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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 1,549 records · Page 86
All sourcesNASA NTRSDOE OSTI
NASA NTRS2000

Design, Development, And Testing of Umbilical System Mechanisms for the X-33 Advanced Technology Demonstrator

The X-33 Advanced Technology Demonstrator is an un-piloted, vertical take-off, horizontal landing spacecraft. The purpose of the X-33 program is to demonstrate technologies that will dramatically lower the cost of access to space. The rocket-powered X-33 will reach an altitude of up to 100 km and speeds between Mach 13 and 15. Fifteen flight tests are planned, beginning in 2000. Some of the key technologies demonstrated will be the linear aerospike engine, improved thermal protection systems, composite fuel tanks and reduced operational timelines. The X-33 vehicle umbilical connections provide monitoring, power, cooling, purge, and fueling capability during horizontal processing and vertical launch operations. Two "rise-off" umbilicals for the X-33 have been developed, tested, and installed. The X-33 umbilical systems mechanisms incorporate several unique design features to simplify horizontal operations and provide reliable disconnect during launch.

Littlefield, Alan C.↗
NASA NTRS2010

Gimbals Drive and Control Electronics Design, Development and Testing of the LRO High Gain Antenna and Solar Array Systems

Launched June 18, 2009 on an Atlas V rocket, NASA's Lunar Reconnaissance Orbiter (LRO) is the first step in NASA's Vision for Space Exploration program and for a human return to the Moon. The spacecraft (SC) carries a wide variety of scientific instruments and provides an extraordinary opportunity to study the lunar landscape at resolutions and over time scales never achieved before. The spacecraft systems are designed to enable achievement of LRO's mission requirements. To that end, LRO's mechanical system employed two two-axis gimbal assemblies used to drive the deployment and articulation of the Solar Array System (SAS) and the High Gain Antenna System (HGAS). This paper describes the design, development, integration, and testing of Gimbal Control Electronics (GCE) and Actuators for both the HGAS and SAS systems, as well as flight testing during the on-orbit commissioning phase and lessons learned.

Chernyakov, Boris↗
NASA NTRS1998

Hyper-X Engine Design and Ground Test Program

The Hyper-X Program, NASA's focused hypersonic technology program jointly run by NASA Langley and Dryden, is designed to move hypersonic, air-breathing vehicle technology from the laboratory environment to the flight environment, the last stage preceding prototype development. The Hyper-X research vehicle will provide the first ever opportunity to obtain data on an airframe integrated supersonic combustion ramjet propulsion system in flight, providing the first flight validation of wind tunnel, numerical and analytical methods used for design of these vehicles. A substantial portion of the integrated vehicle/engine flowpath development, engine systems verification and validation and flight test risk reduction efforts are experimentally based, including vehicle aeropropulsive force and moment database generation for flight control law development, and integrated vehicle/engine performance validation. The Mach 7 engine flowpath development tests have been completed, and effort is now shifting to engine controls, systems and performance verification and validation tests, as well as, additional flight test risk reduction tests. The engine wind tunnel tests required for these efforts range from tests of partial width engines in both small and large scramjet test facilities, to tests of the full flight engine on a vehicle simulator and tests of a complete flight vehicle in the Langley 8-Ft. High Temperature Tunnel. These tests will begin in the summer of 1998 and continue through 1999. The first flight test is planned for early 2000.

Voland, R. T.↗
NASA NTRSDate not supplied

Design, Build, and Testing of the Roman Space Telescope’s Wide Field Instrument Optical Stimulus System (SORC)

The Stimulus Of Ray Cones (SORC) is an optical stimulus system developed to verify, characterize, and calibrate the Roman Space Telescope’s (RST) Wide Field Instrument (WFI) under simulated operational conditions. SORC provides several critical test modes, the primary being point-source mode, which projects an image anywhere on the Focal Plane Assembly (FPA) detectors. This mode provides precise position knowledge of the FPA within WFI. Additional modes enable capturing WFI pupil alignment, evaluation of WFI’s selectable optical elements, and verification of focal plane fiber operation for higher-level system testing. The light source system incorporates a suite of narrowband and broadband fiber fed sources spanning the visible to near-infrared range, with options for pulsed or continuous wave illumination. SORC was designed and built at NASA’s Goddard Spaceflight Center (GSFC). Initial system-level testing occurred under ambient conditions in GSFC’s Spacecraft Systems Development and Integration Facility (SSDIF), followed by vacuum testing at operational temperatures (SORC at 214-222 K) in the Space Environment Simulator (SES). The system was then shipped to BAE Systems in Boulder, CO for post-shipment ambient and cryogenic testing before integration with WFI for two thermal vacuum test campaigns at cryogenic temperatures. This presentation will focus on design, development, and performance of SORC. Details of WFI verification and calibration using SORC, along with test results, have been published previously and will be referenced only as needed to describe SORC. The SORC ground test capability is critical to ensuring WFI meets stringent optical performance requirements, directly supporting the mission’s science objectives.

