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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 829 records · Page 46

Cluster Development Test 2: An Assessment of a Failed Test

On 31 July 2008 the National Aeronautics and Space Administration Crew Exploration Vehicle Parachute Assembly System team conducted the final planned cluster test of the first generation parachute recovery system design. The two primary test objectives were to demonstrate the operation of the complete parachute system deployed from a full scale capsule simulator and to demonstrate the test technique of separating the capsule simulator from the Low Velocity Air Drop pallet used to extract the test article from a United States Air Force C-17 aircraft. The capsule simulator was the Parachute Test Vehicle with an accurate heat shield outer mold line and forward bay compartment of the Crew Exploration Vehicle Command Module. The Parachute Test Vehicle separated cleanly from the pallet following extraction, but failed to reach test conditions resulting in the failure of the test and the loss of the test assets. No personnel were injured. This paper will discuss the design of the test and the findings of the team that investigated the test, including a discussion of what were determined to be the root causes of the failure.

Machin, Ricardo A.↗

Post-Launch Calibration and Testing of Space Weather Instruments on GOES-R Satellite

The Geostationary Operational Environmental Satellite - R (GOES-R) is the first of a series of satellites to be launched, with the first launch scheduled for October 2016. The three instruments - Solar Ultra Violet Imager (SUVI), Extreme ultraviolet and X-ray Irradiance Sensor (EXIS), and Space Environment In-Situ Suite (SEISS) provide the data needed as inputs for the product updates National Oceanic and Atmospheric Administration (NOAA) provides to the public. SUVI is a full-disk extreme ultraviolet imager enabling Active Region characterization, filament eruption, and flare detection. EXIS provides inputs to solar backgrounds/events impacting climate models. SEISS provides particle measurements over a wide energy-and-flux range that varies by several orders of magnitude and these data enable updates to spacecraft charge models for electrostatic discharge. EXIS and SEISS have been tested and calibrated end-to-end in ground test facilities around the United States. Due to the complexity of the SUVI design, data from component tests were used in a model to predict on-orbit performance. The ground tests and model updates provided inputs for designing the on-orbit calibration tests. A series of such tests have been planned for the Post-Launch Testing (PLT) of each of these instruments, and specific parameters have been identified that will be updated in the Ground Processing Algorithms, on-orbit parameter tables, or both. Some of SUVI and EXIS calibrations require slewing them off the Sun, while no such maneuvers are needed for SEISS. After a six-month PLT period the GOES-R is expected to be operational. The calibration details are presented in this paper.

On-orbit Calibration↗

Post-Launch Calibration and Testing of Space Weather Instruments on GOES-R Satellite

The Geostationary Operational Environmental Satellite - R (GOES-R) is the first of a series of satellites to be launched, with the first launch scheduled for October 2016. The three instruments Solar UltraViolet Imager (SUVI), Extreme ultraviolet and X-ray Irradiance Sensor (EXIS), and Space Environment In-Situ Suite (SEISS) provide the data needed as inputs for the product updates National Oceanic and Atmospheric Administration (NOAA) provides to the public. SUVI is a full-disk extreme ultraviolet imager enabling Active Region characterization, filament eruption, and flare detection. EXIS provides inputs to solar back-ground-sevents impacting climate models. SEISS provides particle measurements over a wide energy-and-flux range that varies by several orders of magnitude and these data enable updates to spacecraft charge models for electrostatic discharge. EXIS and SEISS have been tested and calibrated end-to-end in ground test facilities around the United States. Due to the complexity of the SUVI design, data from component tests were used in a model to predict on-orbit performance. The ground tests and model updates provided inputs for designing the on-orbit calibration tests. A series of such tests have been planned for the Post-Launch Testing (PLT) of each of these instruments, and specific parameters have been identified that will be updated in the Ground Processing Algorithms, on-orbit parameter tables, or both. Some of SUVI and EXIS calibrations require slewing them off the Sun, while no such maneuvers are needed for SEISS. After a six-month PLT period the GOES-R is expected to be operational. The calibration details are presented in this paper.

On-orbit Calibration↗

Helicopter /RSRA/ in-flight escape system - Component qualification

The paper describes the design, development, and qualification approach for the RSRA (Rotor Systems Research Aircraft) system explosive and pyrotechnic components. The approach was based on previous experience and included: (1) the application of good design practice and quality control, (2) a thorough examination of component interfaces through demonstration testing of functional margins, (3) the carrying out of thorough real-world sequential environmental testing, and (4) the operation of environmentally exposed units in subsystem-level tests at temperature, force, and energy limits. Owing largely to this approach, the RSRA became the first helicopter system to contain a fully qualified and operational in-flight escape system.

