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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 505 records · Page 28
All sourcesNASA NTRSDOE OSTI
NASA NTRS1977

Solar array conceptual design for the Halley's Comet ion drive mission, phase 2

Conceptual design studies were performed directed toward a high power, ultralightweight solar array, compatible with the requirements for the Halley's Comet Ion Drive Mission. A planar, rollup array design concept capable of producing 120 kW at 1 AU and 6 kW at 4.5 AU, and a concentrator, rollup array design concept capable of producing 60 kW at 1 AU and 15.5 kW at 4.5 AU evolved. Both arrays make maximum use of thin film, lightweight technology. The Halley's Comet spacecraft and mission requirements developed from preliminary definition to a more finalized and mature design. As solar array requirements were updated, conceptual design iterations were necessary to keep pace with the rapidly changing program objectives and goals. The Halley's Comet Mission program status and design approaches were reviewed and more realistic power requirements at 4.5 AU for the ion engines were established at the 12 to 16 kW range. This higher power necessitated a change from the planar array design to a concentrator array design in order to remain within suitable cost and weight objectives.

Rayl, G. J.↗
NASA NTRS1994

Methodologies for processing plant material into acceptable food on a small scale

Based on the Controlled Environment Life Support System (CELSS) production of only four crops, wheat, white potatoes, soybeans, and sweet potatoes; a crew size of twelve; a daily planting/harvesting regimen; and zero-gravity conditions, estimates were made on the quantity of food that would need to be grown to provide adequate nutrition; and the corresponding amount of biomass that would result. Projections were made of the various types of products that could be made from these crops, the unit operations that would be involved, and what menu capability these products could provide. Equipment requirements to perform these unit operations were screened to identify commercially available units capable of operating (or being modified to operate) under CELSS/zero-gravity conditions. Concept designs were developed for those equipment needs for which no suitable units were commercially available. Prototypes of selected concept designs were constructed and tested on a laboratory scale, as were selected commercially available units. This report discusses the practical considerations taken into account in the various design alternatives, some of the many product/process factors that relate to equipment development, and automation alternatives. Recommendations are made on both general and specific areas in which it was felt additional investigation would benefit CELSS missions.

Parks, Thomas R.↗
NASA NTRS2005

Galium Electromagnetic (GEM) Thruster Concept and Design

We describe the design of a new type of two-stage pulsed electromagnetic accelerator, the gallium electromagnetic (GEM) thruster. A schematic illustration of the GEM thruster concept is given. In this concept, liquid gallium propellant is pumped into the first stage through a porous metal electrode using an electromagnetic pump. At a designated time, a pulsed discharge (approx. 10-50 J) is initiated in the first stage, ablating the liquid gallium from the porous electrode surface and ejecting a dense thermal gallium plasma into the second state. The presence of the gallium plasma in the second stage serves to trigger the high-energy (approx. 500 J), second-stage pulse which provides the primary electromagnetic (j x B) acceleration.

Polzin, Kurt A.↗
NASA NTRS2006

Gallium Electromagnetic (GEM) Thrustor Concept and Design

We describe the design of a new type of two-stage pulsed electromagnetic accelerator, the gallium electromagnetic (GEM) thruster. A schematic illustration of the GEM thruster concept is given in Fig. 1. In this concept, liquid gallium propellant is pumped into the first stage through a porous metal electrode using an electromagneticpump[l]. At a designated time, a pulsed discharge (approx.10-50 J) is initiated in the first stage, ablating the liquid gallium from the porous electrode surface and ejecting a dense thermal gallium plasma into the second state. The presence of the gallium plasma in the second stage serves to trigger the high-energy (approx.500 I), send-stage puke which provides the primary electromagnetic (j x B) acceleration.