Stimulus of Ray Cones↗
NASA NTRS1975

Design and preliminary test results at Mach 5 of an axisymmetric slotted sound shield

The basic theory and sound attenuation mechanisms, the design procedures, and preliminary experimental results are presented for a small axisymmetric sound shield for supersonic wind tunnels. The shield consists of an array of small diameter rods aligned nearly parallel to the entrance flow with small gaps between the rods for boundary layer suction. Results show that at the lowest test Reynolds number (based on rod diameter) of 52,000 the noise shield reduced the test section noise by about 60 percent ( or 8 db attenuation) but no attenuation was measured for the higher range of test reynolds numbers from 73,000 to 190,000. These results are below expectations based on data reported elsewhere on a flat sound shield model. The smaller attenuation from the present tests is attributed to insufficient suction at the gaps to prevent feedback of vacuum manifold noise into the shielded test flow and to insufficient suction to prevent transition of the rod boundary layers to turbulent flow at the higher Reynolds numbers. Schlieren photographs of the flow are shown.

Beckwith, I. E.↗
NASA NTRS1979

Design, analysis, and tests of a shuttle-type heat-pipe-cooled leading edge

A one-half scale heat-pipe-cooled leading edge model was designed and fabricated to verify feasibility and performance of a full-scale Phase B shuttle orbiter design. Model performance was investigated experimentally by radiant heating and aerothermal tests and analytically by using a simple technique which predicts heat pipe start-up from the frozen state and also predicts transient and steady-state thermal behavior. Analytical results agree well with experimental results for start-up and steady-state heat pipe operation. The results indicate that variations in angle of attack and roll orientation had a negligible effect on heat pipe performance. The heat pipes effectively isothermalized the leading edge, and reduced peak temperatures to levels compatible with the use temperatures of superalloys. Results of these tests demonstrated the durability of the heat-pipe-cooled leading edge in withstanding earth-entry thermal and mechanical loads and indicate that the use of heat pipes in leading edge structures is a reliable concept for fully reusable hypersonic cruise and space transportation systems.

Camarda, C. J.↗
NASA NTRS1976

Design, building and test of one prototype and four final position sensor assemblies: Hall effect position sensors

This report covers the development of a three channel Hall effect position sensing system for the commutation of a three phase dc torquer motor. The effort consisted of the evaluation, modification and re-packaging of a commercial position sensor and the design of a target configuration unique to this application. The resulting design meets the contract requirements and, furthermore, the test results indicate not only the practicality and versatility of the design, but also that there may be higher limits of resolution and accuracy achievable.

Source record↗
NASA NTRS2014

Design, Fabrication and Test of WFIRST-AFTA GRISM Assembly

The Wide-Field Infra-Red Survey Telescope (WFIRST) is designed to perform wide-field imaging and slitless spectroscopic survey of the sky. A compound Grism assembly is selected as its slitless dispersing element. Compared to the grisms in several instruments installed on the Hubble space telescope, the challenge of this grism is the much wider Field Of View (FOV), larger dispersion, and smaller f. The image quality of the slitless spectrometer is directly related to how deep of the sky the spectrometer is able to see. This paper discusses how to use a diffractive lens surface to compensate the wavelength dependent aberration created by the grating in non-collimated space to make the spectrometer diffraction limited, as well as how to intelligently combine the two diffractive surfaces (lens and grating) to reduce the unwanted diffraction orders from the grating. The paper also discusses how to improve the diffraction efficiency of the diffractive surfaces, as well as how to align and assemble the optics.

Diffractive Optics↗
NASA NTRS2017

Design Guide for Aerodynamics Testing of Earth and Planetary Entry Vehicles in a Ballistic Range

The purpose of this manual is to aid in the design of an aerodynamics test of an earth or planetary entry capsule in a ballistic range. In this manual, much use is made of the results and experience gained in 50 years of ballistic range aerodynamics testing at the NASA Ames Research Center, and in particular, that gained in the last 27 years, while the author was working at NASA Ames. The topics treated herein include: Data to be obtained; flight data needed to design test; Reynolds number and dynamic similarity of flight trajectory and ballistic range test; capabilities of various ballistic ranges; Calculations of swerves due to average and oscillating lift and of drag-induced velocity decreases; Model and sabot design; materials, weights and stresses; Sabot separation; Launches at angle of attack and slapping with paper to produce pitch/yaw oscillations.

