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Effectiveness of Versalink 143 on Improving Shock Survival of Encapsulated Electronics

Limmer, Joel; Curtis, Shane

In the past, test-vehicle-mounted instrumentation modules that record sensor data during shock and vibration events have been coated with a polymer isolation layer to enhance survivability. This study uses finite element modeling to evaluate the effectiveness of the isolation material Versalink 143 on reducing stress in an instrumentation module. The modeling shows that while the isolation layer does attenuate stress due to high frequency shock and vibration, it also amplifies stress due to lower frequency shock and vibration. Thicker layers tend to attenuate high frequency stress more and amplify low frequency stress less. In addition, at higher test temperatures thermal expansion of the isolation layer can cause static stress in the module far greater than the stress due to shock, depending on how the module is constrained within the test vehicle. When designing and implementing vehicle- mounted instrumentation modules, the expected input shock spectrum, mounting constraints, and static effects of temperature must be carefully considered.

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TYPE SAND Report YEAR 2021
DOIOSTI

Electrical Energy Storage Data Submission Guidelines, Version 2

Rosewater, David; Preger, Yuliya; Mueller, Jacob A.; Atcitty, Stanley; Willard, Steve; Smith, Morgan; Thompson, Joe; Long, Dirk

Energy storage technologies are positioned to play a substantial role in power delivery systems. They have the potential to serve as an effective new resource to maintain reliability and allow for increased penetration of renewable energy. However, because of their relative infancy, there is a lack of knowledge about how these resources truly operate over time. A data analysis can help ascertain the operational and performance characteristics of these emerging technologies. Rigorous testing and a data analysis are important for all stakeholders to ensure a safe, reliable system that performs predictably on a macro level. Standardizing testing and analysis approaches to verify the performance of energy storage devices, equipment, and systems when integrating them into the grid will improve the understanding and benefit of energy storage over time from technical and economic vantage points. Demonstrating the life-cycle value and capabilities of energy storage systems begins with the data that the provider supplies for the analysis. After a review of energy storage data received from several providers, some of these data have clearly shown to be inconsistent and incomplete, raising the question of their efficacy for a robust analysis. This report reviews and proposes general guidelines, such as sampling rates and data points, that providers must supply for a robust data analysis to take place. Consistent guidelines are the basis of a proper protocol and ensuing standards to (1) reduce the time that it takes for data to reach those who are providing the analysis; (2) allow them to better understand the energy storage installations; and (3) enable them to provide a high-quality analysis of the installations. The report is intended to serve as a starting point for what data points should be provided when monitoring. Readers are encouraged to use the guidance in the report to develop specifications for new systems, as well as enhance current efforts to ensure optimal storage performance. As battery technologies continue to advance and the industry expands, the report will be updated to remain current.

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TYPE SAND Report YEAR 2021
DOIOSTI

Noninvasive THz-TDS measurements of plasma bounded and optically shielded by Hall thruster wall material

Plasma Sources Science and Technology

Brown, Nathan P.

We experimentally demonstrate the capability of terahertz time-domain spectroscopy (THz-TDS) to noninvasively measure the electron density and collision frequency of plasma bounded and optically shielded by Hall thruster wall material. This paper augments the standard THz-TDS plasma diagnostic theory to account for plasma boundaries, presents THz optical property measurements of three different wall materials (grades M, M26, and HP boron nitride composite), and provides electron density and collision frequency measurements of an inductively coupled plasma bounded and optically shielded by each wall material. We find that the electron density measurement capability is weakly impacted by the boundaries, whereas the electron collision frequency measurement capability is strongly reduced by the boundaries. The bounded plasma electron density trends deviate substantially from those of the unbounded plasma.

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TYPE Journal Article YEAR 2021
DOIOSTIScopus

Cathodic Kinetics on Platinum and Stainless Steel in NaOH Environments

Journal of the Electrochemical Society

Katona, Ryan M.; Carpenter, J.; Schindelholz, E.J.; Schaller, Rebecca S.; Kelly, R.G.

During typical atmospheric conditions, cathodic reduction reactions produce hydroxyl ions increasing the pH in the cathodic region. Therefore, cathodic reduction reactions are investigated on platinum and stainless steel 304 L (SS304L) in NaOH solutions ranging in pH from 13.6 to 16.5. It was found that in solution pHs less than 16.5 the cathodic reduction reaction on Pt and SS304L was ORR with an electron transfer number less than two due to superoxide formation as an intermediate. Increasing pH decreased the number of electrons transferred. At a pH of 16.5, the cathodic reduction reaction on SS304L is no longer ORR and the cathodic current on the surface of the alloy is due to oxide reduction occurring on the surface as indicated by the creation of multi-component Pourbaix diagrams. The results of this study have important implications for predicting corrosion in atmospheric environments.

