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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 901 records · Page 50
All sourcesNASA NTRSDOE OSTI
NASA NTRSDate not supplied

Restoration of NASA's Mobile Analytical Lunar Platform (MALP) as a Prototype Science Exploration Device using a Public, Private, Academic (PPA) Model

A prototype 6-wheeled rover originally developed by NASA JSC for astronaut transport has been modernized and augmented to support concepts for telerobotic exploration of the lunar surface. The ongoing project has employed teams of undergraduate senior engineering students at Texas A&M University (TAMU) to retrofit the Mobile Analytical Lunar Platform (MALP) with wireless technology for telerobotic operations, and to add a robotic arm for regolith sample collection, sieving, storage and transportation.

Telerobotic Rover↗
NASA NTRS1986

Bipropellant rocket exhaust plume analysis on the Galileo spacecraft

This paper describes efforts to quantify the contaminant flow field produced by 10 N thrust bipropellant rocket engines used on the Galileo spacecraft. The prediction of the composition of the rocket exhaust by conventional techniques is found to be inadequate to explain experimental observations of contaminant deposition on moderately cold (200 K) surfaces. It is hypothesized that low volatility contaminants are formed by chemical reactions which occur on the surfaces. The flow field calculations performed using the direct simulation Monte Carlo method give the expected result that the use of line-of-sight plume shields may have very little effect on the flux of vapor phase contaminant species to a surface, especially if the plume shields are located so close to the engine that the interaction of the plume with the shield is in the transition flow regime. It is shown that significant variations in the exhaust plume composition caused by nonequilibrium effects in the flow field lead to very low concentrations of species which have high molecular weights in the more rarefied regions of the flow field. Recommendations for the design of spacecraft plume shields and further work are made.

Guernsey, C. S.↗
NASA NTRS2005

Joint Test Protocol for Validation of Alternative Low-Emission Surface Preparation/Depainting Technologies for Structural Steel

Headquarters National Aeronautics and Space Administration (NASA) chartered the Acquisition Pollution Prevention (AP2) Office to coordinate agency activities affecting pollution prevention issues identified during system and component acquisition and sustainment processes. The primary objectives of the AP2 Office are to: (1) Reduce or eliminate the use of hazardous materials (HazMats) or hazardous processes at manufacturing, remanufacturing, and sustainment locations. (2) A void duplication of effort in actions required to reduce or eliminate HazMats through joint center cooperation and technology sharing. This project will identify, evaluate and approve alternative surface preparation technologies for use at NASA and Air Force Space Command (AFSPC) installations. Materials and processes will be evaluated with the goal of selecting those processes that will improve corrosion protection at critical systems, facilitate easier maintenance activity, extend maintenance cycles, eliminate flight hardware contamination and reduce the amount of hazardous waste generated. This Joint Test Protocol (JTP) contains the critical requirements and tests necessary to qualify alternative Low-Emission Surface Preparation/Depainting Technologies for Structural Steel Applications. These tests were derived from engineering, performance, and operational impact (supportability) requirements defined by a consensus of NASA and Air Force Space Command (AFSPC) participants. The Field Test Plan (FTP), entitled Joint Test Protocol for Validation of Alternative Low Emission Surface Preparation/Depainting Technologies for Structural Steel, prepared by ITB, defines the field evaluation and testing requirements for validating alternative surface preparation/depainting technologies and supplements the JTP.

Lewis, Pattie↗
NASA NTRS1992

Workshop on Grid Generation and Related Areas

A collection of papers given at the Workshop on Grid Generation and Related Areas is presented. The purpose of this workshop was to assemble engineers and scientists who are currently working on grid generation for computational fluid dynamics (CFD), surface modeling, and related areas. The objectives were to provide an informal forum on grid generation and related topics, to assess user experience, to identify needs, and to help promote synergy among engineers and scientists working in this area. The workshop consisted of four sessions representative of grid generation and surface modeling research and application within NASA LeRC. Each session contained presentations and an open discussion period.