Test Design↗
DOE OSTI2020

An ERCOT test system for market design studies

An open source test system is developed that permits the dynamic modeling of centrally-managed wholesale power markets operating over highvoltage transmission grids. In default mode, the test system models basic operations in the Electric Reliability Council of Texas (ERCOT): namely, centrally-managed day-ahead and real-time markets operating over successive days, with congestion handled by locational marginal pricing. These basic operational features characterize all seven U.S. energy regions organized as centrally-managed wholesale power markets. Modeled participants include dispatchable generators, load-serving entities, and non-dispatchable generation such as unrmed wind and solar power. Users can congure a broad variety of parameters to study basic market and grid features under alternative system conditions. Users can also easily extend the test system's Java/Python software classes to study modied or newly envisioned market and grid features. Finally, the test system is integrated with a high-level simulation framework that permits it to function as a software component within larger systems, such as multi-country systems or integrated transmission and distribution systems. Finally, detailed test cases with 8-bus and 200-bus transmission grids are reported to illustrate these test system capabilities.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
NASA NTRS1974

Design development and test: Two-gas atmosphere control subsystem

An atmosphere control subsystem (ACS) was developed for NASA-IBJSC which is designed to measure the major atmospheric constituents in the manned cabin of the space shuttle orbiter and control the addition of oxygen and nitrogen to maintain the partial pressures of these gases within very close limits. The ACS includes a mass spectrometer sensor (MSS) which analyzes the atmosphere of a shuttle vehicle pressurized cabin, and an electronic control assembly (ECA). The MSS was built and tested to meet the requirements for flight equipment for the M-171 Metabolic Analyzer experiment for the Skylab flight program. The instrument analyzes an atmospheric gas sample and produces continuous 0-5 vdc analog signals proportional to the partial pressures of H2, O2, N2, H2O, CO2 and total hydrocarbons having a m/e ratio between 50 and 120. It accepts signals from the MSS proportional to the partial pressures of N2 and O2 and controls the supply of these gases to the closed cabin.

Jackson, J. K.↗
NASA NTRS1977

An advanced combustor analytical design procedure and its application in the design and development testing of a premix/prevaporized combustion system

Due to the protracted time and relatively high monetary expenditures associated with empirical design procedures, AiResearch has placed considerable emphasis on the development and use of combustor analytical models to augment the existing design techniques. A brief account of the semi-empirical design procedure is given, followed by the description of six analytical computer models. An advanced combustor design logic based upon these models is presented. A brief description of a premix/prevaporized combustion system and correlation with the models is given.

Reynolds, R. S.↗
NASA NTRS1981

Design, analysis, and test verification of advanced encapsulation systems

Thermal, optical, structural, and electrical isolation analyses are decribed. Major factors in the design of terrestrial photovoltaic modules are discussed. Mechanical defects in the different layers of an encapsulation system, it was found, would strongly influence the minimum pottant thickness required for electrical isolation. Structural, optical, and electrical properties, a literature survey indicated, are hevily influenced by the presence of moisture. These items, identified as technology voids, are discussed. Analyses were based upon a 1.2 meter square module using 10.2 cm (4-inch) square cells placed 1.3 mm apart as shown in Figure 2-2. Sizing of the structural support member of a module was determined for a uniform, normal pressure load of 50 psf, corresponding to the pressure difference generated between the front and back surface of a module by a 100 mph wind. Thermal and optical calculations were performed for a wind velocity of 1 meter/sec parallel to the ground and for module tilt (relative to the local horizontal) of 37 deg. Placement of a module in a typical array field is illustrated.

Garcia, A.↗
NASA NTRS2012

Structural Element Testing in Support of the Design of the NASA Composite Crew Module

In January 2007, the NASA Administrator and Associate Administrator for the Exploration Systems Mission Directorate chartered the NASA Engineering and Safety Center (NESC) to design, build, and test a full-scale Composite Crew Module (CCM). For the design and manufacturing of the CCM, the team adopted the building block approach where design and manufacturing risks were mitigated through manufacturing trials and structural testing at various levels of complexity. Following NASA's Structural Design Verification Requirements, a further objective was the verification of design analysis methods and the provision of design data for critical structural features. Test articles increasing in complexity from basic material characterization coupons through structural feature elements and large structural components, to full-scale structures were evaluated. This paper discusses only four elements tests three of which include joints and one that includes a tapering honeycomb core detail. For each test series included are specimen details, instrumentation, test results, a brief analysis description, test analysis correlation and conclusions.

Kellas, Sotiris↗