Bement, L. J.↗

Evaluation of Emergency-Locator-Transmitter performance in real and simulated crash tests

Emergency locator transmitter (ELT) activation problems were investigated by testing a sampling of ELT units in actual crashes and in a special test apparatus which simulated longitudinal crash pulses with superimposed local structural resonances. The probable causes of excessive false alarms and nonactivation of ELT's during crash situations were determined. Solutions to operational and technical problems were also examined as well as the sensitivity of ELT impact switches to orientation and to local structural vibrations.

Carden, H. D.↗

Control structural interaction testbed: A model for multiple flexible body verification

Conventional end-to-end ground tests for verification of control system performance become increasingly complicated with the development of large, multiple flexible body spacecraft structures. The expense of accurately reproducing the on-orbit dynamic environment and the attendant difficulties in reducing and accounting for ground test effects limits the value of these tests. TRW has developed a building block approach whereby a combination of analysis, simulation, and test has replaced end-to-end performance verification by ground test. Tests are performed at the component, subsystem, and system level on engineering testbeds. These tests are aimed at authenticating models to be used in end-to-end performance verification simulations: component and subassembly engineering tests and analyses establish models and critical parameters, unit level engineering and acceptance tests refine models, and subsystem level tests confirm the models' overall behavior. The Precision Control of Agile Spacecraft (PCAS) project has developed a control structural interaction testbed with a multibody flexible structure to investigate new methods of precision control. This testbed is a model for TRW's approach to verifying control system performance. This approach has several advantages: (1) no allocation for test measurement errors is required, increasing flight hardware design allocations; (2) the approach permits greater latitude in investigating off-nominal conditions and parametric sensitivities; and (3) the simulation approach is cost effective, because the investment is in understanding the root behavior of the flight hardware and not in the ground test equipment and environment.

Chory, M. A.↗

Aircraft cabin water spray disbenefits study

The concept of utilizing a cabin water spray system (CWSS) as a means of increasing passenger evacuation and survival time following an accident has received considerable publicity and has been the subject of testing by the regulatory agencies in both the United States and Europe. A test program, initiated by the CAA in 1987, involved the regulatory bodies in both Europe and North America in a collaborative research effort to determine the benefits and 'disbenefits' (disadvantages) of a CWSS. In order to obtain a balanced opinion of an onboard CWSS, NASA, and FAA requested the Boeing Commercial Airplane Group to investigate the potential 'disbenefits' of the proposed system from the perspective of the manufacturer and an operator. This report is the result of a year-long, cost-sharing contract study between the Boeing Commercial Airplane Group, NASA, and FAA. Delta Air Lines participated as a subcontract study team member and investigated the 'return to service' costs for an aircraft that would experience an uncommanded operation of a CWSS without the presence of fire. Disbenefits identified include potential delays in evacuation, introduction of 'common cause failure' in redundant safety of flight systems, physiological problems for passengers, high cost of refurbishment for inadvertent discharge, and potential to negatively affect other safety systems.

Reynolds, Thomas L.↗

BSA Delta Qualification 2, volume 3, book 1

This report, presented in three volumes, provides the results of a two-motor Delta Qualification 2 program conducted in 1993 to certify the following enhancements for incorporation into booster separation motor (BSM) flight hardware: vulcanized-in-place nozzle aft closure insulation; new iso-static ATJ bulk graphite throat insert material; adhesive EA 9394 for bonding the nozzle throat, igniter grain rod/centering insert/igniter case; deletion of the igniter adapter insulator ring; deletion of the igniter adapter/igniter case interface RTV; and deletion of Loctite from igniter retainer plate threads. The enhancements above directly resulted from (1) the BSM total quality management (TQM) team initiatives to enhance the BSM producibility, and (2) the necessity to qualify new throat insert and adhesive systems to replace existing materials that will not be available. Testing was completed at both the component and motor levels. Component testing was accomplished to screen candidate materials (e.g., throat materials, adhesive systems) and to optimize processes (e.g., aft closure insulator vulcanization approach) prior to their incorporation into the test motors. Motor tests -- consisting of two motors, randomly selected by USBI's on-site quality personnel from production lot AAY, which were modified to accept the enhancements -- were completed to provide the final qualification of the enhancements for incorporation into flight hardware. Volume 3 book 1 provides supporting documentation to the analyses and plans of testing the two Delta Qualification units including thermal cycling planning/data acceptance records, environmental test procedures and pretest temperature conditioning history, Delta Qualification test plan, and specification SE0837 -- mix acceptance test specification.

Source record↗

Humidifier Development and Applicability to the Next Generation Portable Life Support System

A development effort at the NASA Johnson Space Center investigated technologies to determine whether a humidifier would be required in the Portable Life Support System (PLSS) envisioned for future exploration missions. The humidifier has been included in the baseline PLSS schematic since performance testing of the Rapid Cycle Amine (RCA) indicates that the RCA over-dries the ventilation gas stream. Performance tests of a developmental humidifier unit and commercial off-the-shelf (COTS) units were conducted in December 2009. Following these tests, NASA revisited the need for a humidifier via system analysis. Results of this investigation indicate that it is feasible to meet humidity requirements without the humidifier if other changes are made to the PLSS ventilation loop and the Liquid Cooling and Ventilation Garment (LCVG).

