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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 1,045 records · Page 58
All sourcesNASA NTRSDOE OSTI
NASA NTRS1977

Development of an advanced combined iodine dispenser/detector

Injection of iodine into water is widely used to control microbial growth. An entirely automated device for I2 injection has been developed for spacecraft application. Transfer of I2 into the water from a concentrated form is controlled electrochemically via feedback from an integrated photometric I2 level detector. All components are contained within a package weighing only 1.23 kg (2.7 lb) dry, which occupies only 1213 cu cm (74 cu in) of space, and which has the capacity to iodinate 10,900 kg (24,000 lb) of water of 5 ppm. These features exceed design specifications. The device performed satisfactorily during extended testing at variable water flow rates and temperatures. Designed to meet specifications of the Shuttle Orbiter, the device will find application in the regenerative water systems of advanced spacecraft.

Lantz, J. B.↗
NASA NTRS1978

Advanced subsystems development

The concept design for a small (less than 10 MWe) solar thermal electric generating plant was completed using projected 1985 technology. The systems requirements were defined and specified. The components, including an engineering prototype for one 15 kWe module of the generating plant, were conceptually designed. Significant features of the small solar thermal power plant were identified as the following: (1) 15 kWe Stirling-cycle engine/alternator with constant power output; (2) 10 meter point-focusing paraboloidal concentrator with cantilevered cellular glass reflecting panels; (3) primary heat pipe with 800 C output solar cavity receiver; (4) secondary heat pipe with molten salt thermal energy storage unit; (5) electric energy transport system; and (6) advanced battery energy storage capability.

Livingston, F. R.↗
NASA NTRS1979

The cost benefits of the Spacelab system to scientific investigations and space applications

Cost advantages of the Spacelab system to scientific experiments in space and space operations are presented. The payload integration concepts developed for Spacelab are examined, and it is shown that Spacelab and Shuttle integration, communications and data processing, launch support requirements and flight operations will provide a considerable savings in the costs of space research relative to previous space systems. Spacelab modular design, incorporating features such as standard payload interfaces, optional mission dependent equipment and standard services, such as the Experiment Computer Operating System, is shown to offer the user a wider range of services than previous programs, also at significantly lower costs. It is concluded that the Spacelab system will greatly reduce the costs and broaden the opportunities for scientific investigation in space.

Jean, O. C.↗
NASA NTRS1980

New position-sensitive hard X-ray spectrometer

The design and features of a new prototype Lixiscope (Low intensity X-ray imaging scope) is described. It is shown that in addition to good spatial and temporal resolution in the 20 keV to 200 keV region, it is capable of single-photon counting, imaging as well as good energy resolution. It is concluded that the device is well suited for future low-flux applications in astronomy, medicine, and industry.

Yin, L. I.↗
NASA NTRS1981

A programing system for research and applications in structural optimization

The flexibility necessary for such diverse utilizations is achieved by combining, in a modular manner, a state-of-the-art optimization program, a production level structural analysis program, and user supplied and problem dependent interface programs. Standard utility capabilities in modern computer operating systems are used to integrate these programs. This approach results in flexibility of the optimization procedure organization and versatility in the formulation of constraints and design variables. Features shown in numerical examples include: variability of structural layout and overall shape geometry, static strength and stiffness constraints, local buckling failure, and vibration constraints.

Sobieszczanski-Sobieski, J.↗
NASA NTRS1981

A programing system for research and applications in structural optimization

The paper describes a computer programming system designed to be used for methodology research as well as applications in structural optimization. The flexibility necessary for such diverse utilizations is achieved by combining, in a modular manner, a state-of-the-art optimization program, a production level structural analysis program, and user supplied and problem dependent interface programs. Standard utility capabilities existing in modern computer operating systems are used to integrate these programs. This approach results in flexibility of the optimization procedure organization and versatility in the formulation of contraints and design variables. Features shown in numerical examples include: (1) variability of structural layout and overall shape geometry, (2) static strength and stiffness constraints, (3) local buckling failure, and (4) vibration constraints. The paper concludes with a review of the further development trends of this programing system.

Sobieszczanski-Sobieski, J.↗
NASA NTRS1982

Nuclear electric propulsion /NEP/ spacecraft for the outer planet orbiter mission

The design, operating features, and a possible Neptune orbit for the spacecraft powered by the SP-100 nuclear electric propulsion (NEP) system under study by NASA and the DOE are described. The system features a reactor and a payload situated on opposite ends of a 0.5 m diam, 11 m long astromast. Mercury-ion thrusters are located beneath the reactor for side thrusting, and no contamination of the payload or obstruction of the viewing angles for scientific objectives occurs with the system, which would not degrade in performance even under high insolation during near-sun maneuvers. Results of a theoretical study of earth escapes are presented to show that an NEP powered spiral trajectory out of a 700 km Shuttle orbit and using a Triton gravity assist would be superior to departing from a 300 km orbit with a Centaur boost. The mission profile includes a 1249 kg Galileo payload. The SP-100 has a 1.4 MWth reactor with UO2 fuel tiles and weighs 19,904 kg.

