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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 NTRS1987

Holographic interferometry at Wright Aeronautical Laboratories

The optical diagnostics requirements and plans for the Aero Propulsion Lab. are described. This laboratory is performing work in combustion as related to aero propulsion systems. They would like to use holography and other types of optical instrumentation for combustion diagnostics and flow visualization. A movie of a laser light sheet flow visualization of a combustor in operation was shown. This movie showed extremely clear examples of vortical and unsteady flow, and it would be of interest to use image analysis to quantify such data.

Roquemore, Mel↗
NASA NTRS1987

Controlled ecological life support systems: Development of a plant growth module

An effort was made to begin defining the scientific and technical requirements for the design and construction of a ground-based plant growth facility. In particular, science design criteria for the Plant Growth Module (PGM) of the Controlled Ecological Life Support System (CELSS) were determined in the following areas: (1) irradiation parameters and associated equipment affecting plant growth; (2) air flow; (3) planting, culture, and harvest techniques; (4) carbon dioxide; (5) temperature and relative humidity; (6) oxygen; (7) construction materials and access; (8) volatile compounds; (9) bacteria, sterilization, and filtration; (10) nutrient application systems; (11) nutrient monitoring; and (12) nutrient pH and conductivity.

Averner, Mel M.↗
NASA NTRS1988

TABLET: The personal computer of the year 2000

The University of Illinois design of the TABLET portable computer extends the freedom of pen and notepad with a machine that draws on the projected power of 21st century technology. Without assuming any new, major technological breakthroughs, it seeks to balance the promises of today's growing technologies with the changing role of computers in tomorrow's education, research, security, and commerce. It seeks to gather together in one basket the matured fruits of such buzzword technologies as LCD, GPS, CCD, WSI, and DSP. The design is simple, yet sleek. Roughly the size and weight of a notebook, the machine is a dark, featureless monolith with no moving parts. Through magneto-optics, a simple LaserCard provides exchangeable, mass data storage. Its I/O surface, in concert with built-in infrared and cellular transceivers, puts the user in touch with anyone and anything. The ensemble of these components, directed by software that can transform it into anything from a keyboard or notepad to an office or video studio, suggests an instrument of tremendous power and freedom.

Mel, Bartlett W.↗
NASA NTRS1989

Conceptual design of a closed loop nutrient solution delivery system for CELSS implementation in a micro-gravity environment

This paper describes the results of a study to develop a conceptual design for an experimental, closed-loop fluid handling system capable of monitoring, controlling, and supplying nutrient solution to higher plants. The Plant Feeder Experiment (PFX) is designed to be flight tested in a micro-gravity (micro-g) environment and was developed under NASA's In-Space Technology Experiments Program (INSTEP). When flown, PFX will provide information on both the generic problems of micro-g fluid handling and the specific problems associated with the delivery of nutrient solution in a micro-g environment. The experimental hardware is designed to fit into two middeck lockers on the Space Shuttle, and incorporates several components that have previously been flight tested.

Schwartzkopf, Steven H.↗
NASA NTRS1990

Conceptual design of a closed loop nutrient solution delivery system for CELSS implementation in a micro-gravity environment

Described here are the results of a study to develop a conceptual design for an experimental closed loop fluid handling system capable of monitoring, controlling, and supplying nutrient solution to higher plants. The Plant Feeder Experiment (PFE) is designed to be flight tested in a microgravity environment. When flown, the PFX will provide information on both the generic problems of microgravity fluid handling and the specific problems associated with the delivery of the nutrient solution in a microgravity environment. The experimental hardware is designed to fit into two middeck lockers on the Space Shuttle, and incorporates several components that have previously been flight tested.

Schwartzkopf, Steven H.↗
NASA NTRS1992

Almond-Shaped Test Body

Almond shaped test body developed for use in electromagnetic anechoic chamber for evaluation of range and measurement of components has low radar cross section that varies with angle over large dynamic range. Surface is composite formed by joining properly scaled ellipsoidal surfaces. Used to mount components whose radar cross sections are to be measured, and simulate backscatter characteristics of component as though it were over infinite ground plane.

