Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “Energy - Storage”

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.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 145 records · Page 8
All sourcesNASA NTRSDOE OSTI
DOE OSTI2013

Note: Characterization of a high-photon-energy X-ray imager

The Bragg angle, rocking curve, and reflection efficiency of a quartz crystal x-ray imager (Miller indices 234) were measured at photon energy of 15.6909 keV, corresponding to the K{sub α2} line of Zr, using the X15A beamline at the National Synchrotron Light Source at Brookhaven National Laboratory. One flat and three spherically curved samples were tested. The peak reflectivity of the best-performing crystal was determined to be (3.6 ± 0.7) × 10{sup −4} with a rocking-curve full width at half maximum of 0.09°. The Zr K{sub α2} emission was imaged from a hot Zr plasma generated by a 10-J multiterawatt laser.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2015

The contribution of low-energy protons to the total on-orbit SEU rate

Low- and high-energy proton experimental data and error rate predictions are presented for many bulk Si and SOI circuits from the 20-90 nm technology nodes to quantify how much low-energy protons (LEPs) can contribute to the total on-orbit single-event upset (SEU) rate. Every effort was made to predict LEP error rates that are conservatively high; even secondary protons generated in the spacecraft shielding have been included in the analysis. Across all the environments and circuits investigated, and when operating within 10% of the nominal operating voltage, LEPs were found to increase the total SEU rate to up to 4.3 times as high as it would have been in the absence of LEPs. Therefore, the best approach to account for LEP effects may be to calculate the total error rate from high-energy protons and heavy ions, and then multiply it by a safety margin of 5. If that error rate can be tolerated then our findings suggest that it is justified to waive LEP tests in certain situations. Trends were observed in the LEP angular responses of the circuits tested. As a result, grazing angles were the worst case for the SOI circuits, whereas the worst-case angle was at or near normal incidence for the bulk circuits.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2018

Development of Fleet Energy Savings Evaluation Tools for Smart Mobility: Smart Vehicle Energy Technology (SVET) Model for Passenger Fleets and Freight Fleet Level Energy Estimation Tool (FFLEET) for Freight Fleets

As part of the U.S. Department of Energy’s (DOE) Systems and Modeling for Accelerated Research in Transportation (SMART) Mobility Initiative, the Oak Ridge National Laboratory (ORNL) led a study to develop web-based tools intended to enable vehicle fleet operators, including both passenger and freight fleets, to quantify the energy savings achievable by implementing advanced transportation technologies. By developing a profile of a fleet’s existing vehicle inventory and providing data about how and where the vehicles are driven, fuel consumption can be calculated for the entire fleet and users can perform “what if” scenarios to evaluate the energy savings that can be realized when replacing existing vehicles and implementing new technologies.

33 ADVANCED PROPULSION SYSTEMS↗
DOE OSTI2020

Resilient Cooperative Voltage Control for Distribution Network with High Penetration Distributed Energy Resources

Here, this paper considers the problem of designing a resilient distributed voltage control algorithm for distribution systems with high penetration of distributed energy resources in the presence of an unknown cyber-attack. The purpose of the attack is to force the system to violate the operating voltage limit by intercepting its communication channels and inserting exogenous signals to perturb and/or modify the information being exchanged. We first review the cooperative voltage control proposed in our previous work and provide a new stability analysis for it. Next, we present a resilient cooperative voltage control algorithm by introducing a virtual system interconnected with the original system such that the voltage can be maintained within the operational limit under unknown attacks. The resiliency of the proposed algorithm is demonstrated via simulations on the IEEE 8500-node system when subjected to an attack which consists of corrupting the data being exchanged in the communication network between two generation units.

cooperative control↗
DOE OSTI2016

Galaxies in X-Ray Selected Clusters and Groups in Dark Energy Survey Data. I. Stellar Mass Growth of Bright Central Galaxies Since z ~ 1.2

Using the science verification data of the Dark Energy Survey for a new sample of 106 X-ray selected clusters and groups, we study the stellar mass growth of bright central galaxies (BCGs) since redshift z ~ 1.2. Compared with the expectation in a semi-analytical model applied to the Millennium Simulation, the observed BCGs become under-massive/under-luminous with decreasing redshift. Here, we incorporate the uncertainties associated with cluster mass, redshift, and BCG stellar mass measurements into an analysis of a redshift-dependent BCG-cluster mass relation, $m_*$ $∝ \huge{(}$$\frac{M_{200}}{1.5x10^{14}M_⊙}\huge{)}$$^{0.24±0.08}$ $(1 + z)$$^{-0.19±0.34}$, and compare the observed relation to the model prediction. We estimate the average growth rate since z = 1.0 for BCGs hosted by clusters of M 200,z = 10 13.8 M ⊙ ; at z = 1.0: m * , BCG appears to have grown by 0.13 ± 0.11 dex, in tension at the ~2.5σ significance level with the 0.40 dex growth rate expected from the semi-analytic model. We show that the build-up of extended intracluster light after z = 1.0 may alleviate this tension in BCG growth rates.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2018