Conger, Bruce↗

Humidifier Development and Applicability to the Next Generation Portable Life Support System

A development effort at the NASA Johnson Space Center investigated technologies to determine whether a humidifier would be required in the Portable Life Support System (PLSS) envisioned for future exploration missions. The humidifier has been included in the baseline PLSS schematic since performance testing of the Rapid Cycle Amine (RCA) indicates that the RCA over-dries the ventilation gas stream. Performance tests of a developmental humidifier unit and commercial off-the-shelf (COTS) units were conducted in December 2009. Following these tests, NASA revisited the need for a humidifier via system analysis. Results of this investigation indicate that it is feasible to meet humidity requirements without the humidifier if other changes are made to the PLSS ventilation loop and the Liquid Cooling and Ventilation Garment (LCVG).

Conger, Bruce C.↗

HERO CarbonSAFE Phase 2 Project in the Columbia River Basalt Group

The Hermiston, Oregon Basalt CarbonSAFE Phase II project (HERO CarbonSAFE) seeks to accelerate the deployment of commercial carbon dioxide (CO2) storage projects in basaltic rocks. Basalt CO2 storage has several advantages to conventional saline storage reservoirs including 1. The potential for rapid mineralization of CO2, 2. Associated decreases in pressure and CO2 migration risks, 3. Reduced long-term monitoring requirements with respect to plume tracking, 4. Widespread geographic distribution and, 5. Large storage potential due to thickness, porosity, and CO2 interactions with basalt. And for locations such as the Pacific Northwest, Hawaii, Iceland, India and Japan, basalts may offer the only economically feasible option for local CO2 storage. However, there are limited field-scale assessments of CO2 storage in basalt, and current carbon capture utilization and storage (CCUS) permitting and regulatory frameworks were developed for conventional saline reservoirs. HERO CarbonSAFE is designed to address research gaps and uncertainties associated with basalt storage. Specifically, the project will assess the feasibility of CO2 injection in the deep layered basalts, long-term storage (mineralization), practical approaches for large-scale implementation (50+ million metric tons of CO2 over 30 years), lithology-specific risks, and the technoeconomic potential for CO2 storage in basalts. The HERO CarbonSAFE project will assess feasibility of developing a commercial-scale (50+ million metric tons of CO2) geological storage complex within the Columbia River Basalt Group (CRBG), a layered continental flood basalt complex that underlies Calpine’s natural gas-fired Hermiston Power Project (HPP) in Hermiston, OR (Figure 1). Under this 2-year CarbonSAFE Phase II project, the HERO team will conduct a data acquisition campaign that includes drilling a stratigraphic well to a total depth of ~1,500 m into the thick layered basalts proximal to HPP. A comprehensive well logging and hydrologic testing program will be augmented with new core collected from flow zones and sealing units, and comprehensive laboratory testing to help refine the kinetic rates of mineralization. The newly acquired information will be integrated with existing data from regional wells to correlate basalt injection zone properties to develop storage hub/commercial-scale models. Using these models, the project team will evaluate injection scenarios to define the technical and economic potential for storing a minimum of 50 million metric tons of CO2 over a 30-year period, along with a robust sensitivity analysis on key parameters governing reservoir viability for sustainable injection over a commercial project lifetime. Specific technical objectives of HERO are: (1) assessing the reservoir response of a series of stacked layered reservoir flowtop sequences occurring in this area of the CRBG to commercial-scale injection volumes; (2) extending prior efforts by the project team to characterize the deep layered basalts encountered in regional studies, to leverage prior investments by U.S. Department of Energy’s (DOE) Carbon Storage program; (3) leveraging DOE’s mineralization characterization efforts to advance model parametrization for commercial scale injection of CO2 in basalts; (4) conducting risk assessments associated with scaling up to commercial storage hub injection goals, while validating DOE’s National Risk Assessment Partnership (NRAP) tools, to identify potential constraints that would prevent the CRBG from serving as a commercial-scale storage complex; (5) developing mitigation plans to address identified risks; (6) developing a commercial-scale injection and monitoring, verification and accounting (MVA) strategy; (7) utilizing computational models to define and minimize, if possible, the Area of Review (AoR) under Class VI regulations; and (8) developing a robust CO2 management strategy for CRBG that also considers a regional source/sink approach that is responsive to stakeholder needs and industrial demand. Specific institutional objectives are: (1) identifying and developing plans to mitigate the nontechnical challenges associated with the build-out of a commercial-scale storage complex within the CRBG with integrated CO2 sources; (2) implementing the community outreach plan; (3) conducting regulatory research, including a survey of issues related to pore space ownership, MVA and long-term assurance of mineralization-based storage, to support an eventual application for a UIC Class VI permit; (4) advancing the project’s plan for CO2 liability management; and (5) continuing to refine and update the project’s economic model. The final objective is the preparation of a comprehensive Site Characterization Plan that draws upon the technical and institutional feasibility assessments to prepare the project for future commercialization efforts.

