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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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All sourcesNASA NTRSDOE OSTI
NASA NTRS2010

Aero-Thermal Calibration of the NASA Glenn Icing Research Tunnel (2004 and 2005 Tests)

A full aero-thermal calibration of the NASA Glenn Icing Research Tunnel was completed in 2004 following the replacement of the inlet guide vanes upstream of the tunnel drive system and improvement to the facility total temperature instrumentation. This calibration test provided data used to fully document the aero-thermal flow quality in the IRT test section and to construct calibration curves for the operation of the IRT. The 2004 test was also the first to use the 2-D RTD array, an improved total temperature calibration measurement platform.

Arrington, E. Allen↗
DOE OSTI2020

Hyperon III: $$K^{-}p - \pi \varSigma $$ coupled-channel dynamics in the $$\varLambda (1405)$$ mass region

Abstract Low-energy data on the three charge states in $$\gamma p \rightarrow K^+(\varSigma \pi )$$ γ p → K + ( Σ π ) from CLAS at JLab, on $$K^-p\rightarrow \pi ^0\pi ^0\varLambda $$ K - p → π 0 π 0 Λ and $$\pi ^0\pi ^0\varSigma $$ π 0 π 0 Σ from the Crystal Ball at BNL, bubble chamber data on $$K^-p\rightarrow \pi ^-\pi ^+\pi ^{\pm }\varSigma ^{\mp }$$ K - p → π - π + π ± Σ ∓ , low-energy total cross sections on $$K^-$$ K - induced reactions, and data on the $$K^-p$$ K - p atom are fitted with the BnGa partial-wave-analysis program. We find that the data can be fitted well with just one isoscalar spin-1/2 negative-parity pole, the $$\varLambda (1405)$$ Λ ( 1405 ) , and background contributions. In a fit with one isocsalar state, the $$\varLambda (1405)$$ Λ ( 1405 ) structure can be determined as a dominantly SU(3) singlet state. A fit with two isoscalar singlet states, with imposed properties of the low-mass state, is, however, also not incompatible with data.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2025

Microstructure Scale Lithium-Ion Battery Modeling: Part III. When and Where Lithium Plating Occurs and its Correlation with the Electrode Microstructure

Li-ion battery performance and degradation are closely related to the cell’s underlying electrode microstructure. Electrode microstructures are typically characterized with volume-averaged properties that neglect the impact of local heterogeneities. However, local heterogeneities create hot spots that can trigger degradation onset. Herein, a microstructure scale electrochemical model is used to investigate the impact of microstructure heterogeneity on lithium plating. The model predicts lithium plating is not uniform, even when considering a relatively small portion of the electrode (a cross-sectional area of 154×144 µm 2 ), preferring to plate on larger particles as compared to smaller particles. While local heterogeneities control where plating occurs, the model predicts that volume-averaged properties control when plating occurs. Additionally, the model predicts that the active material specific surface area has a linear relationship with the plating onset. However, the linear relationship between increased active material surface area and delayed plating response appears to be sensitive to the microstructure feature used to increase the active interface area. Here, a comparative case-study is explored where the specific surface area is increased by either reducing the active material particle diameter, adding open-porosity cracks, or increasing the active material surface roughness. The model predicts that increasing the specific surface area by reducing the active material particle diameter is the most effective strategy for delaying lithium plating. At 6C, reducing particle size is shown to be 3 and 20 times more effective than, respectively, adding open-porosity cracks and increasing surface roughness. A dual-layer electrode architecture combining gradations both for average properties and uniformities is eventually proposed to improve homogeneous material utilization and reduce degradation at high charge rates.

25 ENERGY STORAGE↗
DOE OSTI2022

Quality Guidelines for Energy System Studies - Capital Cost Scaling Methodology: Revision 4a Report

Costs are frequently required as part of systems analysis work at NETL. Many of the cost results provided as part of systems analysis work were created with the use of scaling, since obtaining new vendor-supplied cost quotes for each category developed by NETL would be prohibitively time consuming and costly. Additionally, many of the technologies being investigated by NETL have not progressed far enough to have quotable costs. The costs are scaled from a quote for a similar plant configuration by use of various equations that typically employ at least one process parameter (e.g., coal-feed rate, oxidant-feed rate) and often an exponent. The primary purpose of the exponent is to account for economies of scale (i.e., as equipment size gets larger, it gets progressively cheaper to add additional capacity). The purpose of this section of the QGESS report is to provide a standard basis for scaling costs, with specific emphasis on scaling exponents. The intention of having a standardized document is to provide guidelines for proper procedures to reduce the potential of errors and increase credibility through consistency.