Energy security role of biofuels in evolving liquid fuel markets

In this work, we explore the role of biofuels in mitigating the negative impacts of oil supply shocks on fuel markets under a range of oil price trajectories and biofuel blending mandate levels. Using a partial equilibrium model of US biofuels production and petroleum fuels trade, we discuss the adjustments in light-duty vehicle fuel mix, fuel prices, and renewable identification number (RIN) prices following each shock as well as the distribution of shock costs across market participants. Ethanol is used as both a complement (blend component in E10) and a substitute (in E15 and E85 blends) to gasoline. Results show that, during oil supply shocks, the role of ethanol as a substitute dominates and allows some mitigation of the shock. As US petroleum imports decrease with growing US oil production, the net economic welfare effect of sudden oil price changes and the energy security role of biofuels becomes less clear than it has been in the past. Although fuel consumers lose when oil price increases due to an external shock, domestic fuel producers gain. In some cases, depending on import share and supply and demand elasticities, we show that the gain to producers could more than offset consumer losses. However, in most cases evaluated here, sudden oil-price increases remain costly.

09 BIOMASS FUELS↗
DOE OSTI2021

An Open-Source Virtual Testbed for a Real Net-Zero Energy Community

Net zero energy communities (NZECs) are critical to ensure sustainability and resilience of modernized power systems. System modeling helps overcome technical challenges in designing and operating NZECs. In this paper, we present the modeling work based on a real NZEC. Two sets of models are developed: higher-fidelity physics-based models considering the interaction between subsystems of the studied NZEC and capturing fast-dynamics; and lower-fidelity data-driven models requiring less resource to establish and/or run. All models are validated against measurements from this real NZEC. In addition, we create a simulation framework which streamlines the processes for simulation and thus allows using developed models to form a virtual testbed. To demonstrate the usage of the virtual testbed, a case study is conducted where a building-to-grid integration control is evaluated via simulation. The evaluation results suggest that the tested control significantly smooths the power draw of the studied community and doesn’t sacrifice the thermal comfort to a great extent.

Huang, Sen↗
DOE OSTI2016

A unified relation for the solid-liquid interface free energy of pure FCC, BCC, and HCP metals

We study correlations between the solid-liquid interface (SLI) free energy and bulk material properties (melting temperature, latent heat, and liquid structure) through the determination of SLI free energies for bcc and hcp metals from molecular dynamics (MD) simulation. Values obtained for the bcc metals in this study were compared to values predicted by the Turnbull, Laird, and Ewing relations on the basis of previously published MD simulation data. We found that of these three empirical relations, the Ewing relation better describes the MD simulation data. Moreover, whereas the original Ewing relation contains two constants for a particular crystal structure, we found that the first coefficient in the Ewing relation does not depend on crystal structure, taking a common value for all three phases, at least for the class of the systems described by embedded-atom method potentials (which are considered to provide a reasonable approximation for metals).

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2022

Mooring Load Monitoring of a Wave Energy Converter Using a Self-Synchronizing Underwater Acoustic Network

A self-synchronizing underwater acoustic network, designed for remote monitoring of mooring loads in Wave Energy Converters (WEC), has been developed and tested. This network uses Time Division Multiple Access and operates self-contained with the ability for users to remotely transmit commands to the network as needed. Each node is a self-contained unit, consisting of a protocol adaptor board, an underwater acoustic modem and a battery pack. A node can be connected to a load cell, to a topside user or to the WEC. Every node is swapable. The protocol adaptor board, named Protocol Adaptor for Digital LOad Cell (PADLOC) supports a variety of digital load cell message formats (CAN, MODBUS, custom ASCII) and underwater acoustic modem serial formats. PADLOC enables topside users to connect to separate load cells through a user-specific command.

acoustic↗
DOE OSTI2017

Effects of Fuel Laminar Flame Speed Compared to Engine Tumble Ratio, Ignition Energy, and Injection Strategy on Lean and EGR Dilute Spark Ignition Combustion

Previously we show that fuels with higher laminar flame speed also have increased tolerance to EGR dilution. In this work, the effects of fuel laminar flame speed on both lean and EGR dilute spark ignition combustion stability were examined. Fuels blends of pure components (iso-octane, n-heptane, toluene, ethanol, and methanol) were derived at two levels of laminar flame speed. Each fuel blend was tested in a single-cylinder spark-ignition engine under both lean-out and EGR dilution sweeps until the coefficient of variance of indicated mean effective pressure increased above thresholds of 3% and 5%. The relative importance of fuel laminar flame speed to changes to engine design parameters (spark ignition energy, tumble ratio, and port vs. direct injection) was also assessed. Our results showed that fuel laminar flame speed can have as big an effect on lean or EGR dilute engine operation as engine design parameters, with the largest effects seen during EGR dilute operation and when changes were made to cylinder charge motion.

10 SYNTHETIC FUELS↗
DOE OSTI2015

Energy Transition Initiative: Island Energy Snapshot - San Andres and Providencia (Fact Sheet); NREL(National Renewable Energy Laboratory)

This profile provides a snapshot of the energy landscape of the Archipelago of San Andres, Providencia, and Santa Catalina (unpopulated), also known as San Andres and Providencia, which is equidistant between Costa Rica and Jamaica and 775 kilometers northwest of Colombia. The archipelago is part of Colombia, though Nicaragua has also laid claim to it.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