Dominek, Allen↗
NASA NTRS1992

Crab pulsar giant pulses: Simultaneous radio and GRO observations

Observations are reported of the Crab pulsar made at radio frequencies concurrent with Oriented Scintillation Spectrometer Experiment (OSSE) observations from 15 to 27 May 1991. Using the 43 m telescope at Green Bank at 0.8 and 1.4 GHz, samples were made continuously for 10 hrs/day at intervals of 100 to 300 microsecs. The analysis of the radio data includes calculation of histograms of pulse intensities, absolute timing to about 20 microsec precision, and characterization of intensity variations on time scales from the 33 ms spin period to days. The most detailed analysis is presented made of giant pulses. The ultimate goal is to bin the radio data into giant and nongiant pulses and to form average waveforms of OSSE data for the corresponding pulse periods. A test is done to see whether the violet radio fluctuations (which are not seen in other radio pulsars to the same degree) are correlated with low energy gamma rays, yielding constraints on the radio coherence mechanism and the steadiness of the electron-positron outflow in the magnetosphere. Timing analysis of the radio data provides a well defined ephemeris over the specified range of epochs. The gamma ray pulse phase was predicted with an error of less than 70 microsecs.

Lundgren, Scott C.↗
NASA NTRS1991

Bioregenerative life support - The initial CELSS reference configuration

The next major step in the development of an operational Controlled Ecological Life-Support System (CELSS) is the creation of a human-rated ground-based demonstrator able to constitute a CELSS's proof-of-concept. The reference configuration recently devised for such a ground facility by NASA will furnish a common reference to all investigators in the field, thereby facilitating performance comparisons among candidate subsystems and clarifying system-level modeling. A detailed NASA reference CELSS flowcharting is presented.

Rummel, John D.↗
NASA NTRS1992

Design and performance of a Cryogenic Heat Pipe Experiment (CRYOHP)

The Cryogenic Heat Pipe Experiment which is designed to demonstrate the thermal performance of two different axially grooved oxygen heat pipes in microgravity is discussed. The CRYOHP is manifested for flight aboard STS-53. The first heat pipe design is based on an extrapolated 0-g transport capability of about 20 W-m with oxygen in the range of 80-100 K. The second heat pipe design permits 0-g 'dry-out' in the CRYOHP and offers improved ground testability for 1-g correlation.

Beam, Jerry↗
NASA NTRS1990

The MODE family of on-orbit experiments: The Middeck Active Control Experiment (MACE)

A flight experiment entitled the Middeck Active Control Experiment (MACE), proposed by the Space Engineering Research Center (SERC) at the Massachusetts Institute of Technology, is described. This is the second in a family of flight experiments being developed at MIT. The first is the Middeck 0-Gravity Dynamics Experiment (MODE) which investigates the nonlinear behavior of contained fluids and truss structures in zero gravity. The objective of the MACE program is to investigate and validate the modeling of the dynamics of an actively controlled flexible, articulating, multibody platform free floating in zero gravity. A rationale and experimental approach for the program are presented. The rationale shows that on-orbit testing, coupled with ground testing and a strong analytical program, is necessary in order to fully understand both how flexibility of the platform affects the pointing problem, as well as how gravity perturbs this structural flexibility causing deviations between 1- and 0-gravity behavior. The experimental approach captures the essential physics of multibody platforms, by identifying the appropriate attributes, tests, and performance metrics of the test article and defines the tests required to successfully validate the analytical framework.

Crawley, Edward F.↗
NASA NTRS1993

Engine management during NTRE start up

The topics are presented in viewgraph form and include the following: total engine system management critical to successful nuclear thermal rocket engine (NTRE) start up; NERVA type engine start windows; reactor power control; heterogeneous reactor cooling; propellant feed system dynamics; integrated NTRE start sequence; moderator cooling loop and efficient NTRE starting; analytical simulation and low risk engine development; accurate simulation through dynamic coupling of physical processes; and integrated NTRE and mission performance.