99 GENERAL AND MISCELLANEOUS↗
NASA NTRS1990

Modelling and performance analysis of four and eight element TCAS

This semi-annual report describes the work performed during the period September 1989 through March 1990. The first section presents a description of the effect of the engines of the Boeing 737-200 on the performance of a bottom mounted eight-element traffic alert and collision avoidance system (TCAS). The second section deals exclusively with a four element TCAS antenna. The model obtained to simulate the four element TCAS and new algorithms developed for studying its performance are described. The effect of location on its performance when mounted on top of a Boeing 737-200 operating at 1060 MHz is discussed. It was found that the four element TCAS generally does not perform as well as the eight element TCAS III.

Sampath, K. S.↗
NASA NTRS1991

Four dimensional reconstruction and analysis of plume images

A number of methods have been investigated and are under current investigation for monitoring the health of the Space Shuttle Main Engine (SSME). Plume emission analysis has recently emerged as a potential technique for correlating the emission characteristics with the health of an engine. In order to correlate the visual and spectral signatures of the plume emission with the characteristic health monitoring features of the engine, the plume emission data must be acquired, stored, and analyzed in a manner similar to flame emission spectroscopy. The characteristic visual and spectral signatures of the elements vaporized in exhaust plume along with the features related to their temperature, pressure, and velocity can be analyzed once the images of plume emission are effectively acquired, digitized, and stored on a computer. Since the emission image varies with respect to time at a specified planar location, four dimensional visual and spectral analysis need to be performed on the plume emission data. In order to achieve this objective, feasibility research was conducted to digitize, store, analyze, and visualize the images of a subsonic jet in a cross flow. The jet structure was made visible using a direct injection flow visualization technique. The results of time-history based three dimensional reconstruction of the cross sectional images corresponding to a specific planar location of the jet structure are presented. The experimental set-up to acquire such data is described and three dimensional displays of time-history based reconstructions of the jet structure are discussed.

Dhawan, Atam P.↗
NASA NTRS1993

Stripping of a planetary nebula from the globular cluster M22

High-spatial resolution imaging in the O III lambda 5007 line of a planetary nebula (PN) in the globular cluster M22 reveals a strongly asymmetric (half-moon shaped) nebular morphology. We confirm that this peculiar morphology is caused by the distortion of stellar ejecta by the ram pressure of the ambient interstellar medium (ISM) through which the cluster is moving with a high velocity of 200 km/s. Emission knots visible in the leading (upstream) nebular section confirm theoretical expectations that the shell should have been fragmented by the Rayleigh-Taylor instability. Stripping of the PN from M22 by the ambient ISM is the first direct evidence for removal of gas from globular clusters. M22 is at a favorable location for the ram-pressure stripping to be effective, only 400 pc below the Galactic plane, well within a 2 kpc thick layer of ionized gas enveloping the plane. Ionized (or possibly neutral) gas in this layer, with a hydrogen density of about 0.1 cu/cm, is responsible for the observed interaction.

Borkowski, Kazimier J.↗
NASA NTRS1988

A 21 cm survey of the Pisces-Perseus supercluster. III - The region north of +38 degrees

As part of a comprehensive survey of galaxies in the region of the Pisces-Perseus supercluster and its surroundings, 21-cm line observations obtained with the NRAO 91-m telescope are presented for 383 galaxies in the right ascension range from 22 to 10 hr and north of +38 deg declination. Recent improvements to the Green Bank receiver/feed system have dramatically raised detection rates at the distance of Pisces-Perseus (cz = +5000 km/s). The present study has contributed to double the number of known redshifts outside rich clusters in this section of the sky. The H I content of the current sample, as expressed in terms of the H I mass expected for a galaxy of the same optical size and morphology, matches the standard of normalcy established for isolated galaxies.

