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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 55 records · Page 3
All sourcesNASA NTRSDOE OSTI
NASA NTRS1977

Viking Mars hydrazine terminal descent engine thermal design considerations

A description is given of some of the more significant thermal design considerations employed in the development and qualification of the monopropellant hydrazine terminal descent engines on the Viking Mars lander spacecraft. The terminal descent engine operates in a blowdown and throttling mode, which results in an operating thrust range of 638 to 90 lbf. Martian entry thermal design boundary conditions are described, along with resulting radiative and conductive engine thermal isolation hardware. Test results are presented, showing engine thermal design performance as compared with specified requirements. General engine materials of construction are described, along with Hastelloy B shell structural characteristics, which were extended to 2000 F by test and are compared with limited existing MIL-HDBK-5 data. Subscale test results are presented, showing the maximum catalyst bed cylinder design temperature of 1970 F. Test results also are presented, showing local reactor internal convective heat-transfer coefficients. Such data are unique, since the engine employs a completely radial flow catalyst bed design. This design approach is the first of its kind in the monopropellant hydrazine gas generator field to be flight qualified.

Cunningham, C. R.↗
NASA NTRS1994

Design considerations and strategies for lunar-based observations

This paper addresses the design considerations and strategies for astrophysical observations as key elements of an international solar system exploration program. Emphasis is placed on the technical and programmatic challenges and opportunities associated with an evolving program of lunar-based astronomy. Both robotic and human tended facilities are discussed ranging from relatively small meter-class transit telescopes to large interferometer and filled-aperture systems.

Snoddy, William C.↗
NASA NTRS1993

Mars Relays Satellite Orbit Design Considerations for Global Support of Robotic Surface Missions

This paper discusses orbit design considerations for Mars relay satellite (MRS)support of globally distributed robotic surface missions. The orbit results reported in this paper are derived from studies of MRS support for two types of Mars robotic surface missions: 1) the mars Environmental Survey (MESUR) mission, which in its current definition would deploy a global network of up to 16 small landers, and 2)a Small Mars Sample Return (SMSR) mission, which included four globally distributed landers, each with a return stage and one or two rovers, and up to four additional sets of lander/rover elements in an extended mission phase.

Robitics Mars↗
NASA NTRS1976

Design Considerations for Laminar Flow Control Aircraft

A study was conducted to investigate major design considerations involved in the application of laminar flow control to the wings and empennage of long range subsonic transport aircraft compatible with initial operation in 1985. For commercial transports with a design mission range of 10,186 km (5500 n mil) and a payload of 200 passengers, parametric configuration analyses were conducted to evaluate the effect of aircraft performance, operational, and geometric parameters on fuel efficiency. Study results indicate that major design goals for aircraft optimization include maximization of aspect ratio and wing loading and minimization of wing sweep consistent with wing volume and airport performance requirements.

Sturgeon, R. F.↗
NASA NTRS2011

Design Considerations for a Launch Vehicle Development Flight Instrumentation System

When embarking into the design of a new launch vehicle, engineering models of expected vehicle performance are always generated. While many models are well established and understood, some models contain design features that are only marginally known. Unfortunately, these analytical models produce uncertainties in design margins. The best way to answer these analytical issues is with vehicle level testing. The National Aeronautics and Space Administration respond to these uncertainties by using a vehicle level system called the Development Flight Instrumentation, or DFI. This DFI system can be simple to implement, with only a few measurements, or it may be a sophisticated system with hundreds of measurement and video, without a recording capability. From experience with DFI systems, DFI never goes away. The system is renamed and allowed to continue, in most cases. Proper system design can aid the transition to future data requirements. This paper will discuss design features that need to be considered when developing a DFI system for a launch vehicle. It will briefly review the data acquisition units, sensors, multiplexers and recorders, telemetry components and harnessing. It will present a reasonable set of requirements which should be implemented in the beginning of the program in order to start the design. It will discuss a simplistic DFI architecture that could be the basis for the next NASA launch vehicle. This will be followed by a discussion of the "experiences gained" from a past DFI system implementation, such as the very successful Ares I-X test flight. Application of these design considerations may not work for every situation, but they may direct a path toward success or at least make one pause and ask the right questions.

Johnson, Martin L.↗
NASA NTRS1972

Design considerations for combined radiation effects facilities for twelve year outer planet spacecraft voyages

The design considerations influencing the choice and utility of environmental simulation methods and facilities are described, insofar as they relate to the requirements imposed on outer planet spacecraft because of radiation environments to be expected. Possible means for duplicating the radioisotope thermoelectric generator radiation environment, and for duplicating the effects of the trapped radiation belt environment are described, together with an assessment of radiation levels to be expected in the vicinity of an environmental testing chamber when in use.

Miller, C. G.↗
NASA NTRS1979

Radiation design considerations for advanced Jupiter spacecraft

This paper considers one aspect of the complex radiation design considerations for planetary spacecraft, namely the approach used for solving the effects of radiation on materials problems. An overview of the approach developed at JPL for Voyager, and currently being used on Galileo, is treated briefly. Examples of the postulated Jovian charged particle levels are given. The types of computer analyses codes used, the mass shielding techniques that evolved and the recommended shielding techniques for future planetary spacecraft are treated.

