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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 883 records · Page 49
All sourcesNASA NTRSDOE OSTI
NASA NTRS1995

Comparative performance tests on the Mod-2, 2.5-mW wind turbine with and without vortex generators

A test program was conducted on the third Mod-2 unit at Goldendale, Washington, to systematically study the effect of vortex generators (VG's) on power performance. The subject unit was first tested without VG's to obtain baseline data. Vortex generators were then installed on the mid-blade assemblies, and the resulting 70% VG configuration was tested. Finally, vortex generators were mounted on the tip assemblies, and data was recorded for the 100% VG configuration. This test program and its results are discussed in this paper. The development of vortex generators is also presented.

Miller, G. E.↗
NASA NTRS2010

Testing to Characterize the Advanced Stirling Radioisotope Generator Engineering Unit

The Advanced Stirling Radioisotope Generator (ASRG), a high efficiency generator, is being considered for space missions. Lockheed Martin designed and fabricated an engineering unit (EU), the ASRG EU, under contract to the Department of Energy. This unit is currently undergoing extended operation testing at the NASA Glenn Research Center to generate performance data and validate life and reliability predictions for the generator and the Stirling convertors. It has also undergone performance tests to characterize generator operation while varying control parameters and system inputs. This paper summarizes and explains test results in the context of designing operating strategies for the generator during a space mission and notes expected differences between the EU performance and future generators.

Lewandowski, Edward↗
DOE OSTI2019

Statistical Sampling Considerations in Multifamily Housing

In the past 30 years, some governmental agencies and private-sector owners of multifamily housing properties have limited radon screening to partial screening (e.g., the testing of a subset of the multifamily housing dwelling units). While sampling methods have differed, most have required that if any one unit was found to be “positive,” or have radon levels ≥4 pCi/L, all remaining untested housing units would be tested (e.g. trip-wire approach).

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTAN↗
DOE OSTI2020

Effects of Riser Diameter on Solids Holdup and Particle Velocity Profiles in Circulating Fluidized Bed Riser Systems

Tests were performed in a 0.1-m diameter small circulating fluidized bed (SCFB) and 0.3 m diameter cold flow circulating fluidized bed (CFCFB) riser systems located at the National Energy Technology Laboratory (NETL) to study the effects of riser diameter on the riser hydrodynamics. These tests were performed at solids circulation rates of G s = 20 and 75 kg/m 2 s and superficial gas velocities of U g = 5.8 and 6.5 m/s using high-density polyethylene (HDPE) pellets with a density of 0.863 g/cm 3 , particle size range of 600–1400 µm (with a Sauter mean diameter of 871 µm, placing them in the Geldart B classification). Comparisons of riser axial pressure and solids fraction profiles, radial particle velocity profiles, and radial profiles of higher statistical moments and select chaos analysis parameters were considered. The results showed that for a given U g and G s , the smaller diameter riser exhibited characteristics associated with more dilute solids flow than that observed in the larger diameter riser. Additionally, the larger diameter riser exhibited a downward flow of solids near the wall under all test conditions, whereas the smaller diameter riser data exhibited little or no indications of solids downflow near the wall. Overall, these findings suggest that, from an industrial standpoint, a direct scaleup of small-scale tests cannot readily be accomplished as the solids holdup and the solids velocity profiles in small units (those normally tested in the laboratory) are not similar to those of large units and the performance of large units can therefore not be predicted from small-scale tests.

42 ENGINEERING↗
DOE OSTI2013

Corrective Action Decision Document/Closure Report for Corrective Action Unit 570: Area 9 Yucca Flat Atmospheric Test Sites, Nevada National Security Site, Nevada, Revision 0 with ROTC 1

This Corrective Action Decision Document/Closure Report presents information supporting the closure of Corrective Action Unit (CAU) 570: Area 9 Yucca Flat Atmospheric Test Sites, Nevada National Security Site, Nevada. This complies with the requirements of the Federal Facility Agreement and Consent Order (FFACO) that was agreed to by the State of Nevada; U.S. Department of Energy (DOE), Environmental Management; U.S. Department of Defense; and DOE, Legacy Management. The purpose of the CADD/CR is to provide justification and documentation supporting the recommendation that no further corrective action is needed.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2019

Closure Report for Corrective Action Unit 424: Area 3 Landfill Complex, Tonopah Test Range, Nevada, Revision 0. with ROTC 1

This Closure Report provides the documentation for closure of the Area 3 Landfill Complex Corrective Action Unit (CAU) 424. The site is located on the Tonopah Test Range, approximately 225 kilometers (140 miles) northwest of Las Vegas, Nevada. The purpose of this CR is to: Document the closure activities and provide the information collected, as recommended in the CADD. (DOE, 1998a) and proposed in the CAP (DOE~ 1998b ); Provide a Post-Closure Inspection Plan; Obtain a Notice of Completion from the NDEP; Recommend the movement of CAU 424 from Appendix III to Appendix IV of the FFACO.