Haynes, Martha P.↗
DOE OSTI2020

Primary intrinsic defects and their charge transition levels in β–Ga 2 O 3

A steady-state photocapacitance (SSPC) setup directly connected to the beamline of a MeV ion implanter is utilized to study primary intrinsic defects in β – Ga 2 O 3 generated by He implantation at cryogenic temperatures (120 K). At low temperatures, the migration of defects is suppressed, and hence the generation of primary intrinsic defects is expected to prevail. SSPC measurements reveal defect-related optical transitions in halide vapor-phase epitaxy (HVPE) -grown β – Ga 2 O 3 thin films with onset energies at 1.3 ( T 1 ) , 1.7 ( T 2 ) , 1.9 ( T 3 ) , 2.6 ( T 4 ) , 3.7 ( T 5 ) , and 4.2 eV ( T 6 ) . T 2 , T 4 , T 5 , and T 6 were observed in as-received HVPE-grown β – Ga 2 O 3 thin films, whereby T 2 is only sporadically observed. The introduction rates for T 3 , T 4 , as well as T 6 indicate an origin related to primary intrinsic defects. Notably, T 1 and T 3 are only observed after He implantation at cryogenic temperatures. Hybrid-functional calculations were performed to estimate the optical absorption cross-section spectra for the gallium ( Ga i ) and oxygen ( O i ) interstitials as well as the corresponding vacancies ( V Ga and V O , respectively), and compared with the measured onsets for optical absorption found by SSPC measurements. Indeed, we propose T 3 to be associated with Ga i ( + / + 2 ) and/or V GaI ( - 3 / - 2 ) , while T 4 is suggested to be related to V O K ( 0 / + ) ( K = I , II , III ) and/or V GaII ( - 3 / - 2 ) . Additionally, several further charge-state transition levels associated with V GaI and V GaII may contribute to T 4 and T 6 . We further studied the kinetics of the defects created with He implantation by exposing the sample to room temperature. The kinetics observed for T 3 and T 4 further support the proposed assignments of the corresponding defect signatures.

36 MATERIALS SCIENCE↗
NASA NTRS1975

Approximate solutions of radiative transfer in dusty nebulae. 2: Hydrogen and helium

The ionization structure of hydrogen and helium in dusty nebulae is discussed. The general equations for pure hydrogen nebulae are modified to include helium. An approximate analytic solution is presented for Stroemgren radii of hydrogen and helium in the absence of dust. It is shown that these results, with simple modifications, are also applicable to dusty nebulae where the effective absorption cross section of dust grains varies slowly with frequency in the 1000 to 200A range. No analytic solutions are possible if this cross section varies rapidly with frequency. In this case, however, simple coupled differential equations are derived. Approximate analytic expressions are presented for evaluation of the variation of the fraction of ionizing radiation absorbed by dust and the ratio of the volume emission measures of He II to H II regions with the spectrum of the ionizing source, helium abundance, and absorption properties of dust. The effects of dust on the He III zone are discussed. Results are restricted to spherically symmetric nebulae, but nonuniform gas and dust distributions and clumpiness can be taken into account.

Dana, R. A.↗
DOE OSTI2023

Finding Of Adverse Effect and Proposed Mitigation for the Removal of Joshua Trees at Building 23-210, Mercury, Area 23, Nevada National Security Site, Nye County, Nevada