Polzin, Kurt A.↗
NASA NTRSDate not supplied

Advanced Concepts Office

Capabilities Overview: About the Advanced Concepts Office - ACO informs decision makers by providing rapid, Pre-Phase A concept designs and studies for space systems - Multi-disciplinary team representing all engineering disciplines - Work Pre-Phase A concept designs and studies - Analysis of alternatives - Quantitative technology assessments - Systems analysis and optimization

Eric C. Sholes↗
NASA NTRS1979

Preliminary studies of a turbofan engine and fuel system for use with liquid hydrogen

A study of design concepts for the application of the properties of LH2 in a turbofan engine for air transport is presented. The study showed the benefits from the reduction of aircraft direct operating cost. Design concepts for the engine fuel delivery and control system, including the engine high pressure fuel pump, were developed and general concept feasibility was demonstrated. Recommendations were made for the advanced development required for design application for both the engine, the fuel delivery, and the control system.

Baerst, C. F.↗
NASA NTRS1979

Wide field/planetary camera optics study

Design feasibility of the baseline optical design concept was established for the wide field/planetary camera (WF/PC) and will be used with the space telescope (ST) to obtain high angular resolution astronomical information over a wide field. The design concept employs internal optics to relay the ST image to a CCD detector system. Optical design performance predictions, sensitivity and tolerance analyses, manufacturability of the optical components, and acceptance testing of the two mirror Cassegrain relays are discussed.

Source record↗
NASA NTRS1990

Hybrid propulsion technology program

Technology was identified which will enable application of hybrid propulsion to manned and unmanned space launch vehicles. Two design concepts are proposed. The first is a hybrid propulsion system using the classical method of regression (classical hybrid) resulting from the flow of oxidizer across a fuel grain surface. The second system uses a self-sustaining gas generator (gas generator hybrid) to produce a fuel rich exhaust that was mixed with oxidizer in a separate combustor. Both systems offer cost and reliability improvement over the existing solid rocket booster and proposed liquid boosters. The designs were evaluated using life cycle cost and reliability. The program consisted of: (1) identification and evaluation of candidate oxidizers and fuels; (2) preliminary evaluation of booster design concepts; (3) preparation of a detailed point design including life cycle costs and reliability analyses; (4) identification of those hybrid specific technologies needing improvement; and (5) preperation of a technology acquisition plan and large scale demonstration plan.

Source record↗
NASA NTRS2016

A High-Heritage Blunt-Body Entry, Descent, and Landing Concept for Human Mars Exploration

Human-scale landers require the delivery of much heavier payloads to the surface of Mars than is possible with entry, descent, and landing (EDL) approaches used to date. A conceptual design was developed for a 10 m diameter crewed Mars lander with an entry mass of approx.75 t that could deliver approx.28 t of useful landed mass (ULM) to a zero Mars areoid, or lower, elevation. The EDL design centers upon use of a high ballistic coefficient blunt-body entry vehicle and throttled supersonic retro-propulsion (SRP). The design concept includes a 26 t Mars Ascent Vehicle (MAV) that could support a crew of 2 for approx.24 days, a crew of 3 for approx.16 days, or a crew of 4 for approx.12 days. The MAV concept is for a fully-fueled single-stage vehicle that utilizes a single pump-fed 250 kN engine using Mono-Methyl Hydrazine (MMH) and Mixed Oxides of Nitrogen (MON-25) propellants that would deliver the crew to a low Mars orbit (LMO) at the end of the surface mission. The MAV concept could potentially provide abort-to-orbit capability during much of the EDL profile in response to fault conditions and could accommodate return to orbit for cases where the MAV had no access to other Mars surface infrastructure. The design concept for the descent stage utilizes six 250 kN MMH/MON-25 engines that would have very high commonality with the MAV engine. Analysis indicates that the MAV would require approx.20 t of propellant (including residuals) and the descent stage would require approx.21 t of propellant. The addition of a 12 m diameter supersonic inflatable aerodynamic decelerator (SIAD), based on a proven flight design, was studied as an optional method to improve the ULM fraction, reducing the required descent propellant by approx.4 t.

