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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 19 records

Building partnerships for development of sustainable energy systems with atmospheric measurements

Atmospheric dynamics often play a critical role in the sustainability and reliability of diverse forms of energy production. This is especially true for the growing number of renewable energy deployments that harness aspects of the environment for power production. While the University of Memphis has a strong research background in energy systems, we have little experience working with the Earth and Environmental Systems Science Division (EESSD) and their associated User Facilities. Of particular interest to us is the Atmospheric Science Research and the Atmospheric Radiation Measurement (ARM) user facility to address surface-boundary layer interactions and physical phenomena. One of the major challenges for understanding and developing energy systems and management platforms is accurate modeling/forecasting of atmospheric conditions across disparate spatial and temporal scales. These conditions are often required to understand the lowest levels of the atmospheric boundary layer, but are also important to understand higher atmospheric conditions where aerosols affect cloud development. The objective of this work was to develop partnerships with national laboratories for collaboration on environmental science and its intersection with sustainable energy systems, as well as to leverage the ARM user facility data repositories to enhance our research capabilities in energy systems and their inter-dependence on environmental systems for future engagement with EESSD. Specifically, we accomplished these objectives by (1) developing collaborations with Oakridge National Laboratory ARM Data Science and Integration Group which resulted in student internships, (2) employed ARM data to develope modeling of the atmospheric boundary layer optical turbulence, and (3) optimally-sized large-scale renewable energy systems and their associated energy storage systems with ARM repository data.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

Q branches of the nu7 fundamental of ethane (C2H6) Integrated intensity measurements for atmospheric measurement applications

Laboratory spectra covering the nu7 band of ethane (C2H6) have been recorded, and measurements of integrated intensities of selected Q branches from these spectra are reported. The method by which the spectra were obtained is described, and a typical spectrum covering the PQ3 branch at 2976.8/cm is shown along with a plot of equivalent width vs. optical density for this branch. The values of the integrated intensities reported for each branch are the means of five different optical densities.

Rinsland, C. P.↗

Coherent CO2 lidar systems for remote atmospheric measurements

Several examples of applications of coherent CO2 Doppler lidar systems are summarized to illustrate the potential of these systems. The applications discussed include the use of continuous-wave systems for detecting and tracking aircraft wake vortices, transverse velocity measurements, and measurements of mass flow rates of high stack emissions. The use of pulsed coherent lidars is illustrated by applications involving the measurement of thunderstorm gust fronts, the measurement of wind profiles, and clear air turbulence detection. Following a summary of previous efforts, some current programs are reviewed. These include investigations into two-dimensional wind field measurements, atmospheric backscatter measurements, transverse velocity measurements, and the feasibility of space operations.

Bilbro, J. W.↗

Atmospheric measurements from satellites.

Atmospheric measurements from satellites, discussing ATS-1 cloud images for definition of wind and use of WEFAX through ATS 2 satellites for data transmission

Rados, R. M.↗

Simulations of X-59 Low-Booms Propagated Through Measured Atmospheric Profiles in Galveston, Texas

During NASA’s Quiet Supersonic Flights 2018 (QSF18) test, residents of Galveston, Texas and surrounding communities were exposed to low amplitude sonic booms for a community noise survey. Despite the flight test lasting only 11 days, substantial weather variability occurred including snow and record high temperatures. Similar atmospheric variability could occur in future community noise flight tests with the X-59 Quiet Supersonic Technology aircraft that is currently being constructed. X-59 is designed to have a Stevens Mark VII Perceived Level (PL) of 75 dB in a standard atmosphere. In this work, X-59’s low-boom performance in real atmospheres was tested by using NASA’s PCBoom code to simulate propagation of its nearfield pressure through the atmospheric profiles measured during QSF18. Results indicate undertrack booms would not exceed 75 PLdB in these atmospheres. A range of about 8.5 PLdB between the loudest and quietest undertrack boom was observed indicating adjustments to the X-59 flight condition may be needed to achieve target loudness levels during future sonic boom community noise surveys. Attenuation rate, ray tube area, path length and other quantities throughout propagation of the loudest and quietest booms are presented, which indicate humidity differences below 15kft were a primary driver of the PL differences.

sonic boom↗

Recent Advancements in Atmospheric Measurements Made from NASA Airborne Science Platforms

Techniques for making atmospheric measurements are as wide-ranging as the atmosphere is complex. From in situ measurements made by land, sea, or air, to remote sensing data collected by satellites orbiting the Earth, atmospheric measurements have been paramount in advancing the combined understanding of our planet. To date, many of these advancements have been enabled by NASA Airborne Science platforms, which provide unique opportunities to make these measurements in remote regions, and to compare them with an ever-increasing archive of remote satellite data. Here, we discuss recent advances and current capabilities of the National Suborbital Research Center (NSRC) which provides comprehensive instrumentation and data system support on a variety of NASA airborne research platforms. Application of these methods to a number of diverse science missions, as well as upcoming project opportunities, will also be discussed.

Steven Schill↗

A comparison of a coaxial focused laser Doppler system in atmospheric measurements

Measurements of atmospheric velocities and turbulence with the laser Doppler system were obtained, and the results compared with cup anemometer and hot-wire measurements in the same wind field. The laser Doppler velocimeter (LDV) is described along with the test procedures. It was found that mean values determined from the LDV data are within 5% of other anemometer data for long time periods, and the LDV measures higher velocities.