The U.S. Department of Energy (DOE), National Nuclear Security Administration Nevada Field Office (NNSA/NFO) recently removed two fallen Joshua trees that were part of an Accessory Resource (AR) to the former Department of Defense (DOD) Motor Pool Maintenance Compound in Mercury (Nevada State Historic Preservation Office [SHPO] Resource No. C307) on the Nevada National Security Site (NNSS) in Nye County, Nevada (Figure 1). The Joshua trees were part of AR3, a landscaped feature at the entrance to the compound. There are two remaining Joshua trees at risk of falling which may require removal in the future. The NNSA/NFO is proactively consulting with the SHPO regarding the potential removal of the remaining two trees. The purpose of the undertaking is to ensure that dead or dying Joshua trees do not cause damage to the remaining landscape elements, nor injury to NNSS employees. The NNSA/NFO will implement this undertaking in accordance with the Programmatic Agreement between the National Nuclear Security Administration Nevada Field Office and the Nevada State Historic Preservation Officer Regarding Modernization and Operational Maintenance of the Nevada National Security Site, at Mercury in Nye County, Nevada, hereafter referred to as the Mercury PA. Building 23-210 was the DOD’s motor vehicle maintenance compound constructed in 1951. The compound included its own repair shop and fuel station. The town of Mercury and the immediate surrounding area have been formally determined eligible for listing in the National Register of Historic Places (National Register, NRHP) as the Mercury Historic District (MHD, SHPO Resource No. D230) under Criteria A and C for their importance in supporting nuclear testing and scientific research from 1951 through 1992. The former DOD Motor Pool Compound was identified as a contributing element to the MHD in a 2018 architectural survey of the district (Reno et al. 2018) and recorded on a Nevada Architectural Resource Assessment (ARA) form (Reno et al. 2017). The foundation for Building 23-210 was also identified in Appendix C of the Mercury PA as a Category III contributing element with three contributing ARs. Category III properties are those that may include elements for which there are several representatives in the MHD, such as foundations, and those elements which possess characteristics that are not unique to the MHD and are commonly found in other non-NNSS facilities. The former DOD compound, which is identified by the foundation for the Building 23-210 and its ARs, is a historic property for the purposes of compliance with Section 106 of the National Historic Preservation Act (NHPA) and subject to the stipulations of the Mercury PA.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2022

Probing Optimal Reaction Energy for Synthesis of Element 119 from 51 V+ 248 Cm Reaction with Quasielastic Barrier Distribution Measurement

Here, the quasielastic barrier distribution of 51 V+ 248 Cm was extracted by measuring the excitation function of quasielastic backscattering using a gas-filled recoil ion separator, GARIS-III. The obtained barrier distribution is well explained by the coupled-channels calculation, indicating a significant effect of the rotational excitation of deformed 248 Cm. From the measured average Coulomb barrier height and deformation parameters of 248 Cm, the side-collision energy leading to a compact configuration of colliding nuclei was obtained. The relation between the side collision energy and the excitation function of the evaporation-residue cross sections in the 48 Ca+ 248 Cm system was evaluated as a reference for the 51 V+ 248 Cm case. The optimal reaction energy to synthesize a new element 119 at the 51 V+ 248 Cm fusion reaction (3n and 4n channels) was estimated with an aid of these experimental data.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
NASA NTRS1986

Thermal-mechanical fatigue behavior of nickel-base superalloys

The main achievements of a 36-month research program are presented. The main objective was to gain more insight into the problem of crack growth under thermal mechanical fatigue (TMF) conditions. This program was conducted at M.I.T. for the period of September 1982 to September 1985. The program was arranged into five technical tasks. Under Task I, the literature of TMF data was reviewed. The goal was to identify the crack propagation conditions in aircraft engines (hot section) and to assess the validity of conventional fracture mechanics parameters to address TMF crack growth. The second task defined the test facilities, test specimen and the testing conditions needed to establish the effectiveness of data correlation parameters identified in Task I. Three materials (Inconel X-750, Hastelloy-X, and B-1900) were chosen for the program. Task II was accomplished in collaboration with Pratt & Whitney Aircraft engineers. Under Task III, a computerized testing system to measure the TMF behavior (LCF and CG behaviors) of various alloys systems was built. The software used to run isothermal and TMF tests was also developed. Built around a conventional servohydraulic machine, the system is capable of push-pull tests under stress or strain and temperature controlled conditions in the temperature range of 25C to 1050C. A crack propagation test program was defined and conducted under Task IV. The test variables included strain range, strain rate (frequency) and temperature. Task V correlated and generalized the Task IV data for isothermal and variable temperature conditions so that several crack propagation parameters could be compared and evaluated. The structural damage (mode of cracking and dislocation substructure) under TMF cycling was identified and contrasted with the isothermal damage to achieve a sound fundamental mechanistic understanding of TMF.

