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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 487 records · Page 27
All sourcesNASA NTRSDOE OSTI
DOE OSTI2018

A simple model of the effect of ocean ventilation on ocean heat uptake

Presentation includes slides on Earth System Models vs. Simple Climate Models; A Popular SCM: Energy Balance Model of Anomalies; On calibrating against one ESM experiment, the SCM correctly captures that ESM's surface warming response with other forcings; Multi-Model Analysis: Multiple ESMs, Single SCM; Posterior Distributions of ECS; However In Excess of 90% of TOA Energy Imbalance is Sequestered in the World Oceans; Heat Storage in the Two Layer Model; Heat Storage in the Two Layer Model; Including TOA Rad. Imbalance and Ocean Heat in Calibration Improves Repr., but Significant Errors Persist; Improved Vertical Resolution Does Not Fix Problem; A Series of Expts. Confirms That Anomaly-Diffusing Models Cannot Properly Represent Ocean Heat Uptake; Physics of the Thermocline; Outcropping Isopycnals and Horizontally-Averaged Layers; Local interactions between outcropping isopycnals leads to non-local interactions between horizontally-averaged layers; Both Surface Warming and Ocean Heat are Well Represented With Just 4 Layers; A Series of Expts. Confirms That When Non-Local Interactions are Allowed, the SCMs Can Represent Both Surface Warming and Ocean Heat Uptake; and Summary and Conclusions.

58 GEOSCIENCES↗
DOE OSTI2018

Evaluating Moisture Control of Variable-Capacity Heat Pumps in Mechanically Ventilated, Low-Load Homes in Climate Zone 2A

Low-load homes can present a challenge when selecting appropriate space-conditioning equipment. Conventional, fixed-capacity heating and cooling equipment is often oversized for small homes, causing increased first costs and operating costs. This report evaluates the performance of variable-capacity comfort systems, with a focus on inverter-driven, variable-capacity systems, as well as proposed system enhancements.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2018

Prototype Ceramic High Efficiency Particulate Air Filter Testing and Filter Media Development for Nuclear Facility Ventilation

This report summarizes recent and past related Ceramic HEPA Filter activity for this NNSA NSR&D project and on-going plans for FY18 and FY19 work as presently planned. Prior work has evaluated concepts for a ceramic HEPA filter including ceramic support materials, filter media including electrospun filter media, and metal housing designs to accommodate the conservative temperature performance target of up to 500°C. This has been supported by modelling efforts discussed with nuclear facility system engineers and their management. The temperature and time-at-temperature are based on conservative, bounding temperatures from fire analysis presented as a draft EFCOG best practice paper for nuclear facility safety analysis. The overall goal is to improve safety of DOE nuclear facilities during fire scenarios by developing improved filtration technology including increasing performance while reducing pressure drop. Ceramic filtration technology can provide robust, passive mitigation against radiological releases. The goal of the ceramic HEPA filter is to provide a robust HEPA filter that provides increased temperature performance in an equivalent form factor (size and shape) that is similar to existing conventional HEPA filters used in facilities. Once qualified for use in facilities, the benefit of a ceramic HEPA filters could simplify and reduce safety and support system costs, as well as considerably lower life-cycle costs. Installation, monitoring, and maintenance of active fire suppression systems, as well as other related systems, are a considerable on-going cost to nuclear facilities. Reducing the level of dependence on Safety Class and Safety Significant fire alarm and fire suppression systems could allow significant cost savings. At present we are continuing research and development efforts towards the goal of a ceramic filter design, including improved ceramic filter media, that could reduce total operation cost for facilities utilizing HEPA filters.