Bulman, Mel↗
NASA NTRS1993

Long-slit ultraviolet spectroscopy of Comet Austin (1990 V)

The spatial distributions of the brightest features in the far-UV spectrum of Comet Austin were measured, and it is found that they are generally similar to those found for Comet Halley during two rocket observations in 1986. As in Halley, the CO profile can be fit to a radial outflow profile for a source whose size is smaller than the instrumental spatial resolution. Neither the shape nor the magnitude of the extended atomic carbon profiles, however, can be satisfactorily explained by the photodissociation of CO. No evidence is found for an extended source of CO in the coma; thus, suggestions that the additional carbon can come directly from grains are difficult to accept since Austin is a low-dust comet. The presence of the O I 1356 A feature implies that there is a photoelectron excitation source in the coma. The measured O I 1304 A distribution is consistent with H2O being the dominant source of oxygen in the coma. The atomic sulfur profile matches that expected for a daughter product of relatively short-lived parents.

Sahnow, David J.↗
NASA NTRS1993

Evolving directions in NASA's planetary rover requirements and technology

This paper reviews the evolution of NASA's planning for planetary rovers (i.e. robotic vehicles which may be deployed on planetary bodies for exploration, science analysis, and construction) and some of the technology that has been developed to achieve the desired capabilities. The program is comprised of a variety of vehicle sizes and types in order to accommodate a range of potential user needs. This includes vehicles whose weight spans a few kilograms to several thousand kilograms; whose locomotion is implemented using wheels, tracks, and legs; and whose payloads vary from microinstruments to large scale assemblies for construction. We first describe robotic vehicles, and their associated control systems, developed by NASA in the late 1980's as part of a proposed Mars Rover Sample Return (MRSR) mission. Suggested goals at that time for such an MRSR mission included navigating for one to two years across hundreds of kilometers of Martian surface; traversing a diversity of rugged, unknown terrain; collecting and analyzing a variety of samples; and bringing back selected samples to the lander for return to Earth. Subsequently, we present the current plans (considerably more modest) which have evolved both from technological 'lessons learned' in the previous period, and modified aspirations of NASA missions. This paper describes some of the demonstrated capabilities of the developed machines and the technologies which made these capabilities possible.

Weisbin, C. R.↗
NASA NTRS1993

Evolving directions in NASA's planetary rover requirements and technology

The evolution of NASA's planning for planetary rovers (that is robotic vehicles which may be deployed on planetary bodies for exploration, science analysis, and construction) and some of the technology that was developed to achieve the desired capabilities is reviewed. The program is comprised of a variety of vehicle sizes and types in order to accommodate a range of potential user needs. This includes vehicles whose weight spans a few kilograms to several thousand kilograms; whose locomotion is implemented using wheels, tracks, and legs; and whose payloads vary from microinstruments to large scale assemblies for construction. Robotic vehicles and their associated control systems, developed in the late 1980's as part of a proposed Mars Rover Sample Return (MRSR) mission, are described. Goals suggested at the time for such a MRSR mission included navigating for one to two years across hundreds of kilometers of Martian surface; traversing a diversity of rugged, unknown terrain; collecting and analyzing a variety of samples; and bringing back selected samples to the lander for return to Earth. Current plans (considerably more modest) which have evolved both from technological 'lessons learned' in the previous period, and modified aspirations of NASA missions are presented. Some of the demonstrated capabilities of the developed machines and the technologies which made these capabilities possible are described.

Weisbin, C. R.↗
NASA NTRS1994

A Revolutionary Lunar Space Transportation System Architecture Using Extraterrestrial Lox-augmented NTR Propulsion