Pelloux, R. M.↗
NASA NTRS2003

High-Resolution Spectroscopic Database for the NASA Earth Observing System Program

The purpose of this project is to develop and enhance the HITRAN molecular spectroscopic database and associated software to support the observational programs of the Earth Observing System (EOS). In particular, the focus is on the EOS projects: the Atmospheric Infrared Sounder (AIRS), the High-Resolution Dynamics Limb Sounder (HIRDLS), Measurements of Pollution in the Troposphere (MOPITT), the Tropospheric Emission Spectrometer (TES), and the Stratospheric Aerosol and Gas Experiment (SAGE III). The HITRAN program is also involved in the Ozone Monitoring Experiment (OMI). The data requirements of these programs in terms of spectroscopy are varied with respect to constituents being observed, required remote-sensing parameters, and spectral coverage. A general requisite is for additional spectral parameters and improvements to existing molecular bands sufficient for the simulation of the observations leading to retrieval of the atmospheric state. In addition, cross-section data for heavier molecular species must be expanded and made amenable to modeling in remote sensing. The effort in the project also includes developing software and distribution to make access, manipulation, and use of HITRAN functional to the EOS program.

Rothman, Laurence↗
NASA NTRS2004

High-Resolution Spectroscopic Database for the NASA Earth Observing System Program

The purpose of this project is to develop and enhance the HITRAN molecular spectroscopic database and associated - software to support the observational programs of the Earth observing System (EOS). In particular, the focus is on the EOS projects: the Atmospheric Infrared Sounder (AIRS), the High-Resolution Dynamics Limb Sounder (HIRDLS), Measurements of Pollution in the Troposphere (MOPITT), the Tropospheric Emission Spectrometer (TES), and the Stratospheric Aerosol and Gas Experiment (SAGE III). The HITRAN program is also involved in the Ozone Monitoring Experiment (OMI). The data requirements of these programs in terms of spectroscopy are varied with respect to constituents being observed, required remote-sensing parameters, and spectral coverage. A general requisite is for additional spectral parameters and improvements to existing molecular bands sufficient for the simulation of the observations leading to retrieval of the atmospheric state. In addition cross-section data for heavier molecular species must be expanded and made amenable to modeling in remote sensing. The effort in the project also includes developing software and distribution to make access, manipulation, and use HITRAN functional to the EOS program.

Rothman, Laurence S.↗
NASA NTRS2004

High Resolution Spectroscopic Database for the NASA Earth Observing System Program

The purpose of this project has been to develop and enhance the HITRAN molecular spectroscopic database and associated software to support the observational programs of the Earth Observing System (EOS). Emphasis has been on the EOS projects: the Atmospheric Infrared Sounder (AIRS), the High-Resolution Dynamics Limb Sounder (HIRDLS), Measurements of Pollution in the Troposphere (MOPITT), the Tropospheric Emission Spectrometer (TES), and the Stratospheric Aerosol and Gas Experiment (SAGE III). The HITRAN program is also involved in the Ozone Monitoring Experiment (OMI). The data requirements of these programs in terms of spectroscopy are varied with respect to constituents being observed, required remote-sensing parameters, and spectral coverage. A general requisite is for additional spectral parameters and improvements to existing molecular bands sufficient for the simulation of the observations leading to retrieval of the atmospheric state. In addition, cross-section data for heavier molecular species must be expanded and made amenable to modeling in remote sensing. The effort in the project also includes developing software and distribution to make access, manipulation, and use of HITRAN functional to the EOS program.

Rothman, Laurence↗
DOE OSTI2020

Distributed fiber sensing systems for 3D combustion temperature field monitoring in coal-fired boilers using optically generated acoustic waves (Final Report)