42 ENGINEERING↗
DOE OSTI2018

NSRD-12, Novel Mini-Tubular HEPA Media for Nuclear Facility Ventilation Systems

The overall goal is to improve safety of DOE nuclear facilities during fire scenarios by developing improved filtration technology, increasing performance while reducing pressure drop. Ceramic filtration technology can provide robust, passive mitigation against radiological releases.The primary objective of this report is to demonstrate that mini-tubular ceramic (MTC) media can reduce pressure drop across a filter compared to flow through a membrane. A secondary objective is to obtain a baseline filtration efficiency measurement. Reducing pressure drop across a filter through MTC design can be combined with nanofiber technology to improve filter performance. Developing MTC media can also solve processing challenges associated with manufacturing ceramic nanofiber membranes and coatings by electrospinning. This work will support developing specifications for industry codes and standards such as ASME AG-1, Subsection FO, Ceramic Filters.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2019

Mercury Dispersion Modeling and Purge Ventilation Stack Height Determination for Tank 31H

The SRNL Atmospheric Technologies Group performed an analysis of mercury emissions from the H-Tank Farm Tank 31-H to assess worst case 15-minute, 1-hour and 8-hour average concentrations and evaluate whether the ACIGH Short-Term Exposure Limit (STEL), PAC (Protection Action Criteria), or Threshold Limit Value (TLV) levels for mercury are exceeded. This analysis was also used to establish a minimum stack height at which ambient mercury concentration would not exceed the regulatory limits. The American Meteorological Society/Environmental Protection Agency Regulatory Model (AERMOD) was used as the dispersion modeling tool for this analysis. The PAC standard is not exceeded for any of the stack heights, or release scenario. A 92 ft stack for the 25 mg/m 3 modeling scenario and 95 ft for the 50 mg/m 3 are necessary to prevent all exceedances at all receptors. If the highest receptor on the Evaporator West Stack Platform is excluded from the domain, then the maximum heights are 35 ft and 52 ft for the 25 mg/m 3 and the 50 mg/m 3 modeling scenarios, respectively.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2019

Prototype Ceramic HEPA Filter Testing and Filter Media Research and Development for Nuclear Facility Ventilation

This is a brief summary of recent and past Ceramic HEPA Filter research and development activities under an NNSA NSR&D funded project and describes on-going plans for FY19 work as presently planned. Prior work has evaluated concepts for a ceramic HEPA filter including ceramic support materials, filter media including electrospun filter media, and metal housing designs to accommodate the conservative temperature performance target of up to 500°C. This has been supported by modelling efforts discussed with nuclear facility system engineers and their management. The temperature and time-attemperature are based on conservative, bounding temperatures from fire analysis presented as an EFCOG best practice paper for nuclear facility safety analysis. The overall goal is to improve safety of DOE nuclear facilities during fire scenarios by developing improved filtration technology including increasing temperature performance while maintaining acceptable filter pressure drop. Ceramic filtration technology can provide robust, passive mitigation against radiological releases. The goal of the ceramic HEPA filter is to provide a HEPA filter that provides increased temperature performance in an equivalent form factor (size and shape) that is similar to existing conventional HEPA filters used in facilities. Once development is complete and qualified for use in facilities, ceramic HEPA filters could simplify and reduce safety and support system costs, as well as lower life-cycle costs. Installation, monitoring, and maintenance of active fire suppression systems, as well as other related systems, are a considerable on-going cost to nuclear facilities. Reducing the level of dependence on Safety Class and Safety Significant fire alarm and fire suppression systems could allow significant cost savings. At present we are continuing research and development efforts towards the goal of a ceramic filter design, including improved ceramic filter media, that could reduce total operation cost for facilities utilizing HEPA filters.