Garrison, P. W.↗
NASA NTRS1985

Magnetic shear. I - Hale region 16918

The present investigation is concerned with a study of the large-scale morphological and dynamical properties of selected active areas of the sun, taking into account a combination of data from the UVSP experiment on the Solar Maximum Mission (SMM) spacecraft and ground-based data. The area considered comprises NOAA active regions 2516, 2517, and 2519 (Hale regions 16918 and the nothern portions of 16923), whose disk passage occurred during rotation 1696 in the latter half of June 1980. The method of analysis is discussed, and the general characteristics of the regions are examined. Attention is given to the designation of features, magnetograms, spectroheliograms, Dopplergrams, H-alpha filaments, and H-alpha fibrils.

Athay, R. G.↗
NASA NTRS1985

An experimental reciprocating expander for cryocooler application

An experimental reciprocating expander was designed with features appropriate for cryocooler cycles. The expander has a displacer piston, simple valves, and a hydraulic/pneumatic stroking mechanism. The expander has a valve in head configuration with the valves extending out the bottom of the vacuum enclosure while the piston extends out the top. The expander was tested using a CTI 1400 liquefier to supply 13 atm in the temperature range 4.2 to 12 K. Expander efficiency was measured in the range 84 to 93% while operating the apparatus as a supercritical wet expander and in the range 91 to 93% aa a single phase expander. The apparatus can also be modified to operate as a compressor for saturated helium vapor.

Minta, M.↗
NASA NTRS1986

A Sensor Failure Simulator for Control System Reliability Studies

A real-time Sensor Failure Simulator (SFS) was designed and assembled for the Advanced Detection, Isolation, and Accommodation (ADIA) program. Various designs were considered. The design chosen features an IBM-PC/XT. The PC is used to drive analog circuitry for simulating sensor failures in real-time. A user defined scenario describes the failure simulation for each of the five incoming sensor signals. Capabilities exist for editing, saving, and retrieving the failure scenarios. The SFS has been tested closed-loop with the Controls Interface and Monitoring (CIM) unit, the ADIA control, and a real-time F100 hybrid simulation. From a productivity viewpoint, the menu driven user interface has proven to be efficient and easy to use. From a real-time viewpoint, the software controlling the simulation loop executes at greater than 100 cycles/sec.

Melcher, K. J.↗
NASA NTRS1986

Advanced manned earth-to-orbit vehicle

Advanced manned launch vehicle concepts which are designed to meet the space transportation architecture and mission needs for the early 21st century are described. Concepts are described which are based both on modest (evolutionary) and revolutionary advancements in performance technologies but with emphasis on defining operations cost. Design options feature fully reusable, vertical-takeoff, horizontal-landing, rocket-powered concepts and include a variety of possible staging arrangements depending on the desired mission emphasis and the available technologies.

Eldred, Charles H.↗
NASA NTRS1988

Mission telemetry system monitor: A real-time knowledge-based system

The Galileo Mission Telemetry System (MTS) has a cluster of computer subsystems configured as a star network. The MTS handles the real-time processing of spacecraft telemetry and ground monitor data. Large volumes of status and fault messages are generated as a result of changes in the system environment. These messages are triggered by the conditions that exist on any one particular subsystem or device. The order of message generation is in time sequence and does not always correlate to the function sequence of active processes. A significant number of messages provide context with varying degrees of uncertainty. As such, highly skilled telemetry controllers are required to regularly go through high volumes of messages generated by the MTS to identify, diagnose, and isolate faults. A knowledge-based system prototype is being developed to monitor the Galileo Mission Telemetry System performance. The system design approach features temporal reasoning, uncertainty management, and intelligent graphic user interfaces.

Mouneimne, Samih A.↗
NASA NTRS1989

Multihundred-Kilowatt Rotary Electrical-Transfer Device

Roll-ring electrical-power-transfer device capable of transferring high power (hundreds of kilowatts) through rotating connection. Roll-ring assembly transfers up to 500 V at 200 A per circuit, either dc or ac to frequencies of 20 kHz. Assembly has eight power circuits. Outstanding feature of design very low power loss - only 16 W per circuit while transferring 100 kW. Terrestrial application requiring power to transfer through rotating joint with low losses uses roll-ring technology. Used in air or vacuum with no design changes.

