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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 199 records · Page 11
All sourcesNASA NTRSDOE OSTI
NASA NTRS1986

Space Transportation Booster Engine (STBE) configuration study

The overall objective of this Space Transportation Booster Engine (STBE) study is to identify candidate engine configurations which enhance vehicle performance and provide operational flexibility at low cost. The specific objectives are as follows: (1) to identify and evaluate candidate LOX/HC engine configurations for the Advanced Space Transportation System for an early 1995 IOC and a late 2000 IOC; (2) to select one optimum engine for each time period; 3) to prepare a conceptual design for each configuration; (4) to develop a technology plan for the 2000 IOC engine; and, (5) to prepare preliminary programmatic planning and analysis for the 1995 IOC engine.

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NASA NTRS1987

Microgravity fluid management in two-phase thermal systems

Initial studies have indicated that in comparison to an all liquid single phase system, a two-phase liquid/vapor thermal control system requires significantly lower pumping power, demonstrates more isothermal control characteristics, and allows greater operational flexibility in heat load placement. As a function of JSC's Work Package responsibility for thermal management of space station equipment external to the pressurized modules, prototype development programs were initiated on the Two-Phase Thermal Bus System (TBS) and the Space Erectable Radiator System (SERS). JSC currently has several programs underway to enhance the understanding of two-phase fluid flow characteristics. The objective of one of these programs (sponsored by the Microgravity Science and Applications Division at NASA-Headquarters) is to design, fabricate, and fly a two-phase flow regime mapping experiment in the Shuttle vehicle mid-deck. Another program, sponsored by OAST, involves the testing of a two-phase thermal transport loop aboard the KC-135 reduced gravity aircraft to identify system implications of pressure drop variation as a function of the flow quality and flow regime present in a representative thermal system.

Parish, Richard C.↗
NASA NTRS1986

Orbit-on-demand vehicle propelled by air-turborocket/ramjet engines

A preliminary design study has been completed for a fully reusable, single-stage-to-orbit transatmospheric vehicle. The specified mission capability was to lift a 20,000 lb payload to low earth orbit. A ground accelerator-assisted horizontal take-off was chosen to increase operational flexibility. The multi-mode propulsion system included the use of air-turborocket, ramjet, scramjet and rocket engines. Weight and performance estimates were obtained for the vehicle. A computer package was developed to perform aerothermodynamic analyses of the propulsion modes throughout the flight environment from take-off to low earth orbit. Results are presented for a semi-optimized trajectory. The analysis indicates that a vehicle of this type has great potential for providing low cost, flexible access to space.

Hartung, L.↗
NASA NTRS1987

Science on Space Station

Plans for space science activities on the International Space Station are reviewed from a NASA perspective. The present Station reference configuration is based on a dual-keel core unit (one habitation module and three laboratory modules supplied by NASA, ESA, and Japan) and provides for five attached systems (with up to four payloads each to be exposed to space) and several free-flying platforms (both polar orbiters and coorbiters). Particular attention is given to the space science aspects of the primary Station objectives defined by NASA (servicing and repair, platforms, pressurized modules, and attached payloads). Also discussed are the work of the Task Force on Scientific Uses of Space Station, the need for operational flexibility, the value of a continuous manned presence for experimental science, and the skills needed from the Station crew.

Black, David C.↗
NASA NTRS1988

Shuttle performance enhancement using an uprated OMS engine

The NASA Space Shuttle's Orbital Maneuvering Engine (OME) has been investigated as the basis for an enhancement of Shuttle operational flexibility. The Johnson Space Center has given attention to an upgrading of the OME through the use of a gas generator-driven turbopump to raise engine specific impulse. Hardware tests have demonstrated the projected performance gains, which will yield an enhanced, intact ascent-abort capability, as well an an improved on-orbit payload and altitude capability. Attention is given to the application of these capabilities to the Hubble Space Telescope's deployment.

Mallini, Charles J.↗
NASA NTRS1988

Expendable launch vehicle transportation for the Space Station

ELVs are presently evaluated as major components of the NASA Space Station's logistics transportation system, augmenting the cargo capacity of the Space Shuttle in support of Station productivity and operational flexibility. The ELVs in question are the Delta II, Atlas II, Titan III, Titan IV, Shuttle-C (unmanned cargo development), European Ariane 5, and Japanese H-II, as well as smaller launch vehicles and OTVs. Early definition of ELV program impacts will preclude the potentially excessive costs of future Space Station modifications.

