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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 811 records · Page 45

Urban Combined Heat and Power with Integrated Renewables and Energy Storage

This project demonstrated how incorporating a diverse generation and storage portfolio allows an urban district energy system to improve its efficiency by at least 50% and increase its backup power by at least 40% with a return on investment of at least ten years. The improvement was evaluated against the baseline operations for two urban district energy systems (DESs): a synthetic DES and a George Washington University DES. The DES techno-economic framework we developed yields reliability, resilience, and vulnerability indices for urban DESs (including generation and storage) with designation of which technologies improve the security and resiliency metrics by at least 20% compared to the status quo. The indices are benchmarked against baseline scenarios, and cost projections (capital cost and return on investment) to achieve the 20% improvement are reported. The energy management system we developed to conduct these analyses was incorporated into a user-friendly interface that can be used for decision-making by a user with no technical or programming background.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

High-Fidelity Building Emulator for Integrated Comfort and Energy Analysis using EnergyPlus and Radiance

The growing need for smart, energy-efficient, and occupant-centric buildings has created a demand for advanced control systems that can optimize building operations to balance energy savings, demand flexibility, and comfort. However, current building energy simulation tools, such as EnergyPlus, have limitations that hinder the development and evaluation of these complex control systems. To address this challenge, we introduce a high-fidelity building emulator that dynamically couples EnergyPlus with Radiance for enhanced daylight modeling. The introduced workflow allows researchers and practitioners to rapidly develop and evaluate innovative control solutions. An example study looking at a south-facing office zone revealed up to 67% deviation in predicted light levels, which can significantly impact building assessment.

Yu, Tammie↗

Ion dipole capture cross sections at low ion and rotational energies - Comparison of integrated capture cross sections with reaction cross sections for NH3 and H2O parent-ion collisions.

The numerical capture cross section is calculated from the capture ratio, defined as the fraction of trajectories reaching a prescribed minimum separation of 3 A. The calculated capture cross sections for a rotational temperature of 77 K suggest large reaction cross sections in 80 K experiments for the large dipole-moment target, methyl cyanide.

Dugan, J. V., Jr.↗

Integrated and spectral energy flows of the GLAS GCM

Methods to analyze the generation, transport, and dissipation of energy to study geophysical fluid flows are discussed. Energetics analyses are pursued in several directions: (1) the longitudinal and time dependence on the energy flow to the stratosphere was examined as a function of geographical sector; (2) strong and weak energy flows were correlated by medium range forecasts; (3) the one dimensional spectral results (Fourier services around latitude circles) were extended to spherical harmonics over a global domain; (4) the validity of vertical velocities derived from mass convergence was examined for their effect on the conversion of eddy available potential energy to eddy kinetic energy.

Tennebaum, J.↗

High temperature transport properties of air - N-O interaction energies and collision integrals

Potential curves for the higher-lying states of NO are used together with a general scattering code to compute accurate values of transport collision integrals for N(4S/0/)-O(3P) interactions. It is found that the major contribution to the collision integrals comes from these higher-lying states of NO. New values of the collision integrals for N(4S/0/)-N(4S/0/) and O(3P)-O(3P) interactions are computed as well. The tabulations of the collision integrals cover a broad range of temperatures from 250 to 100,000 K and can be used to determine transport properties such as viscosity, thermal conductivity, and the diffusion coefficient to the second order.

Levin, E.↗

The free-wake prediction of rotor hover performance using a vortex embedding method

A method is developed to predict the rotor hover performance. This method solves the compressible mass conservation equation much like current full potential codes and can therefore predict the transonic flows on a rotor. However, the newly developed approach also allows for the free convection of shed vorticity and permits the computation of the entire hover wake system. The method uses a vortex embedding scheme in potential flow and has been implemented in a computer code, HELIX -I. To predict power we implement a simple boundary layer and two different induced-drag integration schemes. The induced-drag is obtained from surface pressure integration and an energy flux integral. Comparisons between computations and experiment show good agreement for the prediction of power polars, surface pressure distribution, and tip vortex geometry.