Jacobson, Peter↗
NASA NTRS1988

Large scale prop-fan structural design study. Volume 1: Initial concepts

In recent years, considerable attention has been directed toward improving aircraft fuel consumption. Studies have shown that the inherent efficiency advantage that turboprop propulsion systems have demonstrated at lower cruise speeds may now be extended to the higher speeds of today's turbofan and turbojet-powered aircraft. To achieve this goal, new propeller designs will require features such as thin, high speed airfoils and aerodynamic sweep, features currently found only in wing designs for high speed aircraft. This is Volume 1 of a 2 volume study to establish structural concepts for such advanced propeller blades, to define their structural properties, to identify any new design, analysis, or fabrication techniques which were required, and to determine the structural tradeoffs involved with several blade shapes selected primarily on the basis of aero/acoustic design considerations. The feasibility of fabricating and testing dynamically scaled models of these blades for aeroelastic testing was also established. The preliminary design of a blade suitable for flight use in a testbed advanced turboprop was conducted and is described in Volume 2.

Billman, L. C.↗
NASA NTRS1988

Large scale prop-fan structural design study. Volume 2: Preliminary design of SR-7

In recent years, considerable attention has been directed toward improving aircraft fuel consumption. Studies have shown that the inherent efficiency advantage that turboprop propulsion systems have demonstrated at lower cruise speeds may now be extended to the higher speeds of today's turbofan and turbojet-powered aircraft. To achieve this goal, new propeller designs will require features such as thin, high speed airfoils and aerodynamic sweep, features currently found only in wing designs for high speed aircraft. This is Volume 2 of a 2 volume study to establish structural concepts for such advanced propeller blades, to define their structural properties, to identify any new design, analysis, or fabrication techniques which were required, and to determine the structural tradeoffs involved with several blade shapes selected primarily on the basis of aero/acoustic design considerations. The feasibility of fabricating and testing dynamically scaled models of these blades for aeroelastic testing was also established. The preliminary design of a blade suitable for flight use in a testbed advanced turboprop was conducted and is described.

Billman, L. C.↗
NASA NTRS1990

Data distribution satellite system architecture concept

This paper describes a future communications satellite system architecture concept called the Data Distribution Satellite (DDS). The DDS is envisioned as a new system to be used as an adjunct to TDRS/TDAS for distributing new NASA science data throughout the U.S. as well as internationally. The DDS would also provide networking capability for interchange of science database files among science users and NASA archive depositories. Experimenters would be able to access and control their experimental packages remotely, relieving astronaut workload. This paper gives a conceptual system design based on year 1995 technology. Features of the design include use of Ku and Ka-bands, use of fixed spot beams, 2 Gb/s throughput, and on-board demodulation and switching. The satellite dry mass is 1,300 kg and end-of-life power is 4 kW.

Price, Kent M.↗
NASA NTRS1989

Design concepts for the Centrifuge Facility Life Sciences Glovebox

The Life Sciences Glovebox will provide the bioisolated environment to support on-orbit operations involving non-human live specimens and samples for human life sceinces experiments. It will be part of the Centrifuge Facility, in which animal and plant specimens are housed in bioisolated Habitat modules and transported to the Glovebox as part of the experiment protocols supported by the crew. At the Glovebox, up to two crew members and two habitat modules must be accommodated to provide flexibility and support optimal operations. This paper will present several innovative design concepts that attempt to satisfy the basic Glovebox requirements. These concepts were evaluated for ergonomics and ease of operations using computer modeling and full-scale mockups. The more promising ideas were presented to scientists and astronauts for their evaluation. Their comments, and the results from other evaluations are presented. Based on the evaluations, the authors recommend designs and features that will help optimize crew performance and facilitate science accommodations, and specify problem areas that require further study.

Sun, Sidney C.↗
NASA NTRS1989

A high efficiency motor/generator for magnetically suspended flywheel energy storage system

The authors discuss the theory and design of a brushless direct current motor for use in a flywheel energy storage system. The motor design is optimized for a nominal 4.5-in outside diameter operating within a speed range of 33,000-66,000 revolutions per minute with a 140-V maximum supply voltage. The equations which govern the motor's operation are used to compute a series of acceptable design parameter combinations for ideal operation. Engineering tradeoffs are then performed to minimize the irrecoverable energy loss while remaining within the design constraint boundaries. A final integrated structural design whose features allow it to be incorporated with the 500-Wh magnetically suspended flywheel is presented.

Niemeyer, W. L.↗