Karaki, S.↗

Simulations and case study of X-59 low-booms propagated through measured atmospheric profiles

NASA's X-59 Quiet Supersonic Technology aircraft will soon be used to collect data to support the development of a dose-response relationship between low-boom level and human perception. The X-59's low-boom level will depend on aircraft conditions and trajectory, which can be controlled, and on atmospheric conditions, which cannot be controlled. To assess variability in low-boom levels produced by realistic atmospheres, NASA's PCBoom code was used to simulate propagation of an X-59 nearfield pressure condition through atmospheric profiles measured during NASA's Quiet Supersonic Flights 2018 (QSF18) test. Despite QSF18 lasting only 11 days, substantial weather variability occurred including snow and record high temperatures. A PL range of about 8.5 dB was predicted due to the QSF18 atmospheric variability. These results demonstrate the necessity for X-59's flight condition to be adjusted based on atmospheric conditions in order to achieve desired loudness levels during community surveys. Undertrack booms' Perceived Levels (PL) were predicted not to exceed 75 dB, X-59's target level in a standard atmosphere. Attenuation rate, ray tube area, path length, and other quantities are presented throughout propagation for the atmospheres that produce the loudest and quietest booms. Humidity differences below 15kft were a primary driver of the PL differences.

X-59↗

BOREAS RSS-3 Atmospheric Measurements from a Helicopter-Mounted Sunphotometer

The BOREAS RSS-3 team collected and processed helicopter-based measurements of atmospheric conditions to estimates of aerosol optical thickness and atmospheric water vapor. The automatic sun-tracking photometer for helicopters was deployed during all three 1994 IFCs at numerous tower and auxiliary sites in both the NSA and the SSA. Six spectral channels (440, 540, 613, 670, 870, and 1030 nm) were chosen to span the visible and NIR wavelengths and to avoid gaseous absorption. One additional channel, 940 nm, was selected to measure the water column abundance above the helicopter platform. The data are stored in tabular ASCII files.

Hall, Forrest G.↗

Atmospheric measurements of carbonyl sulfide, dimethyl sulfide, and carbon disulfide using the electron capture sulfur detector

Measurements of atmospheric dimethyl sulfide (DMS), carbonyl sulfide (COS), and carbon disulfide (CS2) were conducted over the Atlantic Ocean on board the NASA Electra aircraft during the Chemical Instrumentation Test and Evaluation (CITE 3) project using the electron capture sulfur detector (ECD-S). The system employed cryogenic preconcentration of air samples, gas chromatographic separation, catalytic fluorination, and electron capture detection. Samples collected for DMS analysis were scrubbed of oxidants with NaOH impregnated glass fiber filters to preconcentration. The detection limits (DL) of the system for COS, DMS, and CS2 were 5, 5, and 2 ppt, respectively. COS concentrations ranged from 404 to 603 ppt with a mean of 489 ppt for measurements over the North Atlantic Ocean (31 deg N to 41 deg N), and from 395 to 437 ppt with a mean of 419 ppt for measurements over the Tropical Atlantic Ocean (11 deg S to 2 deg N). DMS concentrations in the lower marine boundary layer, below 600-m altitude, ranged from below DL to 150 ppt from flights over the North Atlantic, and from 9 to 104 ppt over the Tropical Atlantic. CS2 concentrations ranged from below DL to 29 ppt over the North Atlantic. Almost all CS2 measurements over the Tropical Atlantic were below DL.

Johnson, James E.↗

Assessment of Climatic and Anthropogenic Impacts on the Global Carbon Cycle Constrained by Atmospheric Measurements and Remote Sensing Data

This grant aimed to establish how the global carbon cycle has responded and will respond to global change. We proposed to use models to predict measurements of atmospheric CO2 concentration and C-13/C-12 isotopic ratio, and thereby to establish how sources and sinks of atmospheric CO2 have been influenced by climatic change and human activities. As the work progressed we developed strategies involving finding regional sources and sinks of atmospheric CO2 by an inverse approach, and studying their seasonal and interannual variability.

Keeling, Charles D.↗

Ultra Narrowband Optical Filters for Water Vapor Differential Absorption Lidar (DIAL) Atmospheric Measurements

Differential absorption lidar (DIAL) systems are being deployed to make vertical profile measurements of atmospheric water vapor from ground and airborne platforms. One goal of this work is to improve the technology of such DIAL systems that they could be deployed on space-based platforms. Since background radiation reduces system performance, it is important to reduce it. One way to reduce it is to narrow the bandwidth of the optical receiver system. However, since the DIAL technique uses two or more wavelengths, in this case separated by 0.1 nm, a fixed-wavelength narrowband filter that would encompass both wavelengths would be broader than required for each line, approximately 0.02 nm. The approach employed in this project is to use a pair of tunable narrowband reflective fiber Bragg gratings. The Bragg gratings are germanium-doped silica core fiber that is exposed to ultraviolet radiation to produce index-of-refraction changes along the length of the fiber. The gratings can be tuned by stretching. The backscattered laser radiation is transmitted through an optical circulator to the gratings, reflected back to the optical circulator by one of the gratings, and then sent to a photodiode. The filter reflectivities were >90 percent, and the overall system efficiency was 30 percent.

Stenholm, Ingrid↗

Laser Sounder Approach for Measuring Atmospheric CO2 from Orbit

We report on an active remote sensing approach using an erbium fiber amplifier based transmitter for atmospheric CO2 measurements in an overtone band near 1.57 microns and initial horizontal path measurements to less than 1% precision.

Krainak, Michael A.↗

Laser-excited fluorescence for measuring atmospheric pollution

System measures amount of given pollutant at specific location. Infrared laser aimed at location has wavelength that will cause molecules of pollutant to fluoresce. Detector separates fluorescence from other radiation and measures its intensity to indicate concentration of pollutant.

Menzies, R. T.↗