The concept of a liquid oxygen (LOX)-augmented nuclear thermal rocket (NTR) engine is introduced, and its potential for revolutionizing lunar space transportation system (LTS) performance using extraterrestrial 'lunar-derived' liquid oxygen (LUNOX) is outlined. The LOX-augmented NTR (LANTR) represents the marriage of conventional liquid hydrogen (LH2)-cooled NTR and airbreathing engine technologies. The large divergent section of the NTR nozzle functions as an 'afterburner' into which oxygen is injected and supersonically combusted with nuclear preheated hydrogen emerging from the NTR's choked sonic throat: 'scramjet propulsion in reverse.' By varying the oxygen-to-fuel mixture ratio (MR), the LANTR concept can provide variable thrust and specific impulse (Isp) capability with a LH2-cooled NTR operating at relatively constant power output. For example, at a MR = 3, the thrust per engine can be increased by a factor of 2.75 while the Isp decreases by only 30 percent. With this thrust augmentation option, smaller, 'easier to develop' NTR's become more acceptable from a mission performance standpoint (e.g., earth escape gravity losses are reduced and perigee propulsion requirements are eliminated). Hydrogen mass and volume is also reduced resulting in smaller space vehicles. An evolutionary NTR-based lunar architecture requiring only Shuttle C and/or 'in-line' shuttle-derived launch vehicles (SDV's) would operate initially in an 'expandable mode' with NTR lunar transfer vehicles (LTV's) delivering 80 percent more payload on piloted missions than their LOX/LH2 chemical propulsion counterparts. With the establishment of LUNOX production facilities on the lunar surface and 'fuel/oxidizer' depot in low lunar orbit (LLO), monopropellant NTR's would be outfitted with an oxygen propellant module, feed system, and afterburner nozzle for 'bipropellant' operation. The LANTR cislunar LTV now transitions to a reusable mode with smaller vehicle and payload doubling benefits on each piloted round trip mission. As the initial lunar outposts grow to centralized bases and settlements with a substantial permanent human presence, a LANTR-powered shuttle capable of 36 to 24 hour 'one-way' trip times to the moon and back becomes possible with initial mass in low earth orbit (IMLEO) requirements of approximately 160 to 240 metric tons, respectively.

Borowski, Stanley K.↗
NASA NTRS1998

A Method for Making Cross-Comparable Estimates of the Benefits of Decision Support Technologies for Air Traffic Management

We present a general method for making cross comparable estimates of the benefits of NASA-developed decision support technologies for air traffic management, and we apply a specific implementation of the method to estimate benefits of three decision support tools (DSTs) under development in NASA's advanced Air Transportation Technologies Program: Active Final Approach Spacing Tool (A-FAST), Expedite Departure Path (EDP), and Conflict Probe and Trial Planning Tool (CPTP). The report also reviews data about the present operation of the national airspace system (NAS) to identify opportunities for DST's to reduce delays and inefficiencies.

Lee, David↗
NASA NTRS1999

Testing of the Strutjet RBCC Engine

The testing of the Strutjet Rocket-Based Combined Cycle (RBCC) engine is described in this presentation. Since 1996 Aerojet has conducted thousands of tests on its Strutjet RBCC Engine. The Strutjet is specifically designed as an RBCC engine. The tests included: (1) Inlet, (2) Rocket Checkouts, (3) Direct Connect Mach 6 and 8, and (4) Freejet M = 0, 2.4, 4.1. The modes tested include: (1) Air Augmented Rocket (AAR), (2) Ramjet (3) Scramjet (4) Scram/Rocket (5) Ascent/Rocket. The Strutjet RBCC engine has been tested across the complete airbreathing trajectory. The presentation shows the results of the tests, through diagrams, charts and pictures.

Bulman, Mel↗
NASA NTRS1999

Demonstrating the Performance Benefits of the Strutjet RBCC for Space Launch Architectures

The Rocket Based Combined Cycle (RBCC) engine synergistically combines the best elements of airbreathing and rocket propulsion to benefit a wide range of future reusable launch vehicles (RLV). Aerojet's Strutjet RBCC offers high Isp during mid-phase acceleration, and high thrust for boost and final ascent phases. The result is a relatively low gross weight vehicle that reduces thrust requirements compared with all-rocket solutions. Relative to combination propulsion systems, the integrated propulsive elements of the Strutjet reduce engine weight and complexity. This paper will summarize the results of tests demonstrating our latest hydrogen-fueled Strutjet RBCC engine performance, including inlet operability and performance over a range of conditions, sea level static and Mach 2.4 rocket thrust augmentation, ramjet and scramjet performance, combined scramjet/rocket performance at Mach 8, and ascent mode rocket performance. These tests have significantly advanced the technology readiness of the Strutjet engine and substantiate the performance benefits of RBCC engines for reusable launch vehicle applications. A companion paper provides a focus on Strutjet as a basis for advanced air and space architecture, covering hydrogen and hydrocarbon fuels and cooled structures.

Siebenhaar, Adam↗