Ramachandran, K.↗

STRV RADMON: An integrated high-energy particle detector

The RADMON (Radiation Monitor) was developed as a compact device with a 4-kbit SRAM particle detector and two p-FET total dose monitors. Thus it can be used as a spacecraft radiation alarm and in situ total dose monitor. This paper discusses the design and calibration of the SRAM for proton, alpha, and heavy ion detection. Upset rates for the RADMON, based on a newly developed space particle flux algorithm, are shown to vary over eight orders of magnitude. On the STRV (Space Technology Research Vehicle) the RADMON's SRAM will be used to detect trapped protons, solar flares, and cosmic rays and to evaluate our ability to predict space results from ground tests.

Buehler, Martin↗

STRV RADMON: An Integrated High-Energy Particle Detector

The RADMON (Radiation Monitor) was developed as a compact device with a 4-kbit SRAM particle detector and two p-FET total dose monitors. Thus it can be used as a spacecraft radiation alarm and in situ total dose monitor. This paper discusses the design and calibration of the SRAM for proton, alpha, and heavy ion detection. Upset rates for the RADMON, based on a newly developed space particle flux algorithm, are shown to vary over eight orders of magnitude.

RADMON↗

Improved Constraints for the XUV Luminosity Evolution of Trappist-1

We re-examine the XUV luminosity evolution of TRAPPIST-1 utilizing new observational constraints of the current stellar parameters (XUV and bolometric luminosity) from multi-epoch X-ray/UV photometry. Following the formalism presented on Fleming et al. (2020), we infer that TRAPPIST-1maintained a saturated XUV luminosity, relative to the bolometric luminosity, of log10(LXUV/Lbol)=−3.03+0.25−0.23at early times for a period of tsat= 3.14+2.22−1.46Gyr. After the saturation phase, we find LXUV decayed over time by an exponential rate ofβXUV=−1.17+0.27−0.28. Compared to our inferred age of the system, age = 7.96+1.78−1.87Gyr, our result for tsat suggests that there is only a∼4% chance thatTRAPPIST-1 still remains in the saturated phase today, which is significantly lower than the previous estimate of 40%. Despite this reduction in tsat, our results remain consistent in the conclusion that the TRAPPIST-1 planets likely received an extreme amount XUV energy—an estimated integrated XUV energy of∼1030−1032erg over the star’s lifetime—that is∼15% lower than the original result.

Stellar evolution↗

Urban Combined Heat and Power with Integrated Renewables and Energy Storage

District energy systems efficiently provide thermal energy to multiple buildings and facilities through a network of shared infrastructure. Frequently, district energy systems are centered around combined heat and power (CHP) plants that generate electricity as well as heating and cooling to the local buildings. By providing both electricity and thermal energy from a single fuel source and central location, these systems use less fuel, decrease energy and operational costs, and reduce the need for heating and cooling equipment in individual buildings.

EMS, CHP, GWU↗

Mission Applicability and Benefits of Thin-Film Integrated Power Generation and Energy Storage

This paper discusses the space mission applicability and benefits of a thin-film integrated power generation and energy storage device, i.e., an "Integrated Power Source" or IPS. The characteristics of an IPS that combines thin-film photovoltaic power generation with thin-film energy storage are described. Mission concepts for a thin-film IPS as a spacecraft main electrical power system, as a decentralized or distributed power source and as an uninterruptible power supply are discussed. For two specific missions, preliminary sizing of an IPS as a main power system is performed and benefits are assessed. IPS developmental challenges that need to be overcome in order to realize the benefits of an IPS are examined. Based on this preliminary assessment, it is concluded that the most likely and beneficial application of an IPS will be as the main power system on a very small "nanosatellite," or in specialized applications serving as a decentralized or distributed power source or uninterruptible power supply.

Hoffman, David J.↗

Mission Applicability and Benefits of Thin-Film Integrated Power Generation and Energy Storage

This paper discusses the space mission applicability and benefits of a thin-film integrated power generation and energy storage device, i.e., an "Integrated Power Source" or IPS. The characteristics of an IPS that combines thin-film photo-voltaic power generation with thin-film energy storage are described. Mission concepts for a thin-film IPS as a spacecraft main electrical power system, as a decentralized or distributed power source and as an uninterruptible power supply are discussed. For two specific missions, preliminary sizing of an IPS as a main power system is performed and benefits are assessed. IPS developmental challenges that need to be overcome in order to realize the benefits of an IPS are examined. Based on this preliminary assessment, it is concluded that the most likely and beneficial application of an IPS will be as the main power system on a very small "nanosatellite," or in specialized applications serving as a decentralized or distributed power source or uninterruptible power supply.

Hoffman, David↗