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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 793 records · Page 44
All sourcesNASA NTRSDOE OSTI
NASA NTRS1986

Space station propulsion technology

The progress on the Space Station Propulsion Technology Program is described. The objectives are to provide a demonstration of hydrogen/oxygen propulsion technology readiness for the Initial Operating Capability (IOC) space station application, specifically gaseous hydrogen/oxygen and warm hydrogen thruster concepts, and to establish a means for evolving from the IOC space station propulsion to that required to support and interface with advanced station functions. The evaluation of concepts was completed. The accumulator module of the test bed was completed and, with the microprocessor controller, delivered to NASA-MSFC. An oxygen/hydrogen thruster was modified for use with the test bed and successfully tested at mixture ratios from 4:1 to 8:1.

Briley, G. L.↗
NASA NTRS1985

Design of a regenerative fuel cell system for Space Station

The NASA Space Station will employ alkaline regenerative fuel cells (RFCs) as its sole electrochemical energy storage system, in virtue of demonstrated technology readiness and a high degree of system-level design flexibility. NASA Johnson and NASA Lewis are currently engaged in the development of a 10-kW alkaline engineering model system, for 1987 delivery, which will encompass a fully autonomous 120-V system with 55 percent overall electrical efficiency and a 20,000-hr service life.

Hoberecht, M. A.↗
NASA NTRS1986

Performance and endurance tests of a multipropellant resistojet for space station auxiliary propulsion

This paper presents the results of an effort to demonstrate the technology readiness of a long-life multipropellant resistojet for space station auxiliary propulsion. Experiments were performed to evaluate the compatibility of grain-stabilized platinum tubes at temperatures up to 1400 deg C in environments of CO2, CH4, NH3, H2O, and H2. All samples tested showed extrapolated lifetimes in excess of 10,000 hr based on 10 percent mass loss as end-of-life. However, samples tested in an ammonia atmosphere at 1400 deg C showed severe pitting, which raised concerns about the compatibility of grain-stabilized platinum with ammonia-containing atmospheres. Additional tests showed that reducing the metal temperature to about 900 deg C (+ or - 100 deg C) significantly reduced this adverse effect.

Morren, W. E.↗
NASA NTRS1987

A 2000-hour cyclic endurance test of a laboratory model multipropellant resistojet

The technological readiness of a long-life multipropellant resistojet for space station auxiliary propulsion is demonstrated. A laboratory model resistojet made from grain-stabilized platinum served as a test bed to evaluate the design characteristics, fabrication methods, and operating strategies for an engineering model multipropellant resistojet developed under contract by the Rocketdyne Division of Rockwell International and Technion Incorporated. The laboratory model thruster was subjected to a 2000-hr, 2400-thermal-cycle endurance test using carbon dioxide propellant. Maximum thruster temperatures were approximately 1400 C. The post-test analyses of the laboratory model thruster included an investigation of component microstructures. Significant observations from the laboratory model thruster are discussed as they relate to the design of the engineering model thruster.

Morren, W. Earl↗
NASA NTRS1984

ACEE composite structures technology

The NASA Aircraft Energy Efficiency (ACEE) Composite Primary Aircraft Structures Program has made significant progress in the development of technology for advanced composites in commercial aircraft. Commercial airframe manufacturers have demonstrated technology readiness and cost effectiveness of advanced composites for secondary and medium primary components and have initiated a concerted program to develop the data base required for efficient application to safety-of-flight wing and fuselage structures. Oral presentations were compiled into five papers. Topics addressed include: damage tolerance and failsafe testing of composite vertical stabilizer; optimization of composite multi-row bolted joints; large wing joint demonstation components; and joints and cutouts in fuselage structure.

Klotzsche, M.↗
NASA NTRS1987

Space Station propulsion system test bed and control system testing results

The test bed fabricated to demonstrate hydrogen/oxygen propulsion technology readiness for the IOC Space Station application is described and test results are presented. The reliability and safety of the O2/H2 system was demonstrated with blowdowns and thruster firings. The flexibility of the system was demonstrated through the addition of an electrolysis supply module.