Mars lander↗
NASA NTRS2016

A High-Heritage Blunt-Body Entry, Descent, and Landing Concept for Human Mars Exploration

Human-scale landers require the delivery of much heavier payloads to the surface of Mars than is possible with entry, descent, and landing (EDL) approaches used to date. A conceptual design was developed for a 10 m diameter crewed Mars lander with an entry mass of approx. 75 t that could deliver approx. 28 t of useful landed mass (ULM) to a zero Mars areoid, or lower, elevation. The EDL design centers upon use of a high ballistic coefficient blunt-body entry vehicle and throttled supersonic retro-propulsion (SRP). The design concept includes a 26 t Mars Ascent Vehicle (MAV) that could support a crew of 2 for approx. 24 days, a crew of 3 for approx.16 days, or a crew of 4 for approx.12 days. The MAV concept is for a fully-fueled single-stage vehicle that utilizes a single pump-fed 250 kN engine using Mono-Methyl Hydrazine (MMH) and Mixed Oxides of Nitrogen (MON-25) propellants that would deliver the crew to a low Mars orbit (LMO) at the end of the surface mission. The MAV concept could potentially provide abort-to-orbit capability during much of the EDL profile in response to fault conditions and could accommodate return to orbit for cases where the MAV had no access to other Mars surface infrastructure. The design concept for the descent stage utilizes six 250 kN MMH/MON-25 engines that would have very high commonality with the MAV engine. Analysis indicates that the MAV would require approx. 20 t of propellant (including residuals) and the descent stage would require approx. 21 t of propellant. The addition of a 12 m diameter supersonic inflatable aerodynamic decelerator (SIAD), based on a proven flight design, was studied as an optional method to improve the ULM fraction, reducing the required descent propellant by approx.4 t.

Mars lander↗
DOE OSTI2026

Physics basis for the reference flat-top plasma scenario in the ST–E1 fusion power plant

As part of the U.S. Department of Energy’s Milestone-Based Fusion Energy Development Program, Tokamak Energy has completed the pre-concept design of the ST–E1 fusion power plant. ST–E1 is envisaged to operate in two phases: a pilot plant phase, targeting sustained net power production of 300 - 500 MWe for a duration >1 hr, followed by a commercial power plant phase targeting steady-state operations and a normalised overnight capital cost of ⩽12 000 $\$$/kWe. The design process adopted was highly iterative, integrating all major plant systems and progressing in a phased fidelity approach. At the pre-conceptual stage, the emphasis has been on exploring the design space, identifying the main system-level trade-offs, and making the key decisions that define the overall plant concept, rather than optimising a single operating point. This paper, part of a focused collection detailing the ST–E1 pre-concept design, addresses the development of a series of reference flat-top plasma operating points for the pilot plant phase. A modelling workflow was established to develop and assess candidate plasma design points and explore key dependencies. The workflow includes integrated core plasma modelling, magnetohydrodynamic (MHD) stability assessment, equilibrium generation, scrape-off-layer and exhaust modelling, heating & current drive design and optimisation, and turbulent transport modelling. Using this framework, the impact of several key parameters on the flat-top operating space was investigated, including the density limit, core radiation fraction and divertor power loading, level of external heating and curent drive power and assumed pedestal characteristics. The MHD stability, controllability and micro-stability characteristics of these plasmas were also analysed. These investigations informed the definition of a set of fully non-inductive, flat-top reference operating points that satisfy the high-level ST–E1 mission, including a low and high density case, a case that is stable to resistive wall modes and a case with reduced divertor power loading.

ST–E1↗
NASA NTRS1973

Structural considerations in design of lightweight glass-fiber composite pressure vessels

The design concepts used for metal-lined glass-fiber composite pressure vessels are described, comparing the structural characteristics of the composite designs with each other and with homogeneous metal pressure vessels. Specific design techniques and available design data are identified. The discussion centers around two distinctly different design concepts, which provide the basis for defining metal lined composite vessels as either (1) thin-metal lined, or (2) glass fiber reinforced (GFR). Both concepts are described and associated development problems are identified and discussed. Relevant fabrication and testing experience from a series of NASA-Lewis Research Center development efforts is presented.