54 ENVIRONMENTAL SCIENCES↗
NASA NTRS1981

Large area sheet task: Advanced Dendritic Web Growth Development

A melt level control system was implemented to provide stepless silicon feed rates from zero to rates exactly matching the silicon consumed during web growth. Bench tests of the unit were successfully completed and the system mounted in a web furnace for operational verification. Tests of long term temperature drift correction techniques were made; web width monitoring seems most appropriate for feedback purposes. A system to program the initiation of the web growth cycle was successfully tested. A low cost temperature controller was tested which functions as well as units four times as expensive.

Duncan, C. S.↗
NASA NTRS1990

Digital angular position sensor using wavelength division multiplexing

Future aircraft will use fly-by-light control systems with fiber-linked optical sensors for such measurands as temperature, pressure, and linear and angular position. A digital optical sensor is described which was developed to transmit the angular position of such slowly rotating parts as a throttle of fuel flow control valve on an aircraft. The sensor employs a reflective code plate with ten channels providing a resolution of 0.35 degrees. Two light-emitting diodes with overlapping spectra are used as light sources. A single microoptic multiplexer-demultiplexer composed of a GRIN rod lens and a miniature grating is used to disperse the spectrum and recombine the spectral components from each channel after reflection by the code plate. The results of preliminary environmental tests of this unit are discussed. The sensor has been operated for brief periods of time between -60 C and +125 without adverse effects. Preliminary vibration tests indicate that the unit will work properly at the maximum vibration levels expected in a jet-engine environment.

Fritsch, Klaus↗
NASA NTRS1998

Verification and Quantification of Single Event Effects on High Speed SRAM in Terrestrial Environments

As integrated circuits become more sensitive to charged particles and neutrons, anomalous performance due to single event effects (SEE) is a concern and requires experimental verification and quantification. The Center for Applied Radiation Research (CARR) at Prairie View A&M University has developed experiments as a participant in the NASA ER-2 Flight Program, the APEX balloon flight program and the Student Launch Program. Other high altitude and ground level experiments of interest to DoD and commercial applications are being developed. The experiment characterizes the SEE behavior of high speed and high density SRAM's. The system includes a PC-104 computer unit, an optical drive for storage, a test board with the components under test, and a latchup detection and reset unit. The test program will continuously monitor the stored checkerboard data pattern in the SW and record errors. Since both the computer and the optical drive contain integrated circuits, they are also vulnerable to radiation effects. A latchup detection unit with discrete components will monitor the test program and reset the system when necessary. The first results will be obtained from the NASA ER-2 flights, which are now planned to take place in early 1998 from Dryden Research Center in California. The series of flights, at altitudes up to 70,000 feet, and a variety of flight profiles should yield a distribution of conditions for correlating SEES. SEE measurements will be performed from the time of aircraft power-up on the ground throughout the flight regime until systems power-off after landing.

Huff, H.↗
DOE OSTI2016

The establisment of an achievement test for determination of primary teachers’ knowledge level of earthquake

In this study it was aimed to improve an academic achievement test to establish the students’ knowledge about the earthquake and the ways of protection from earthquakes. In the method of this study, the steps that Webb (1994) was created to improve an academic achievement test for a unit were followed. In the developmental process of multiple choice test having 25 questions, was prepared to measure the pre-service teachers’ knowledge levels about the earthquake and the ways of protection from earthquakes. The multiple choice test was presented to view of six academics (one of them was from geographic field and five of them were science educator) and two expert teachers in science Prepared test was applied to 93 pre-service teachers studying in elementary education department in 2014-2015 academic years. As a result of validity and reliability of the study, the test was composed of 20 items. As a result of these applications, Pearson Moments Multiplication half-reliability coefficient was found to be 0.94. When this value is adjusted according to Spearman Brown reliability coefficient the reliability coefficient was set at 0.97.