Norman, A. M.↗
NASA NTRS1987

2000-hour cyclic endurance test of a laboratory model multipropellant resistojet

The technological readiness of a long-life multipropellant resistojet for space station auxiliary propulsion is demonstrated. A laboratory model resistojet made from grain-stabilized platinum served as a test bed to evaluate the design characteristics, fabrication methods, and operating strategies for an engineering model multipropellant resistojet developed under contract by the Rocketdyne Division of Rockwell International and Technion Incorporated. The laboratory model thruster was subjected to a 2000-hr, 2400-thermal-cycle endurance test using carbon dioxide propellant. Maximum thruster temperatures were approximately 1400 C. The post-test analyses of the laboratory model thruster included an investigation of component microstructures. Significant observations from the laboratory model thruster are discussed as they relate to the design of the engineering model thruster.

Morren, W. Earl↗
NASA NTRS1987

Space station propulsion technology

The objectives of this program are to provide a demonstration of hydrogen/oxygen propulsion technology readiness for the initial operational capability (IOC) space station application, specifically gaseous hydrogen/oxygen and warm hydrogen thruster concepts, and to establish a means for evolving from the IOC space station propulsion system (SSPS) to that required to support and interface with advanced station functions. These objectives were met by analytical studies and by furnishing a propulsion test bed to the Marshall Space Flight Center for testing.

Norman, A. M.↗
NASA NTRS1988

Advanced EVA system design requirements study

The results are presented of a study to identify specific criteria regarding space station extravehicular activity system (EVAS) hardware requirements. Key EVA design issues include maintainability, technology readiness, LSS volume vs. EVA time available, suit pressure/cabin pressure relationship and productivity effects, crew autonomy, integration of EVA as a program resource, and standardization of task interfaces. A variety of DOD EVA systems issues were taken into consideration. Recommendations include: (1) crew limitations, not hardware limitations; (2) capability to perform all of 15 generic missions; (3) 90 days on-orbit maintainability with 50 percent duty cycle as minimum; and (4) use by payload sponsors of JSC document 10615A plus a Generic Tool Kit and Specialized Tool Kit description. EVA baseline design requirements and criteria, including requirements of various subsystems, are outlined. Space station/EVA system interface requirements and EVA accommodations are discussed in the areas of atmosphere composition and pressure, communications, data management, logistics, safe haven, SS exterior and interior requirements, and SS airlock.

Woods, T. G.↗
NASA NTRS1988

Status of high power electric propulsion technology

The growing emphasis on very challenging missions and the anticipated availability of high power levels in space have led to renewed interest in high power electric propulsion. The status of high power electric propulsion technology and its applicability to various missions are reviewed. The major thruster and system technology issues are identified which must be addressed in a focussed program in order to assure technology readiness for these missions.

Byers, David C.↗
NASA NTRS1987

An advanced imaging space telescope concept

This paper describes the results of a recent study of possible configurations for a next-generation optical space telescope with order-of-magnitude improvements over the Hubble Space Telescope. Overall configuration characteristics including optical performance, weights, and dimensions are given. Launch vehicle packaging concepts are described, and a scenario for orbital assembly developed. Finally, an assessment of technology readiness is provided.

Krim, Michael H.↗
NASA NTRS1988

The RSRA/X-Wing experiment - A status report

This paper reports on the current status of the NASA/Army Rotor Systems Research Aircraft (RSRA)/X-Wing Experiment program designed to demonstrate the technology readiness of the X-Wing concept for a prototype vehicle. Program accomplishments, test results on all of the necessary major hardware elements, and the results of flight tests are described. Future wind tunnel testing of the full-scale rotor system in the NASA NF SAC facility is presently being planned; these tests must be completed before an objective assessment can be made regarding the viability of the RSRA/X-Wing concept for an operational aircraft.

Lane, James W.↗
NASA NTRS1989

Mercury ion thruster technology

The Mercury Ion Thruster Technology program was an investigation for improving the understanding of state-of-the-art mercury ion thrusters. Emphasis was placed on optimizing the performance and simplifying the design of the 30 cm diameter ring-cusp discharge chamber. Thruster performance was improved considerably; the baseline beam-ion production cost of the optimized configuration was reduced to Epsilon (sub i) perspective to 130 eV/ion. At a discharge propellant-utilization efficiency of 95 percent, the beam-ion production cost was reduced to about 155 eV/ion, representing a reduction of about 40 eV/ion over the corresponding value for the 30 cm diameter J-series thruster. Comprehensive Langmuir-probe surveys were obtained and compared with similar measurements for a J-series thruster. A successful volume-averaging scheme was developed to correlate thruster performance with the dominant plasma processes that prevail in the two thruster designs. The average Maxwellian electron temperature in the optimized ring-cusp design is as much as 1 eV higher than it is in the J-series thruster. Advances in ion-extraction electrode fabrication technology were made by improving materials selection criteria, hydroforming and stress-relieving tooling, and fabrications procedures. An ion-extraction performance study was conducted to assess the effect of screen aperture size on ion-optics performance and to verify the effectiveness of a beam-vectoring model for three-grid ion optics. An assessment of the technology readiness of the J-series thruster was completed, and operation of an 8 cm IAPS thruster using a simplified power processor was demonstrated.

