975

Space processing of crystals for opto-electronic devices: The case for solution growth

The results obtained during a six month program aimed at determining the viability of space processing in the 1980's of dielectric-elastic-magnetic single crystals were described. The results of this program included: identification of some important emerging technologies dependent on dielectric-elastic-magnetic crystals, identification of the impact of intrinsic properties and defects in the single crystals on system performance, determination of a sensible common basis for the many crystals of this class, and identification of the benefits of micro-gravity and some initial experimental evidence that these benefits can be realized in space. It is concluded that advanced computers and optical communications are at a development stage for high demand of dielectric-elastic-magnetic single crystals in the mid-1980's. Their high unit cost and promise for significantly increased perfection by growth in space justified pursuit of space processing.

Hayden, S. C.↗
NASA NTRS1975

The aerospace developments concept

The viability of using airships for the transport of natural gas, and the initial design of such a system, the airship and its associated subsystems together with a continuing economic analysis of the project were investigated. Investigations, on a funded basis, were also carried out into the application of the airship for A.S.W. and A.E.W. uses, and a further investigation into the transport of mineral concentrates for an Australasian mining concern was completed.

Wood, J. E. R.↗
NASA NTRS1975

Bioluminescence for determining energy state of plants

Bioluminescence produced by the luciferin-luciferase system is a very sensitive assay for ATP content in extracts of plant materials. The ATP test for seed and pollen viability and vigor is presented, along with prediction of high growth potential and productivity in new crosses and selections of breeding materials. ATP as an indicator for environmental quality, stresses, and metabolic regulation is also considered.

Ching, T. M.↗
NASA NTRS1976

Preliminary assessment of systems for deriving liquid and gaseous fuels from waste or grown organics

The overall feasibility of the chemical conversion of waste or grown organic matter to fuel is examined from the technical, economic, and social viewpoints. The energy contribution from a system that uses waste and grown organic feedstocks is estimated as 4 to 12 percent of our current energy consumption. Estimates of today's market prices for these fuels are included. Economic and social issues are as important as technology in determining the feasibility of such a proposal. An orderly program of development and demonstration is recommended to provide reliable data for an assessment of the viability of the proposal.

Graham, R. W.↗
NASA NTRS1976

Separation of granulocytes from whole blood by leukoadhesion, phase 1

Capillary glass tubes are investigated for the separation and retrieval of large quantities of viable granulocytes and monocytes from whole blood on a continuous basis from a single donor. This effort represented the feasibility demonstration of a three phase program for development of a capillary tube cell separation device. The activity included the analysis and parametric laboratory testing with subscale models required to design a prototype device. Capillary tubes 40 cm long with a nominal 0.030 cm internal diameter yielded the highest total process efficiency. Recovery efficiencies as high as 89% of the adhering cell population were obtained. Granulocyte phagocytosis of latex particles indicated approximately 90% viability. Monocytes recovered from the separation column retained their capability to stimulate human bone marrow colony growth, as demonstrated in an in vitro cell culture assay.

Source record↗
NASA NTRS1975

Northeast Utilities' participation in the Kaman/NASA wind power program

The role of Northeast Utilities in the Kaman/NASA large wind generator study is reviewed. The participation falls into four principal areas: (1) technical assistance; (2) economic analysis; (3) applications; and (4) institutional and legal. A model for the economic viability of wind power is presented.

Lotker, M.↗
NASA NTRS1976

Design, economic and system considerations of large wind-driven generators

The increased search for alternative energy sources has lead to renewed interest and studies of large wind-driven generators. This paper presents the results and considerations of such an investigation. The paper emphasizes the concept selection of wind-driven generators, system optimization, control system design, safety aspects, economic viability on electric utility systems and potential electric system interfacing problems.

Jorgensen, G. E.↗