Faddoul, J. R.↗
NASA NTRS1990

Enroute flight planning: The design of cooperative planning systems

Design concepts and principles to guide in the building of cooperative problem solving systems are being developed and evaluated. In particular, the design of cooperative systems for enroute flight planning is being studied. The investigation involves a three stage process, modeling human performance in existing environments, building cognitive artifacts, and studying the performance of people working in collaboration with these artifacts. The most significant design concepts and principles identified thus far are the principle focus.

Smith, Philip J.↗
NASA NTRS1991

Goertler instability and hypersonic quiet nozzle design

A concept for nozzle design which incorporates slow expansion rates and a radial flow region is developed for use on a hypersonic (Mach 6) nozzle. It is shown that the boundary-layer suction slot upstream of the nozzle throat is necessary to remove upstream turbulent boundary layers and to initialize a new laminar boundary layer on the downstream nozzle wall. In effect, the laminar boundary-layer flow can be extended more effectively farther downstream by a slow expansion contour based on the present design concept than by a rapid expansion contour used in previous pilot quiet nozzles.

Chen, Fang-Jenq↗
NASA NTRS2004

Advanced EVA Capabilities: A Study for NASA's Revolutionary Aerospace Systems Concept Program

This report documents the results of a study carried out as part of NASA s Revolutionary Aerospace Systems Concepts Program examining the future technology needs of extravehicular activities (EVAs). The intent of this study is to produce a comprehensive report that identifies various design concepts for human-related advanced EVA systems necessary to achieve the goals of supporting future space exploration and development customers in free space and on planetary surfaces for space missions in the post-2020 timeframe. The design concepts studied and evaluated are not limited to anthropomorphic space suits, but include a wide range of human-enhancing EVA technologies as well as consideration of coordination and integration with advanced robotics. The goal of the study effort is to establish a baseline technology "road map" that identifies and describes an investment and technical development strategy, including recommendations that will lead to future enhanced synergistic human/robot EVA operations. The eventual use of this study effort is to focus evolving performance capabilities of various EVA system elements toward the goal of providing high performance human operational capabilities for a multitude of future space applications and destinations. The data collected for this study indicate a rich and diverse history of systems that have been developed to perform a variety of EVA tasks, indicating what is possible. However, the data gathered for this study also indicate a paucity of new concepts and technologies for advanced EVA missions - at least any that researchers are willing to discuss in this type of forum.

Hoffman, Stephen J.↗
NASA NTRS1974

Evaluation of a metal shear web selectively reinforced with filamentary composites for space shuttle application

A final program summary is reported for test and evaluation activities that were conducted for space shuttle web selection. Large scale advanced composite shear web components were tested and analyzed to evaluate application of advanced composite shear web construction to a space shuttle orbiter thrust structure. The shear web design concept consisted of a titanium-clad + or - 45 deg boron/epoxy web laminate stiffened with vertical boron-epoxy reinforced aluminum stiffeners and logitudinal aluminum stiffening. The design concept was evaluated to be efficient and practical for the application that was studied. Because of the effects of buckling deflections, a requirement is identified for shear buckling resistant design to maximize the efficiency of highly-loaded advanced composite shear webs.

Laakso, J. H.↗
NASA NTRS2004

Cryogenic Composite Tank Design for Next Generation Launch Technology

The structural performance of liquid hydrogen tanks made from composites is investigated. A computational method that judiciously combines structural analysis, composite mechanics, progressive fracture algorithm to evaluate damage tolerance, durability, and fatigue and fracture is described. A tank design concept is introduced and evaluated. The composite tank is internally stiffened by incorporating additional stacks of laminates along its length to alternate rows of finite elements. The robustness of the proposed design concept is assessed by damage progression analysis. Damage initiates i the composite at an internal pressure that is nearly two times the design pressure. From the point of damage initiation, the designed tank can tolerate an increase in internal pressure that is nearly three and a half times the design pressure. Low cycle fatigue analysis is also performed to determine the effect of pressurization and de-pressurization on the structural integrity of the tank. Results show that the tank can sustain at least a 100 cycles before any failure take place.

Abumen, Galib H.↗