Corban, Robert R.↗
NASA NTRS1988

Mixed fleet assessment for on-orbit consumables resupply

Significant increases in the cost effectiveness and operational flexibility of in-space systems can be realized when the capability to replenish consumable fluids and propellants is incorporated into the designs of spacecraft, satellites, and orbiting platforms and laboratories. Reusable tankers are currently being designed for transporting fluids to space. A number of options exist for transporting the fluids and propellants to the space-based user systems. The fluids can be transported to space either in the Shuttle cargo bay or using Expendable Launch Vehicles (ELVs). Resupply can thus be accomplished either from the Shuttle bay, or the tanker can be removed from an ELV and attached to a carrier such as the Orbital Maneuvering Vehicle (OMV) or Orbital Transfer Vehicle (OTV) for transport to the user to be serviced. A third option involves locating the tanker at the Space Station or an unmanned platform as a quasi-permanent servicing facility which returns to the ground for recycling once its tanks have been depleted. This paper documents the impacts of a mixed fleet approach to consumables logistics to orbit. Both storable fluids and propellants, and superfluid helium, are considered. Current modular tanker designs for monopropellants, bipropellants and water for Space Station propulsion are discussed. Trade-offs in superfluid helium tanker sizes, shapes to fit the range of ELVs currently available, and boil-off losses associated with longer-term (greater than 6 months) space-basing, are addressed.

Eberhardt, Ralph N.↗
NASA NTRS1989

Advanced Recovery Systems for Advanced Launch Vehicles (ARS) phase 1 study results

The paper documents the work completed during the Advanced Recovery Systems for Advanced Launch Vehicles phase 1 study. Particular attention is given to the definition of the design of a single recovery system for the most likely near-term payload, a propulsion/avionic module (P/AM). A P/AM recovery system for phase 2 demonstration was designed which offers low cost, extremely low weight, good performance, potential for pinpoint loading, and operational flexibility.

Wailes, William K.↗
NASA NTRS1989

Advanced space recovery systems

The design evolution of a space recovery system designed by a NASA-contracted study is described, with particular attention given to the design of a recovery system for a propulsion/avionics module (P/AM), which weighs 60,000 lb at the recovery initiation and achieves subsonic terminal descent at or above 50,000 ft msl. The components of the recovery system concept are described together with the operational sequences of the recovery. The recovery system concept offers low cost, low weight, good performance, a potential for pinpoint landing, and an operational flexibility.

Wailes, William K.↗
NASA NTRS1989

Orbital Fluid Resupply Assessment

Orbital fluid resupply can significantly increase the cost-effectiveness and operational flexibility of spacecraft, satellites, and orbiting platforms and observatories. Reusable tankers are currently being designed for transporting fluids to space. A number of options exist for transporting the fluids and propellant to the space-based user systems. The fluids can be transported to space either in the Shuttle cargo bay or using expendable launch vehicles (ELVs). Resupply can thus be accomplished either from the Shuttle bay, or the tanker can be removed from the Shuttle bay or launched on an ELV and attached to a carrier such as the Orbital Maneuvering Vehicle (OMV) or Orbital Transfer Vehicle (OTV) for transport to the user to be serviced. A third option involves locating the tanker at the space station or an unmanned platform as a quasi-permanent servicing facility or depot which returns to the ground for recycling once its tanks are depleted. Current modular tanker designs for monopropellants, bipropellants, and water for space station propulsion are discussed. Superfluid helium tankers are addressed, including trade-offs in tanker sizes, shapes to fit the range of ELVs currently available, and boil-off losses associated with longer-term (greater than 6-month) space-basing. It is concluded that the mixed fleet approach to on-orbit consumables resupply offers significant advantages to the overall logistics requirements.

Eberhardt, Ralph N.↗
NASA NTRS1991

Resource envelope concepts for mission planning

Seven proposed methods for creating resource envelopes for Space Station Freedom mission planning are detailed. Four reference science activity models are used to illustrate the effect of adding operational flexibility to mission timelines. For each method, a brief explanation is given along with graphs to illustrate the application of the envelopes to the power and crew resources. The benefits and costs of each method are analyzed in terms of resource utilization. In addition to the effect on individual activities, resource envelopes are analyzed at the experiment level.