42 ENGINEERING↗
DOE OSTI2014

Parametric Thermal Models of the Transient Reactor Test Facility (TREAT)

This work supports the restart of transient testing in the United States using the Department of Energy’s Transient Reactor Test Facility at the Idaho National Laboratory. It also supports the Global Threat Reduction Initiative by reducing proliferation risk of high enriched uranium fuel. The work involves the creation of a nuclear fuel assembly model using the fuel performance code known as BISON. The model simulates the thermal behavior of a nuclear fuel assembly during steady state and transient operational modes. Additional models of the same geometry but differing material properties are created to perform parametric studies. The results show that fuel and cladding thermal conductivity have the greatest effect on fuel temperature under the steady state operational mode. Fuel density and fuel specific heat have the greatest effect for transient operational model. When considering a new fuel type it is recommended to use materials that decrease the specific heat of the fuel and the thermal conductivity of the fuel’s cladding in order to deal with higher density fuels that accompany the LEU conversion process. Data on the latest operating conditions of TREAT need to be attained in order to validate BISON’s results. BISON’s models for TREAT (material models, boundary convection models) are modest and need additional work to ensure accuracy and confidence in results.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗
DOE OSTI2017

Gearbox Reliability Collaborative Gearbox 3 Planet Bearing Calibration

The Gearbox Reliability Collaborative gearbox was redesigned to improve its load-sharing characteristics and predicted fatigue life. The most important aspect of the redesign was to replace the cylindrical roller bearings with preloaded tapered roller bearings in the planetary section. Similar to previous work, the strain gages installed on the planet tapered roller bearings were calibrated in a load frame. This report describes the calibration tests and provides the factors necessary to convert the measured units from dynamometer testing to bearing loads, suitable for comparison to engineering models.

17 WIND ENERGY↗
NASA NTRS1978

A miniaturized digital telemetry system for physiological data transmission

A physiological date telemetry system, consisting basically of a portable unit and a ground base station was designed, built, and tested. The portable unit to be worn by the subject is composed of a single crystal controlled transmitter with AM transmission of digital data and narrowband FM transmission of voice; a crystal controlled FM receiver; thirteen input channels follwed by a PCM encoder (three of these channels are designed for ECG data); a calibration unit; and a transponder control system. The ground base station consists of a standard telemetry reciever, a decoder, and an FM transmitter for transmission of voice and transponder signals to the portable unit. The ground base station has complete control of power to all subsystems in the portable unit. The phase-locked loop circuit which is used to decode the data, remains in operation even when the signal from the portable unit is interrupted.

Portnoy, W. M.↗
DOE OSTI2016

Comparison of Subdivided Versus Full-Length Fuel Pin Burnup in the ATF-2 Safety Analysis

The Accident Tolerant Fuels (ATF) campaign, under the Fuel Cycle Research and Development (FCRD) Advanced Fuels program, was developed after the Fukushima Daiichi Nuclear Power Plant disaster in 2011. Under ATF, fuel and cladding concepts are to be developed and tested that may more readily withstand an accident similar to the one that occurred at Fukushima Daiichi. ATF is a combination of industry, universities, and national laboratories in an effort to develop advanced accident tolerant cladding and fuel concepts. The end goal of the ATF program is to insert a lead test rod (LTR) or lead test assembly (LTA) into an operating commercial power light water reactor by 2022. In order to meet this 2022 insertion goal, ATF is split into three separate phases: ATF-1, ATF-2, and ATF-3. The first phase of the ATF program, ATF-1, is the concept feasibility study and early irradiation testing. Feasibility, fabrication, and out-of-pile testing are happening at universities and laboratories all over the United States. Irradiation testing of these concepts is happening at the Advanced Test Reactor (ATR) at the Idaho National Laboratory (INL). Early irradiation testing involves testing clad and/or fuel in drop-in capsules in the ATR. Currently, these capsules are in the relatively low-flux positions in the ATR, but some newer concepts and concepts that require higher burnup will be moved to the higher-flux positions later on during irradiation. Currently, Oak Ridge National Laboratory (ORNL), Westinghouse Electric Company, Areva, and General Electric (GE) have inserted capsules for ATF-1, although more concepts are planned. The second phase of ATF, ATF-2, is the focus of this paper. ATF-2 is the loop testing of fuel pins with new cladding and fuel concepts to simulate pressurized water reactor (PWR) and boiling water reactor (BWR) environments. ATF-2 will concurrently be happening at the ATR and at the Halden Reactor in Norway. The ATF-2 irradiation at the ATR will only simulate a PWR environment. ATF-2 will be inserted into the ATR pressurized water loop, Loop 2A, in the Center Flux Trap (CFT), where chemistry, temperature, and pressure can all be controlled separately from the primary coolant system and other loops in ATR. Loop 2A will be borated, pressurized to 2200 psi nominal, and have an average water temperature of 300 deg. C. A borated loop with fueled rodlets is extremely rare for Nuclear Energy experiments in the ATR, so ATF-2 will demonstrate new and unique capabilities for INL. ATF-3 is the testing of fresh and irradiated ATF concepts at the Transient Reactor Test (TREAT) Facility. The TREAT Reactor is planned for restart, re-establishing U.S. transient testing capabilities after nearly 20 years of non-operations. TREAT will test ATF concepts under transient conditions, such as a reactivity insertion accident. In addition to fresh fuel pins, TREAT will use from ATF2 and do transient testing on those irradiated pins. The information TREAT will provide to the vendors to support fuel licensing will be valuable, showing that these concepts do enhance the accident tolerance of the fuel in commercial reactors. (author)

