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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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10 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1980

Evaluation of thermal energy storage for the proposed Twin Cities District Heating system

The technical and economic feasibility of incorporating thermal energy storage components into the proposed Twin Cities District heating project was evaluated. The technical status of the project is reviewed and conceptual designs of district heating systems with and without thermal energy storage were compared in terms of estimated capital requirements, fuel consumption, delivered energy cost, and environmental aspects. The thermal energy storage system is based on cogeneration and the storage of heat in aquifers.

Meyer, C. F.↗
NASA NTRS1975

Applications of ERTS imagery to mappings sediments of the Twin Cities Metropolitan area

ERTS images were compared to surficial geologic maps, prepared through traditional field studies. Lithologic boundaries, bedrock outcrops, bedrock structures, and geomorphologic features were examined. An area southeast of the Twin Cities, located chiefly in northern Dakota County was studied, as well as the New Brighton 15-minute quadrangle located in portions of Ramsey and Anoka Counties. Visual comparison of geologic maps and ERTS imagery demonstrated the limitations of this approach to geological investigations. Bedrock outcrops and bedrock structure in the metropolitan area do not appear on ERTS imagery. However, certain glacial sediments can be identified and are potentially mappable. Certain geomorphological features were also discernable.

Poppe, J. R.↗
NASA NTRS1972

Land use management in Minnesota

The author has identified the following significant results. Preliminary analysis of bulk imagery suggests that the forty-acre data cell used in the Minnesota Land Management Information Systems (MLMIS) can be utilized in interpretation of ERTS-1 data. High quality bulk images of the Twin Cities metropolitan area suggest that detail in urban land use patterns is much greater than originally anticipated. This implies a greater work effort in this area than was planned. Furthermore, the forest classes of land use can also be usefully divided into subcategories. Preliminary analysis of one rather low quality image also indicates that subclasses of wetlands can be identified. Prospects are bright for improving the potential detail that ERTS-1 can contribute to MLMIS.

Sizer, J. E.↗
NASA NTRS1980

Subcontracted activities related to TES for building heating and cooling

The subcontract program elements related to thermal energy storage for building heating and cooling systems are outlined. The following factors are included: subcontracts in the utility load management application area; life and stability testing of packaged low cost energy storage materials; and development of thermal energy storage systems for residential space cooling. Resistance storage heater component development, demonstration of storage heater systems for residential applications, and simulation and evaluation of latent heat thermal energy storage (heat pump systems) are also discussed. Application of thermal energy storage for solar application and twin cities district heating are covered including an application analysis and technology assessment of thermal energy storage.

Martin, J.↗
NASA NTRS1990

Electron microscopy study of the iron meteorite Santa Catharina

A characterization of the microstructural features of Santa Catharina (SC) from the millimeter to submicron scale is presented. The same specimen was examined using an optical microscope, a scanning electron microscope, an electron probe microanalyzer, and an analytical electron microscope. Findings include the fact that SC metal nodules may have different bulk Ni values, leading to different microstructures upon cooling; that SC USNM 6293 is the less corroded sample, as tetrataenite exists as less than 10 nm ordered domains throughout the entire fcc matrix (it is noted that this structure is the same as that of the Twin City meteorite and identical to clear taenite II in the retained taenite regions of the octahedrites); that SC USNM 3043 has a more complicated microstructure due to corrosion; and that the low Ni phase of the cloudy zone was selectively corroded in some areas and formed the dark regions, indicating that the SC meteorite corrosion process was electrochemical in nature and may involve Cl-containing akaganeite.

