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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 73 records · Page 4
All sourcesNASA NTRSDOE OSTI
DOE OSTI2023

Effects of Accident Thermal Loading on In-Plane Shear Behavior of Steel-Plate Composite Walls

Structural walls in safety-related nuclear facilities are required to be designed for seismic and accident thermal (due to postulated high-energy pipe break events) loading combination. Current U.S. and international codes provide limited guidance for analysis and design of walls for this loading combination. This paper describes the experimental results and observations from tests conducted on a laboratory-scale (1:4 to 1:5) test unit representing steel-plate composite (SC) walls subjected to combined in-plane (seismic) and accident thermal loading. The test unit was subjected to surface temperatures of up to 450°F in combination with cyclic in-plane loading. Results of similar experiments recently conducted in Japan are also summarized (with surface temperatures up to 570°F). Surface heating combined with the low thermal conductivity and high specific heat of concrete resulted in nonlinear thermal gradients through the thickness of the specimens. These nonlinear thermal gradients and the associated self- or internal restraint led to extensive concrete cracking. This concrete cracking reduced the initial and secant stiffness of the specimens. The initial stiffness of the heated specimens reduced to 30 to 40% of the initial stiffness of the control (unheated) specimen. The secant stiffness of the heated specimens reduced up to 50% of the secant stiffness of the control (unheated) specimen. However, the in-plane shear strength of the heated SC specimens was still approximately 10 to 30% greater than the nominal in-plane shear strength calculated, for the limit state of steel plate von Mises yielding, using AISC N690 equations and measured material properties. Evaluation of the experimental results and observations suggests that the in-plane shear strength of SC walls subjected to typical accident surface temperatures (up to 570°F) can be estimated conservatively using the current provisions of AISC N690. The stiffness for accident thermal loading combinations can be considered to reduce from cracked composite stiffness at ambient temperature to fully cracked—that is, steel-only stiffness as the surface temperature increases up to typical accident value.

Construction & Building Technology↗
DOE OSTI2025

Portable Software Environment for Ultrahigh-Resolution ELM Development on GPUs

This paper presents our endeavors in developing the large-scale, ultra-high-resolution E3SM Land Model (uELM), specifically designed for exascale computers furnished with accelerators such as Nvidia GPUs. The uELM is a sophisticated code that substantially relies on High-Performance Computing (HPC) environments, necessitating particular machine and software configurations. To facilitate community-based uELM developments employing GPUs, we have created a portable, standalone software environment preconfigured with uELM input datasets, simulation cases, and source code. This environment, utilizing Docker, encompasses all essential code, libraries, and system software for uELM development on GPUs. It also features a functional unit test framework and an offline model testbed for comprehensive numerical experiments. From a technical perspective, the paper discusses GPU-ready container generations, uELM code management, and input data distribution across computational platforms. Lastly, the paper demonstrates the use of environment for functional unit testing, end-to-end simulation on CPUs and GPUs, and collaborative code development.

E3SM Land Model↗
DOE OSTI2017

Thermocouple Errors when Mounted on Cylindrical Surfaces in Abnormal Thermal Environments.

Mineral-insulated, metal-sheathed, Type-K thermocouples are used to measure the temperature of various items in high-temperature environments, often exceeding 1000degC (1273 K). The thermocouple wires (chromel and alumel) are protected from the harsh environments by an Inconel sheath and magnesium oxide (MgO) insulation. The sheath and insulation are required for reliable measurements. Due to the sheath and MgO insulation, the temperature registered by the thermocouple is not the temperature of the surface of interest. In some cases, the error incurred is large enough to be of concern because these data are used for model validation, and thus the uncertainties of the data need to be well documented. This report documents the error using 0.062" and 0.040" diameter Inconel sheathed, Type-K thermocouples mounted on cylindrical surfaces (inside of a shroud, outside and inside of a mock test unit). After an initial transient, the thermocouple bias errors typically range only about +-1-2% of the reading in K. After all of the uncertainty sources have been included, the total uncertainty to 95% confidence, for shroud or test unit TCs in abnormal thermal environments, is about +-2% of the reading in K, lower than the +-3% typically used for flat shrouds. Recommendations are provided in Section 6 to facilitate interpretation and use of the results. .