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
NASA NTRS2024

Exploration Extravehicular Mobility Unit (xEMU) Chamber B Thermal Vacuum “Suit 2” Pressure Garment System Test Article Results

NASA’s Exploration Extravehicular Mobility Unit (xEMU) is the government reference next-generation spacesuit design and is engineered to protect astronauts from extreme lunar environmental temperatures. To evaluate the xEMU hardware thermal requirements, the xEMU Testing Team invented, designed, and executed a dual-suit, uncrewed thermal vacuum (TVAC) test at Johnson Space Center’s (JSC) Chamber B. This paper details the test results from the “Suit 2” Pressure Garment System (PGS) test article. The primary objective of the “Suit 2” PGS test article was to evaluate system-level suit heat leak and Environmental Protection Garment (EPG) thermal performance. Eleven unique thermal profiles were tested including both cold and hot environmental cases over the course of five continuous days of testing. The radiative thermal environment was controlled through exposure to liquid-nitrogen shrouds on the chamber walls and a heater cage surrounding the test article. This paper will principally focus on system-level thermal results from the “Suit 2” PGS test article. This paper will examine data collected from one-hundred and seventy thermocouples located in critical locations inside and outside of the suit, as well as seven resistance thermometers (RTDs) for calorimetry to determine total heat flux in and out of the suit. The test data will be compared against the system-level PGS thermal models for model validation. To conclude, this paper will address knowledge gaps presented by unmanned xPGS thermal vacuum testing and the current state of lunar xPGS thermal modeling and testing.

xEMU↗
NASA NTRS1974

Absolute pressure transducers for space shuttle and orbiter propulsion and control systems

A preliminary design was completed, reviewing of such subjects as: the trade studies for media isolation and one sensor vs. two sensors for two bridges; compensation resistors; unit design; hydrogen embrittlement; sealing techniques and test station design. A design substantiation phase was finished, consisting of testing of a prototype unit and fabrication technique studies. A cryogenic test station was implemented and prototype sensor cells were fabricated, sensors assembled, and cryogenic tests performed.

Bolta, J. J.↗
NASA NTRS2001

Updated Electronic Testbed System

As we continue to advance in exploring space frontiers, technology must also advance. The need for faster data recovery and data processing is crucial. In this, the less equipment used, and lighter that equipment is, the better. Because integrated circuits become more sensitive in high altitude, experimental verification and quantification is required. The Center for Applied Radiation Research (CARR) at Prairie View A&M University was awarded a grant by NASA to participate in the NASA ER-2 Flight Program, the APEX balloon flight program, and the Student Launch Program. These programs are to test anomalous errors in integrated circuits due to single event effects (SEE). CARR had already begun experiments characterizing the SEE behavior of high speed and high density SRAM's. The research center built a error testing system using a PC-104 computer unit, an Iomega Zip drive for storage, a test board with the components under test, and a latchup detection and reset unit. A test program was written to continuously monitor a stored data pattern in the SRAM chip and record errors. The devices under test were eight 4Mbit memory chips totaling 4Mbytes of memory. CARR was successful at obtaining data using the Electronic TestBed System (EBS) in various NASA ER-2 test flights. These series of high altitude flights of up to 70,000 feet, were effective at yielding the conditions which single event effects usually occur. However, the data received from the series of flights indicated one error per twenty-four hours. Because flight test time is very expensive, the initial design proved not to be cost effective. The need for orders of magnitude with more memory became essential. Therefore, a project which could test more memory within a given time was created. The goal of this project was not only to test more memory within a given time, but also to have a system with a faster processing speed, and which used less peripherals. This paper will describe procedures used to build an updated Electronic Testbed System.

Brewer, Kevin L.↗
NASA NTRS2005

Performance Testing of the Vapor Phase Catalytic Ammonia Removal Engineering Development Unit

This paper describes the results of performance testing of the Vapor Phase Catalytic Ammonia Removal (VPCAR) technology. The VPCAR technology is currently being developed by NASA as a Mars transit vehicle water recycling system. NASA has recently completed-a grant-to develop a next generation VPCAR system. This grant concluded with the shipment of the final deliverable to NASA on 8/31/03. This paper presents the results of mass, power, volume, and acoustic measurements for the delivered system. Product water purity analysis for a Mars transit mission and a simulated planetary base wastewater ersatz are also provided.

Flynn, Michael↗