36 MATERIALS SCIENCE↗
DOE OSTI2019

Prototype Ceramic HEPA Filter Testing and Filter Media Research and Development for Nuclear Facility Ventilation

This is a brief summary of recent and past Ceramic HEPA Filter research and development activities under an NNSA NSR&D funded project and describes on-going plans for FY19 work as presently planned. Prior work has evaluated concepts for a ceramic HEPA filter including ceramic support materials, filter media including electrospun filter media, and metal housing designs to accommodate the conservative temperature performance target of up to 500°C. This has been supported by modelling efforts discussed with nuclear facility system engineers and their management. The temperature and time-at-temperature are based on conservative, bounding temperatures from fire analysis presented as an EFCOG best practice paper for nuclear facility safety analysis. The overall goal is to improve safety of DOE nuclear facilities during fire scenarios by developing improved filtration technology including increasing temperature performance while maintaining acceptable filter pressure drop. Ceramic filtration technology can provide robust, passive mitigation against radiological releases. The goal of the ceramic HEPA filter is to provide a HEPA filter that provides increased temperature performance in an equivalent form factor (size and shape) that is similar to existing conventional HEPA filters used in facilities. Once development is complete and qualified for use in facilities, ceramic HEPA filters could simplify and reduce safety and support system costs, as well as lower life-cycle costs. Installation, monitoring, and maintenance of active fire suppression systems, as well as other related systems, are a considerable on-going cost to nuclear facilities. Reducing the level of dependence on Safety Class and Safety Significant fire alarm and fire suppression systems could allow significant cost savings, while maintaining safety. At present we are continuing research and development efforts towards the goal of a ceramic filter design, including improved ceramic filter media, that could reduce total operation cost for facilities utilizing HEPA filters.

36 MATERIALS SCIENCE↗
DOE OSTI2019

Mercury Dispersion Modeling and Purge Ventilation Stack Height Determination for Tank 35H Bulk Sludge Removal

The SRNL Atmospheric Technologies Group performed an analysis of mercury emissions from the H-Tank Farm Tank 35-H to assess worst case 15-minute, 1-hour and 8-hour average concentrations and evaluate whether the ACIGH Short-Term Exposure Limit (STEL), PAC (Protection Action Criteria), or Threshold Limit Value (TLV) levels for mercury are exceeded. This analysis was also used to establish a minimum stack height at which ambient mercury concentration would not exceed the regulatory limits. The American Meteorological Society/Environmental Protection Agency Regulatory Model (AERMOD) was used as the dispersion modeling tool for this analysis. The PAC standard is not exceeded for any of the stack heights, or release scenario. A 100 ft stack for the 50 mg/m 3 modeling scenario and 110 ft for the 100 mg/m3 are necessary to prevent all exceedances at all receptors. If the highest receptor on the Evaporator West Stack Platform is excluded from the domain, then the maximum heights are 65 ft and 105 ft for the 50 mg/m 3 and the 100 mg/m 3 modeling scenarios, respectively.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2019

Mercury Dispersion Modeling and Purge Ventilation Stack Height Determination for SDUs

The SRNL Atmospheric Technologies Group performed an analysis to determine the minimum stack height necessary to avoid exceedance of the ACGIH (American Conference of Governmental Industrial Hygienists) 15-minute Short-Term Exposure Limit (STEL) and 8-hour Time Weighted Average (TWA) ambient standards for worst case hazardous chemical emissions from the Z-Area Mega SDUs. The American Meteorological Society/Environmental Protection Agency Regulatory Model (AERMOD) was used as the dispersion modeling tool for this analysis. Receptors were placed to represent the breathing level concentrations that workers might have, placed 6-ft above the working surface (ground or SDU tank surface). Based on the analysis conducted, the minimum SDU exhaust release height to avoid exceeding STEL and TWA is 6 feet above the SDU roof level for flow rates between 300 and 1200 cfm. The configuration of Mega SDUs, while large structures, do not produce an aerodynamic wake that impacts the stack releases and causes exceedances to the worker exposure limits.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2020

PMK 1000 cone-socket ventilator fittings force testing to ISO 5356-1:2015 Standard