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TYPE Journal Article YEAR 2021
DOIOSTIScopus

Silicon Consortium Project: No-Go on Moir Interferometry for Measuring SEI Strain as a Probe for Calendar Life Testing

Mcbrayer, Josefine D.; Serkland, Darwin K.; Fenton, Kyle R.; Apblett, Christopher A.; Minteer, Shelley; Harrison, Katharine L.

Silicon is a promising candidate as a next generation anode to replace or complement graphite electrodes due to its high energy density and low lithiation potential. When silicon is lithiated, it experiences over 300% expansion which stresses the silicon as well as its solid electrolyte interphase (SEI) leading to poor performance. The use of nano-sized silicon has helped to mitigate volume expansion and stress in the silicon, yet the silicon SEI is still both mechanically and chemically unstable. Identifying the mechanical failure mechanism of the SEI will help enhance calendar and cycle life performance through improved SEI design. In situ moiré interferometry was investigated to try and track the in-plane strain in the SEI and silicon electrode for this purpose. Moiré can detect on the order of 10 nm changes in displacement and is therefore a useful tool in the measurement of strain. As the sample undergoes small deformations, large changes in the moiré fringe allow for measurements of displacement below the diffraction limit of light. Figure 1a shows how the moiré fringe changes as the sample grating deforms. As the sample contracts or expands, the frequency of the moiré fringe changes, and this change is proportional to the strain in the sample.

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TYPE Other Report YEAR 2021
DOIOSTI

Hazardous Chemical Inventory Guidelines, Purpose, and Process

Cudney-Black, Jane; Fritz, Hugh; Garcia, Matthew; Robinson, Sean; Ross, Tonya S.A.; Castillo, Brian

The Environment, Safety, and Health Planning department at Sandia National Laboratories is interested in the purchase and storage of chemicals and their potential impact following an uncontrolled release. The large number of projects conducted at SNL make tracking every chemical purchase impractical; therefore, attention is focused on hazardous substances purchased in large quantities. Chemicals and quantities of concern are determined through regulatory guidelines; e.g., the OSHA Process Safety Management list, the EPA Risk Management Plan list, and the Department of Energy Subcommittee on Consequence Assessment and Protective Actions Emergency Response Planning Guidelines. Based on these regulations, a list of chemicals with quantities of concern was created using the Aerial Locations of Hazardous Atmospheres (ALOHA) and SCREEN View chemical dispersion modelling software. The nature of this report does not draw conclusions, rather it documents the logic for a chemicals of concern list to ensure compliance with various regulations and form the basis for monitoring chemicals that may affect hazard classification. Hazardous Chemical Inventory Guidelines, Purpose, and Process 4 This page left blank.

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TYPE SAND Report YEAR 2021
DOIOSTI

Assess and Benchmark Magneto-Inertial Fusion (MIF) Scaling. Final Technical Report for the SNL/Rochester ALPHA Follow-on Project

Peterson, K.J.

This project was a follow-on to the Sandia National Laboratories (SNL) and the Laboratory for Laser Energetics (LLE) ARPA-E ALPHA project entitled “Demonstrating Fuel Magnetization and Laser Heating Tools for Low-Cost Fusion Energy”. The primary purpose of this follow-on project was to obtain additional data at the OMEGA facility to help better understand how MagLIF, a platform that has already demonstrated the scientific viability of magneto-inertial fusion, scales across a factor of 1000 in driver energy. A secondary aspect of this project was to extend simulations and analysis at SNL to cover a wider magneto-inertial fusion (MIF) parameter space and test scaling of those models across this wide range of input energies and conditions of the target. This work was successful in improving understanding of how key physics elements of MIF scales and improves confidence in setting requirements for fusion gain with larger drivers. The OMEGA experiments at the smaller scale verified the hypothesis that preheating the fuel plays a significant role in introducing wall contaminants that mix into the fuel and significantly degrade fusion performance. This contamination not only impacts target performance but the optimal input conditions for the target. However, analysis at the Z-scale showed that target performance at high preheat levels is limited by the Nernst effect, which advects magnetic flux from the hot spot, reducing magnetic insulation and consequently reduces the temperature of the fuel. The combination of MagLIF experiments at the disparate scales of OMEGA and Z along with a multiscale 3D simulation analysis has led to new insight into the physical mechanisms responsible for limiting target performance and provides important benchmarks to assess target scaling more generally for MIF schemes. Finally, in addition to the MagLIF related work, a semi-analytic model of liner driven Field Reversed Configuration (FRC) was developed that predicts the fusion gain for such systems. This model was also validated with 2D radiation magneto-hydrodynamic simulations and predicts that fusion gains of near unity could be driven by the Z machine.

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TYPE Other Report YEAR 2021
DOIOSTI
Results 11401–11600 of 99,299
Results 11401–11600 of 99,299