Ibrahim, K. Y.↗
NASA NTRS1990

The evolution of the Space Shuttle

As the mission manifest develops in response to the needs of the users, new capabilities are being developed for the Shuttle. Other changes are being introduced in order to provide Assured Shuttle Availability (ASA), that is, safe efficient flight operations into the 21st century. These changes will provide simpler turnaround processing procedures, enhanced subsystem reliability, a reduction in critical failure modes, and enhanced operational flexibility.

Cohen, Aaron↗
NASA NTRS1991

V/STOL gets a lift

The concept of a supersonic STOVL that could offer enhanced mission capability, survivability, operational flexibility, and utility over conventional aircraft is presented. Emphasis is currently on design studies, CFD work, small- and large-scale wind tunnel tests, simulation activities, flight experiments, and ground environment experiments. Propulsion system technology centers about the adaptation of existing or off-the-shelf engines. Concepts under study include separate flow in hover, gas-driven lift fan, and shaft-driven lift fan. NASA is examining generic valve and ducting configurations with airflow at ambient temperature and at temperatures up to 1000 F to gather pressure loss and heat transfer data. Advanced civil rotorcraft technologies examined include high-efficiency/dual-mode components such as torque converters; lightweight, quiet transmissions; and variable geometry power turbines; along with dual-function or convertible engines.

Biesiadny, Tom↗
NASA NTRS1992

SP-100 reactor with Brayton conversion for lunar surface applications

Examined here is the potential for integrating Brayton-cycle power conversion with the SP-100 reactor for lunar surface power system applications. Two designs were characterized and modeled. The first design integrates a 100-kWe SP-100 Brayton power system with a lunar lander. This system is intended to meet early lunar mission power needs while minimizing on-site installation requirements. Man-rated radiation protection is provided by an integral multilayer, cylindrical lithium hydride/tungsten (LiH/W) shield encircling the reactor vessel. Design emphasis is on ease of deployment, safety, and reliability, while utilizing relatively near-term technology. The second design combines Brayton conversion with the SP-100 reactor in a erectable 550-kWe powerplant concept intended to satisfy later-phase lunar base power requirements. This system capitalizes on experience gained from operating the initial 100-kWe module and incorporates some technology improvements. For this system, the reactor is emplaced in a lunar regolith excavation to provide man-rated shielding, and the Brayton engines and radiators are mounted on the lunar surface and extend radially from the central reactor. Design emphasis is on performance, safety, long life, and operational flexibility.

Mason, Lee S.↗
NASA NTRS1992

Synerjet propulsion and the trimarket opportunity - Orbital, transglobal and lunar transportation services with one vehicle type

A proposed aerospace transporter for performing earth-to-orbit/return missions as well as transatmospheric and in-space high-energy missions is argued to be an effective and feasible alternative for development. The vehicles are based on the exploitation of 'synerjet' technologies that use airbreathing/rocket combined-cycle propulsion. The vehicle is shown to be capable of terrestrial-service intercontinental transglobal flight in an 'orbital cruise' mode as well as round trips from low orbits to high orbits and to the moon. The operational flexibility is linked to the development of synerjet propulsion, so directions are proposed for technology development and validation efforts. The development of the NASP X-30 by NASA is shown to be an important initial contribution to the R&D in this direction.

Escher, William J. D.↗
NASA NTRS1989

Space Transportation Booster Engine Configuration Study. Volume 3: Program Cost estimates and work breakdown structure and WBS dictionary

The objective of the Space Transportation Booster Engine Configuration Study is to contribute to the ALS development effort by providing highly reliable, low cost booster engine concepts for both expendable and reusable rocket engines. The objectives of the Space Transportation Booster Engine (STBE) Configuration Study were: (1) to identify engine development configurations which enhance vehicle performance and provide operational flexibility at low cost; and (2) to explore innovative approaches to the follow-on Full-Scale Development (FSD) phase for the STBE.

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NASA NTRS1989

Space transportation booster engine configuration study. Volume 2: Design definition document and environmental analysis

The objective of the Space Transportation Booster Engine (STBE) Configuration Study is to contribute to the Advanced Launch System (ALS) development effort by providing highly reliable, low cost booster engine concepts for both expendable and reusable rocket engines. The objectives of the space Transportation Booster Engine (STBE) Configuration Study were: (1) to identify engine configurations which enhance vehicle performance and provide operational flexibility at low cost, and (2) to explore innovative approaches to the follow-on Full-Scale Development (FSD) phase for the STBE.

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