Beattie, J. R.↗
NASA NTRS1989

Space station propulsion test bed

A test bed was fabricated to demonstrate hydrogen/oxygen propulsion technology readiness for the intital operating configuration (IOC) space station application. The test bed propulsion module and computer control system were delivered in December 1985, but activation was delayed until mid-1986 while the propulsion system baseline for the station was reexamined. A new baseline was selected with hydrogen/oxygen thruster modules supplied with gas produced by electrolysis of waste water from the space shuttle and space station. As a result, an electrolysis module was designed, fabricated, and added to the test bed to provide an end-to-end simulation of the baseline system. Subsequent testing of the test bed propulsion and electrolysis modules provided an end-to-end demonstration of the complete space station propulsion system, including thruster hot firings using the oxygen and hydrogen generated from electrolysis of water. Complete autonomous control and operation of all test bed components by the microprocessor control system designed and delivered during the program was demonstrated. The technical readiness of the system is now firmly established.

Briley, G. L.↗
NASA NTRS1987

The human role in space (THURIS) applications study. Final briefing

The THURIS (The Human Role in Space) application is an iterative process involving successive assessments of man/machine mixes in terms of performance, cost and technology to arrive at an optimum man/machine mode for the mission application. The process begins with user inputs which define the mission in terms of an event sequence and performance time requirements. The desired initial operational capability date is also an input requirement. THURIS terms and definitions (e.g., generic activities) are applied to the input data converting it into a form which can be analyzed using the THURIS cost model outputs. The cost model produces tabular and graphical outputs for determining the relative cost-effectiveness of a given man/machine mode and generic activity. A technology database is provided to enable assessment of support equipment availability for selected man/machine modes. If technology gaps exist for an application, the database contains information supportive of further investigation into the relevant technologies. The present study concentrated on testing and enhancing the THURIS cost model and subordinate data files and developing a technology database which interfaces directly with the user via technology readiness displays. This effort has resulted in a more powerful, easy-to-use applications system for optimization of man/machine roles. Volume 1 is an executive summary.

Maybee, George W.↗
NASA NTRS1988

Large-scale Advanced Prop-fan (LAP) technology assessment report

The technologically significant findings and accomplishments of the Large Scale Advanced Prop-Fan (LAP) program in the areas of aerodynamics, aeroelasticity, acoustics and materials and fabrication are described. The extent to which the program goals related to these disciplines were achieved is discussed, and recommendations for additional research are presented. The LAP program consisted of the design, manufacture and testing of a near full-scale Prop-Fan or advanced turboprop capable of operating efficiently at speeds to Mach .8. An aeroelastically scaled model of the LAP was also designed and fabricated. The goal of the program was to acquire data on Prop-Fan performance that would indicate the technology readiness of Prop-Fans for practical applications in commercial and military aviation.

Degeorge, C. L.↗
NASA NTRS1990

Advanced Launch System (ALS): Electrical actuation and power systems improve operability and cost picture

To obtain the Advanced Launch System (ALS) primary goals of reduced costs and improved operability, there must be significant reductions in the launch operations and servicing requirements relative to current vehicle designs and practices. One of the primary methods for achieving these goals is by using vehicle electrical power system and controls for all actuation and avionics requirements. A brief status review of the ALS and its associated Advanced Development Program is presented to demonstrate maturation of those technologies that will help meet the overall operability and cost goals. The electric power and actuation systems are highlighted as a specific technology ready not only to meet the stringent ALS goals (cryogenic field valves and thrust vector controls with peak power demands to 75 hp), but also those of other launch vehicles, military and civilian aircraft, lunar/Martian vehicles, and a multitude of commercial applications.

Sundberg, Gale R.↗