In this project, we have developed and tested three kinds of fiber optic sensing systems for real time monitoring of temperature variations within an industrial scale boiler furnace. The fiber optic sensing systems target spatial and temporal distributions of high temperature profiles in a boiler furnace in fossil power plants. The reconstructed temperature profile will provide critical input for the control mechanisms to optimize the combustion process. This temperature profile will address the essential problem for fossil power plants in achieving higher efficiency and fewer pollutant emissions. Acoustic pyrometer systems have been used to reconstruct temperature field of power plant boilers based on measuring TOF (times-of-flight) of sound waves along some straight paths in a 2D cross-section of the boiler. In this project, optically generated acoustic signals from a fiber optic sensing system have replaced the acoustic signals generated from an electrical transducer. A 3D reconstruction algorithm replaced the previous 2D model. In this project, three kinds of fiber optic sensing systems have been developed and tested. They are fiber optic sensing system I, fiber optic sensing system II (Distributed Sensing System I) and fiber optic sensing system III (Distributed Sensing System II). For fiber optic sensing system I, the fiber optic ultrasound generator acts as a signal generator. A microphone, hydrophone or other electronic devices serve as a signal receiver. In this system, there are one generator and one receiver. Distance test, water temperature test, air temperature test, air temperature reconstruction, and GE ISBF pilot test were performed by Fiber optic sensing system I. The fiber optic sensing system I successfully detected temperature in all these tests. We got 2D temperature reconstruction results by using the fiber optic sensing system I and it matched the reference data. The fiber optic sensing system I successfully survived in GE ISBF boiler environment (480 °F). For fiber optic sensing system II (Distributed Sensing System I), it is an all optical ultrasound system. The fiber optic ultrasound generator acts as a signal generator. Fiber Bragg Grating (FBG) and Fabry-Perot (FP) sensor act as a signal receiver. In this system, there is one generator and one receiver. Aluminum plate temperature test, furnace high temperature test, and GE ISBF pilot test were performed by the fiber optic sensing system II. Fiber optic sensing system II successfully detected the temperature in all these tests. The fiber optic sensing system II successfully survived at up to 700 °C furnace environment and 320 °C GE ISBF boiler environment. For fiber optic sensing system III (Distributed Sensing System II), it is also an all optical ultrasound system. The fiber optic ultrasound generator acts as a signal generator. Multiple FP fiber sensors act as signal receivers. In this system, there is one generator and three receivers. Three GE ISBF pilot tests were performed by fiber optic sensing system III. The fiber optic sensing system III survived in the cold flow tests in GE’s ISBF pilot test facility. However, we didn’t get high temperature data by using this system since the nanosecond laser issues. During the period of the project, test trials, data simulation and algorithm optimization was performed successfully. For real time temperature field construction, the sampling rate must be fast enough to capture the field variations. The technology of Code-division multiple access (CDMA) is well studied which could allow parallel multiplexing, even if signals overlap in time or frequencies. Moreover, it has been known that extending the length of signal significantly improves SNR. For acoustic signals, these multiplexing techniques have also been widely used, mainly for sonar and acoustic communications. The CDMA modulation technique has been proposed and studied to guarantee high network throughput, low channel access delay and low energy consumption. We have studied the temperature field reconstruction using Gaussian Radial Basis Functions (GRBF)-based approximation approach. Reconstruction of 3D temperature field using Neural Networks with measured TOF and known propagation paths is feasible. 2D and 3D temperature field reconstruction simulation results are achieved. The milestone status is shown in Table 1. We finished milestone 1-8 and milestone 10. For milestone 9, we did three pilot tests by using the fiber optic sensing system III (Distributed Sensing System II) at GE Power. However, due to the failure of the ns laser, we did not get the temperature results. We conducted some additional tasks that were not originally proposed: 1) We fabricated a fiber optic sensing system I and did a pilot test based on this system. 2) In the proposal, we proposed two pilot tests at GE Power. In reality, we finished at least seven pilot tests at GE Power. GE Power has made a lot of efforts for supporting the pilot tests. 3) We got a simulation results based on CDMA. In summary, most of the tasks have been accomplished. The outcome of this project removed a few barriers that hinder the achievement of the final product of the distributed sensing systems. With the successful accomplishment of this project, a prototype of the fiber optic sensing system can be fabricated to attract more interests from companies and other funding agencies.

47 OTHER INSTRUMENTATION↗
DOE OSTI2021

Site-Directed Research & Development Annual Report Overview FY 2020

The SDRD program’s annual report for fiscal year 2020 consists of two parts: the program overview, which contains three major sections, Program Description, Program Accomplishments, and Program Value, and individual project report summaries published electronically on the Nevada National Security Site’s website, www.nnss.gov/pages/programs/sdrd.html. Complete technical reports for concluding projects are available from the Office of Scientific and Technical Information (OSTI) or the principal investigator.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