58 GEOSCIENCES↗

High power ferrite microwave switch

A high power ferrite microwave switch was developed along with associated electronic driver circuits for operation in a spaceborne high power microwave transmitter in geostationary orbit. Three units were built and tested in a space environment to demonstrate conformance to the required performance characteristics. Each unit consisted of an input magic-tee hybrid, two non-reciprocal latching ferrite phase shifters, an out short-slot 3 db quadrature coupler, a dual driver electronic circuit, and input logic interface circuitry. The basic mode of operation of the high power ferrite microwave switch is identical to that of a four-port, differential phase shift, switchable circulator. By appropriately designing the phase shifters and electronic driver circuits to operate in the flux-transfer magnetization mode, power and temperature insensitive operation was achieved. A list of the realized characteristics of the developed units is given.

Bardash, I.↗

Space power application of the all purpose mini-Brayton rotating unit /mini-BRU/

The design of and results of tests on the mini-Brayton rotating unit (mini-BRU) are presented. Results demonstrate the flat performance trends of the mini-BRU system. The system is 'all-purpose'; it is essentially a closed Brayton cycle engine. A power spectrum comprised between 2.1 and 1.4 kWe and recuperator sizes of 106 or 75 lbs are envisioned for the final in-use configuration.

Gable, R. D.↗

Built-In Diagnostics (BID) Of Equipment/Systems

Diagnostician(TM)-on-Chip (DOC) technology identifies faults and commands systems reconfiguration. Smart microcontrollers operating in conjunction with other system-control circuits, command self-correcting system/equipment actions in real time. DOC microcontroller generates commands for associated built-in test equipment to stimulate unit of equipment diagnosed, collects and processes response data obtained by built-in test equipment, and performs diagnostic reasoning on response data, using diagnostic knowledge base derived from design data.

Granieri, Michael N.↗

Development of a PPT for the EO-1 Spacecraft

A Pulsed Plasma Thruster (PPT) has been developed for use in a technology demonstration flight experiment on the Earth Observing 1 (EO-1) New Millennium Program mission. The thruster replaces the spacecraft pitch axis momentum wheel for control and momentum management during an experiment of a minimum three-day duration. The EO-1 PPT configuration is a combination of new technology and design heritage from similar systems flown in the 1970's and 1980's. Acceptance testing of the protoflight unit has validated readiness for flight, and integration with the spacecraft, including initial combined testing, has been completed. The thruster provides a range of capability from 90 microN-sec impulse bit at 650 sec specific impulse for 12 W input power, through 860 microN-sec impulse bit at 1400 see specific impulse for 70 W input power. Development of this thruster reinitiates technology research and development and re-establishes an industry base for production of flight hardware. This paper reviews the EO-1 PPT development, including technology selection, design and fabrication, acceptance testing, and initial spacecraft integration and test.

Benson, Scott W.↗

RESOLVE Projects: Lunar Water Resource Demonstration and Regolith Volatile Characterization

To sustain affordable human and robotic space exploration, the ability to live off the land at the exploration site will be essential. NASA calls this ability in situ resource utilization (ISRU) and is focusing on finding ways to sustain missions first on the Moon and then on Mars. The ISRU project aims to develop capabilities to technology readiness level 6 for the Robotic Lunar Exploration Program and early human missions returning to the Moon. NASA is concentrating on three primary areas of ISRU: (1) excavating, handling, and moving lunar regolith, (2) extracting oxygen from lunar regolith, and (3) finding, characterizing, extracting, separating, and storing volatile lunar resources, especially in the permanently shadowed polar craters. To meet the challenges related to technology development for these three primary focus areas, the Regolith and Environment Science and Oxygen and Lunar Volatile Extraction (RESOLVE) project was initiated in February 2005, through funding by the Exploration Systems Mission Directorate. RESOLVE's objectives are to develop requirements and conceptual designs and to perform breadboard concept verification testing of each experiment module. The final goal is to deliver a flight prototype unit that has been tested in a relevant lunar polar environment. Here we report progress toward the third primary area creating ways to find, characterize, extract, separate, and store volatile lunar resources. The tasks include studying thermal, chemical, and electrical ways to collect such volatile resources as hydrogen, water, nitrogen, methane, and ammonia. We approached this effort through two subtasks: lunar water resource demonstration (LWRD) and regolith volatile characterization (RVC).

Source record↗