Source record↗
NASA NTRS1985

Properties of coated and modified surfaces

The ability to create surface and near-surface properties distinct from the bulk properties of a material by means of coating or surface modification techniques is an important new field of development for engineering materials, encompassing ion implantation, plasma processing, reactive deposition methods, ion beam deposition and modification, molecular beam epitaxy, and fast quench thermal processing. Attention is given to specific areas of process control which illustrate (1) the use of process development to control material properties, (2) the importance of surface modification and coating to the tribology and ion-surface interactions of semiconductor film growth, and (3) recent findings in surface science which exemplify potential applications of ion-surface interactions that generate novel material qualities.

Mattox, D. M.↗
NASA NTRS2013

The Tailoring of Traditional Systems Engineering for the Morpheus Project

NASA's Morpheus Project has developed and tested a prototype planetary lander capable of vertical takeoff and landing that is designed to serve as a testbed for advanced spacecraft technologies. The lander vehicle, propelled by a LOX/Methane engine and sized to carry a 500kg payload to the lunar surface, provides a platform for bringing technologies from the laboratory into an integrated flight system at relatively low cost. From the beginning, one of goals for the Morpheus Project was to streamline agency processes and practices. The Morpheus project accepted a challenge to tailor the traditional NASA systems engineering approach in a way that would be appropriate for a lower cost, rapid prototype engineering effort, but retain the essence of the guiding principles. The team has produced innovative ways to create an infrastructure and approach that would challenge existing systems engineering processes while still enabling successful implementation of the current Morpheus Project. This paper describes the tailored systems engineering approach for the Morpheus project, including the processes, tools, and amount of rigor employed over the project's multiple lifecycles since the project began in FY11. Lessons learned from these trials have the potential to be scaled up and improve efficiency on a larger projects or programs.

Devolites, Jennifer L.↗
NASA NTRS2005

MER : from landing to six wheels on Mars ... twice

Application of the Pathfinder landing system design to enclose the much larger Mars Exploration Rover required a variety of Rover deployments to achieve the surface driving configuration. The project schedule demanded that software design, engineering model test, and flight hardware build to be accomplished in parallel. This challenge was met through (a) bounding unknown environments against which to design and test, (b) early mechanical prototype testing, (c) constraining the scope of on-board autonomy to survival-critical deployments, (d) executing a balance of nominal and off-nominal test cases, (e) developing off-nominal event mitigation techniques before landing, (f) flexible replanning in response to surprises during operations. Here is discussed several specific events encountered during initial MER surface operations.

Mars Exploration Rover (MER)↗
NASA NTRS1973

The Viking Mission

The Viking Mission is a scientific exploration of the planet Mars with particular emphasis on the search for life. Two unmanned spacecraft will be launched from Cape Kennedy in 1975 and will arrive at Mars in the summer of 1976. Each spacecraft will consist of an orbiter and lander. The landing sites will be preselected before launch and certified by orbital reconnaissance before landing. Soft landing on the surface will be accomplished by decelerating first on an aeroshell, then a deployed parachute and finally using terminal propulsion engines. Thirteen investigations will be performed, including mapping experiments from the orbiter, and analytical experiments on the surface which deal broadly with the biology, geosciences and atmospheric characteristics of the planet.

Martin, J. S., Jr.↗
NASA NTRS1973

Mars exploration with Viking

The Viking Mission is a scientific exploration of the planet Mars with particular emphasis on the search for life. Two unmanned spacecraft will be launched from Cape Kennedy in 1975 and will arrive at Mars in the summer of 1976. Each spacecraft will consist of an orbiter and lander. The landing sites will be preselected before launch and certified by orbital reconnaissance before landing. Soft landing on the surface will be accomplished by decelerating first on an aeroshell, then a deployed parachute and finally using terminal propulsion engines. Thirteen investigations will be performed, including mapping experiments from the orbiter, and analytical experiments on the surface which deal broadly with the biology, geosciences and atmospheric characteristics of the planet.