Zhang, J.↗
NASA NTRS1997

Preliminary Report of NRC Twin Otter Operations in the 1997 Southern Great Plains Experiment

From June 18 to July 17, 1997, the NRC Twin Otter atmospheric research aircraft was operated from Oklahoma City, U.S.A., in the Southern Great Plains 1997 (SGP97) Hydrology Experiment. The primary role of the aircraft was to measure the vertical fluxes of sensible and latent heat, CO2, ozone and momentum in the atmospheric boundary layer, along with supporting meteorological and radiometric data. Approximately 400 flux runs and 100 soundings were flown in 27 project flights over rural areas near Oklahoma City. This preliminary report documents the flight program, lists the instrumentation aboard the aircraft, and presents a summary of run-averaged data from each flux run. These data are from the in-field analysis and must be considered preliminary. A re-analysis incorporating updated calibrations is planned for the fall of 1997 followed by a more comprehensive technical report.

MacPherson, J. Ian↗
NASA NTRS1975

Review of NASA short-haul studies

The paper summarizes the results of NASA-conducted technological and economic studies of low, medium, and high density short-haul transportation systems. Aircraft concepts considered included CTOL, RTOL, STOL, and general aviation aircraft. For low density systems, it was found that viable air service becomes possible if city pairs are at least 100 km apart and a two-way total travel demand of at least 200 daily passengers exists. Currently available aircraft were found suitable. The medium-density study showed that a 60-passenger twin engine turbofan was the best suited aircraft. For high density systems, STOL appears to be an economically viable means of reducing noise and congestion at major hub airports. Adequate runways 914 m in length or greater either already exist or could be added to most existing major hub airports.

Kenyon, G. C.↗
NASA NTRS1994

Magnetic Earth Ionosphere Resonant Frequencies (NASA-MEIRF Project)

During this current reporting period, the project has focused on completing Phase 1 of the field monitoring work and documenting research results. Highlights of these efforts include presentations of papers at the annual joint meeting of the American Physical Society/American Association of Physics Teachers, April 18-22, 1994, in Crystal City, Virginia, and at the International Space, Time, and Gravitation Conference and Etoiles de L'Ecole Polytechnique Symposium, May 23-28, 1994, in St. Petersburg, Russia. Field measurements of the background ultra low frequency (ULF) electromagnetic spectrum in the New Mexico and Texas regions show interesting differences. Included are papers entitled 'Triplet Solution of the Twin Paradox' and 'Classical Electron Mass and Fields, Part 3.'

Source record↗
NASA NTRS2024

Analysis of Hybrid Electric Aircraft Operations in the National Airspace System

This paper investigates the fuel burn and flight time impacts of hybrid electric aircraft operating in the National Airspace System. Future scenarios with hybrid electric flights and the same passenger travel capacity between city pairs as a baseline scenario, taken from historical data, were created. Aircraft that serviced select flights in the baseline scenario were replaced with hybrid electric aircraft based on the flight’s range and seat capacity. Additional hybrid electric flights were added to future scenarios when necessary to keep the future scenario passenger capacity equal or greater to that of the baseline scenario. The baseline and future scenarios were simulated in the NAS Digital Twin, a live, virtual, and constructive environment for building and executing simulations of the Nation Airspace System. Results showed that the future scenarios with hybrid electric flights saved fuel burn, but increased flight time. In the future scenarios, the additional hybrid electric flights did not cause any airports to exceed their operational capacity.

Simulation↗
NASA NTRSDate not supplied

Operating Hybrid Electric Aircraft in the National Airspace System

This paper investigates the fuel burn and flight time impacts of hybrid electric aircraft operating in the National Airspace System. Future scenarios with hybrid electric flights and the same passenger travel capacity between city pairs as a baseline scenario, taken from historical data, were created. Aircraft that serviced select flights in the baseline scenario were replaced with hybrid electric aircraft based on the flight’s range and seat capacity. Additional hybrid electric flights were added to future scenarios when necessary to keep the future scenario passenger capacity equal or greater to that of the baseline scenario. The baseline and future scenarios were simulated in the NAS Digital Twin, a live, virtual, and constructive environment for building and executing simulations of the Nation Airspace System. Results showed that the future scenarios with hybrid electric flights saved fuel burn, but increased flight time. In the future scenarios, the additional hybrid electric flights did not cause any airports to exceed their operational capacity.

hybrid electric aircraft↗