Bouquet, F. L.↗
NASA NTRS2009

CSM RCS Design Considerations and Failure Modes

Objectives include: a) Define major Command and Service Module (CSM) design considerations; b) List Command Module (CM) RCS failures and lessons learned; and c) List Service Module (SM) RCS failures and lessons learned.

Interbartolo, Michael↗
NASA NTRS2009

Apollo CSM Power Generation System Design Considerations, Failure Modes and Lessons Learned

The objectives of this slide presentation are to: review the basic design criteria for fuel cells (FC's), review design considerations during developmental phase that affected Block I and Block II vehicles, summarize the conditions that led to the failure of components in the FC's, and state the solution implemented for each failure. It reviews the location of the fuel cells, the fuel cell theory the design criteria going into development phase and coming from the development phase, failures and solutions of Block I and II, and the lessons learned.

Interbartolo, Michael↗
NASA NTRS2009

Lunar Module Wiring Design Considerations and Failure Modes

This slide presentation reviews the considerations for the design of wiring for the Lunar Module. Included are a review of the choice of conductors and insulations, the wire splicing (i.e., crimping, and soldering), the wire connectors, and the fabrication of the wire harnesses. The problems in fabrication include the wires being the wrong length, the damage due to the sharp edges, the requried use of temproary protective covers and inadequate training. The problems in the wire harness installation include damge from sharp eges, work on adjacent harnesses, connector damage, and breaking wires. Engineering suggestions from the Apollo-era in reference to the conductors that are reviewed include: the use of plated conductors, and the use of alloys for stronger wiring. In refernce to insulation, the suggestions from Apollo era include the use of polymer tape-wrap wire insulation due to the light weight, however, other types of modern insulation might be more cost-effective. In reference to wire splices and terminal boards the suggestions from the Apollo Era include the use of crimp splices as superior to solder splices, joining multiple wire to a common point using modular plug-ins might be more reliable, but are heavier than crimp splicing. For connectors, the lessons from the Apollo era indicate that a rear environmental seal that does not require additional potting is preferred, and pins should be crimped or welded to the incoming wires and be removable from the rear of the connector.

Interbartolo, Michael↗
NASA NTRS1992

Operation and design considerations for unsteady data acquisition with PC-based systems in high Reynolds number hypersonic flowfields

Operation and design considerations for personal-computer-based data acquisition are analyzed, and a system is created that is portable, inexpensive, and capable of high-frequency response. This system performed well when given an extensive analysis of the characteristics of the radio-frequency noise in the test environment. The system architecture is well-suited for support of high-frequency data acquisition from both pressure transducers and high-frequency-response thermocouple gauges. As configured, the system provides a data resolution of approximately 0.09 psia and 0.56 F. Considering the constraints placed upon this design, this data resolution is acceptable. The $5000 budget did require use of an existing PC and rental of signal-conditioning equipment.

Flanagan, M. J., Jr.↗
NASA NTRS1987

Design Considerations for High-Speed Control Systems

Existing hardware integrated into versatile, high-speed control system. Report discusses five global design considerations to integrate array-processor, multimicroprocessor, and host-computer system architectures into versatile, high-speed controllers. Such controllers are capable of control throughputs as high as 36 MHz for 8-bit bytes and maintain constant interaction with non-real-time or user environment. Application example, architecture of high-speed, closed-loop controller used to control helicopter vibration actively discussed.

Jacklin, S. A.↗
NASA NTRS1995

Design Considerations for the Next Generation of General Aviation Designs

This paper discusses the results of research conducted at NASA Langley Research Center during two summer programs during 1994 and 1995. These programs were the NASA Advanced Design Program and the Langley Research Summer Scholars program. The work was incorporated in a three phase project at Embry-Riddle Aeronautical University which focused on development of the next generation Primary Flight Trainer, as well as in ERAU's participation in the AGATE General Aviation Design Competition. The project was conducted as part of the ERAU/NASA/USRA Advanced Design Program in Aeronautics as well as the AGATE competition. A design study was completed which encompassed the incorporation of existing conventional technologies and advanced technologies into PFT designs and advanced GA aircraft designs. Multiple aircraft configurations were also examined throughout the ADP/AGATE. Evaluations of the various technologies and configurations studied will be made and recommendations will be included.

Marchesseault, Brian D.↗
NASA NTRS1985

Crashworthy design considerations for general aviation seats

This report summarizes the experimental research conducted at the NASA Langley Research Center on general aviation seat and occupant crash response and discusses seat design considerations. Included are typical floor acceleration pulses from general aviation airplane crash tests, the performance of typical general aviation seats in a simulated crash environment, and the performance of prototype energy absorbing (EA) seat designs. Static and dynamic seat testing procedures and test facilities are discussed. Also presented are results from a series of dynamic tests of typical general aviation seats and prototype EA seats.

Alfaro-Bou, E.↗