Martin, J. S., Jr.↗
NASA NTRS1974

Calculation of the longitudinal aerodynamic characteristics of STOL aircraft with externally-blown jet-augmented flaps

A theoretical investigation was made to develop methods for predicting the longitudinal aerodynamic characteristics of externally-blown, jet-augmented wing-flap combinations. A potential flow analysis was used to develop two models: a wing-flap lifting surface model and a high-bypass-ratio turbofan engine wake model. Use of these two models in sequence provides for calculation of the wing-flap load distribution including the influence of the engine wake. The method can accommodate multiple engines per wing panel and part-span flaps but is limited to the case where the flow and geometry of the configuration are symmetric about a vertical plane containing the wing root chord. Comparisons of predicted and measured lift and pitching moment on unswept and swept wings with one and two engines per panel and with various flap deflection angles indicate satisfactory prediction of lift and moment for flap deflections up to 30 to 40 degrees. At higher flap angles with and without power, the method begins to overpredict lift, due probably to the appearance of flow separation on the flaps.

Dillenius, M. F. E.↗
NASA NTRS1975

Apollo program soil mechanics experiment

The soil mechanics investigation was conducted to obtain information relating to the landing interaction of the lunar module (LM) with the lunar surface, and lunar soil erosion caused by the spacecraft engine exhaust. Results obtained by study of LM landing performance on each Apollo mission are summarized.

Scott, R. F.↗
NASA NTRS1975

Fluctuating pressures on aircraft wing and flap surfaces associated with powered-lift systems

The present work presents results from two research studies that provide information on the fluctuating pressures generated by the use of powered-lift systems in STOL aircraft. Data are given for several chordwise and spanwise locations on large-scale models of an externally blown flap (EBF) configuration and an upper surface blown flap (USB) configuration in which actual jet engines were used. Pressure levels were high enough to indicate that special design effort will be required to avoid acoustic fatigue failures of wing and flap sturctures. The observation that pressure levels did not decrease very much with increased distance from the engine exhaust center line suggests that a STOL aircraft fuselage, which is in relatively close proximity to the engines for aerodynamic reasons, will be subjected to unusually high external overall fluctuating pressure levels (OAFPLs) that may cause difficulty in control of the cabin noise level.

Mixson, J. S.↗
NASA NTRS1975

Fluctuating surface pressure measurements on USB wing using two types of transducers

Measurements of the fluctuating pressures on the wing surface of an upper-surface-blown powered-lift model and a JT15 engine were obtained using two types of pressure transducers. The pressures were measured using overall-fluctuating pressures and power spectral density analyses for various thrust settings and two jet impingement angles. Comparison of the data from the two transducers indicate that similar results are obtained in the lower frequency ranges for both transducers. The data also indicate that for this configuration, the highest pressure levels occur at frequencies below 2000 Hz.

Reed, J. B.↗
NASA NTRS1978

Flight test techniques for low speed airfoil evaluation

Techniques for in-flight evaluation of new airfoils by modifying a single engine general aviation aircraft and measuring and recording airfoil surface pressures, airfoil wake pressures, and aircraft angle of attack and airspeed are presented. Included are descriptions of the aircraft modifications, instrumentation, data reduction techniques, illustrations of typical results and comments on new equipment for flight test applications.

Hoffmann, M. J.↗
NASA NTRS1981

Extinguishing in-flight engine fuel-leak fires with dry chemicals

The fire extinguishant storage temperature requirements were examined for several commercially available dry chemicals. Particular emphasis was placed on the development of dry powder extinguishant that, when discharged into a jet engine fuel leak fire, would stick to the hot surfaces. Moreover, after putting out the initial fire, these extinguishants would act as antireignition catalysts, even when the fuel continued to leak onto the heated surface.

Altman, R. L.↗
NASA NTRS1986

Plasma interactions and surface/material effects

A discussion on plasma interactions and surface/material effects is summarized. The key issues in this area were: (1) the lack of data on the material properties of common spacecraft surface materials; (2) lack of understanding of the contamination and decontamination processes; and (3) insufficient analytical tools to model synergistic phenomena related to plasma interactions. Without an adequate database of material properties, accurate system performance predictions cannot be made. The interdisciplinary nature of the surface-plasma interactions area makes it difficult to plan and maintain a coherent theoretical and experimental program. The shuttle glow phenomenon is an excellent example of an unanticipated, complex interaction involving synergism between surface and plasma effects. Building an adequate technology base for understanding and predicting surface-plasma interactions will require the coordinated efforts of engineers, chemists, and physicists. An interdisciplinary R and D program should be organized to deal with similar problems that the space systems of the 21st century may encounter.

Mandel, M.↗