This memo summarizes the results of verification tests on a cone-socket fitting to the ISO 5356-1:2015 standard, annexes B and F. The components were found to meet requirements holding 50N tensile force and more than 35 N-cm of torque for 10 seconds without separating at 35°C with a fresh socket. Humidity control was unavailable; consequently, humidity was significantly lower than the values in the ISO standard. Several repeat tests of the fitting with force, torque, and time excursions give us confidence that the fittings perform suitably to the ISO standard. Force overload tests suggest that the samples will disengage under tension at around 69 N, while torque overload tests under a force of 50 N will fail at 79 N-cm of torque. If repeated tests are performed on the same component, the socket can deform and lead to the connection failing the standard requirements. However, such failures only occur with repeated testing, and the gripping of such units can be modified so that they pass the standard. This observation demonstrates that socket gripping is responsible for those failures and would not be a problem in application.

42 ENGINEERING↗
DOE OSTI2021

Modeling Environmental Effects on Ventilated Spent Fuel Storage Systems

This report describes newly developed external environment wind effects models of spent nuclear fuel (SNF) dry storage systems. The primary purpose of these wind effects models is to better understand particle deposition on SNF canisters in the context of chloride-induced stress corrosion cracking. The goal of this effort is to further the understanding and improve the wind effects model of the Nuclear Horizontal Modular Storage (NUHOMS ® ) Advanced Horizontal Storage Module–High Seismic (AHSM-HS) storage system in support of the planned Canister Deposition Field Demonstration (CDFD) project (Durbin et al. 2021, Suffield et al. 2021). The steps in this wind effects investigation begin with a validation case of comparing experimental data with a STAR-CCM+ computational fluid dynamics (CFD) model of the Belowground Vertical Dry Cask Simulator (BVDCS) with the external environment explicitly modeled. Next, a test case is performed with the AHSM-HS models comparing solar-loading strategies for a standalone and wind effects model in STAR-CCM+ and a standalone model in ANSYS Mechanical Parametric Design Language (APDL). The final portion of this study compares results of the validation exercise with applications of wind effects models for two horizontal storage systems, a site specific NUHOMS ® horizontal storage module and a NUHOMS ® AHSM-HS.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2021

Ultraviolet Germicidal Irradiation for Heating, Ventilation, and Air Conditioning: Literature Review

Ultraviolet germicidal irradiation (UVGI) remains the only ASHRAE-recognized technology for the effective disinfection of air and surfaces, yet the technology still faces barriers to adoption. Even so, there is a growing body of literature on the subject, somewhat due the possibilities that a technology that can disinfect from a distance presents but also because the technology has been known for some time. Recent interest in the technology has been driven by the COVID-19 pandemic, increasing the rate of growth of the literature. This document attempts to provide an overview of the technology and map out the various important parts of the literature, including potential sources of literature.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2024

Charlo Junior High Heating, Ventilation, and Air Conditioning (HVAC) Upgrade and Energy Improvements

The Charlo School District 7J is located at 404 1st Ave West, in Charlo, Montana. The District has 55,778 ft² of facility space serving students from grades K through 12 in the Western Montana community of Charlo, within the Flathead Indian Reservation. The campus is made up of four primary buildings which are the elementary building, administration and high school, a junior high wing with a shop, and the gymnasium/multipurpose building. This project will focus on the needs of the Junior High Facility.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2025

Heating Ventilation Air-Conditioning (HVAC) System Analysis and Optimization for Revit with the OpenStudio Analytical Framework (CRADA Final Report)

This project proposes to integrate the NREL-developed OpenStudio (OS) and its accompanying Analytical Framework (OSAF) into Autodesk’s (ADSK’s) market leading suite of building information modeling (BIM) tools. As a result, BIM users will gain access to advanced (but user-friendly) building energy modeling (BEM), calibration, and design optimization capabilities. Following integration, the BIM software will automatically generate a consistent OS-based BEM model, allowing users to develop projects in an integrated manner, moving back and forth between architectural and engineering perspectives without redundancy or data loss, saving time and effort.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