47 OTHER INSTRUMENTATION↗
DOE OSTI2019

Design of an experimental facility with a unit cell test section for studies of the lower plenum in prismatic high temperature gas reactors

A proposed design for a Generation IV reactor is the very-high temperature reactor (VHTR), which employs helium as the primary coolant. Although many advantages exist with this design, a number of challenges remain. One such area of concern is the turbulent mixing of non-isothermal flows in the lower plenum, where an array of coolant jets collectively mix and traverse around a series of structural support posts before exiting the core. Neighboring jets in the lower plenum could experience temperature differences as high as 300–400 K, causing potential hot streaking in the support posts. Additional problems could occur further downstream if the level of non-uniformity in the temperatures is too high (e.g, inducing thermal stresses on gas turbine blades). Therefore, it is important that adequate tools exist to predict the turbulent mixing within the VHTR lower plenum. This task remains difficult to achieve due to the complex geometry and flow physics that dictate the mixing. Various modeling approaches can only be assessed using data acquired from a carefully designed experimental facility. This paper presents details of such a facility, where high-fidelity measurements can be acquired for a scaled portion of the lower plenum defined herein as a ‘‘unit cell”, which consists of a hexagonal array of jets whose flow is directed into a test section with support posts positioned between neighboring jets, and subjected to a crossflow. Through adjusting velocity and temperature conditions at the jet inlets, different locations within the lower plenum can be experimentally simulated. System response quantities (SRQs) include both temperature and velocity measurements, captured via multiple thermocouples embedded in each post, and particle image velocimetry (PIV), respectively. These SRQs provide assessment metrics for both the momentum and energy models present in current computational solvers, and therefore the experimental facility is a valuable source for validation data. Another benefit is a more comprehensive understanding of the thermal-hydraulic loading conditions and flow physics present in the VHTR lower plenum.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2019

Chemical Looping Coal Gasification Sub-Pilot Unit Demonstration and Economic Assessment for IGCC applications (Final Report)

The Ohio State University (OSU) coal to syngas (CTS) technology is an advanced air separation process that can be applied for electricity production via an integrated gasification combined cycle (IGCC). The objective of the proposed project is to enable the OSU CLG technology for a commercially relevant demonstration by 2020. In order to accomplish this objective, small pilot scale demonstration of the CLG reactor system was performed. The small pilot test unit incorporates commercially scalable non-mechanical gas sealing and solids flow control components for extended operations of the integrated reactor system. A cumulative demonstration of greater than 100 hours was performed to confirm the reliability of the reactors (reducer and oxidizer) and non-mechanical devices in maintaining controlled solid circulation, gas sealing, and coal distribution in the reactor (reducer) as well as to confirm sustained syngas product performance. A comprehensive techno-economic analysis (TEA) of the OSU CLG process for IGCC application was conducted with the support of WorleyParsons, Ltd. (WP) and compared to the Department of Energy (DOE) baseline IGCC report. Using the data gained from the small pilot demonstration, a complete comprehensive techno-economic analysis (TEA) of the CLG process was conducted. The evaluation was used as basis to attract utilities and coal industries in Ohio. The project duration lasts 30 months (6 months of no cost extension). Ohio coal was used in the integrated CLG small pilot unit to convert to high hydrogen syngas. A demonstration of the integrated chemical looping reactor system at the 15 kW th scale accelerates technology commercialization in the near term. The 15 kWth demonstration addressed several major technology gaps, such as coal injection and distribution in the reducer, controllable solids circulation with the desired fuel to solids ratio, system pressure distribution for proper gas sealing, effects of contaminants and fuel/oxygen carrier residence time requirements. The fates of impurities, such as SO x and NO x was also investigated in unit demonstrations. WP conducted a comprehensive system TEA to optimize the OSU CLG process design for efficient electricity generation with greater than 90% CO 2 capture in IGCC applications. The conclusion of this project supports the further scale-up of the technology to a commercially applicable large pilot scale test unit for operation by 2020. More importantly, it benefits Ohio as it provides an economically competitive mean for power generation with carbon capture. Given the rise of natural gas usage and strict environmental regulations, the use of Ohio coal is expected to decrease and thus impact the coal economy in Ohio. The conclusion of this project provided way for Ohio coal to compete in the future and secure jobs in the energy sector.

01 COAL, LIGNITE, AND PEAT↗
DOE OSTI2024

Julienne v1.0.0

Julienne is a compiler-portable unit-testing framework for Fortran software projects, including those that use the parallel/accelerator-programming features of Fortran 2023. Julienne achieves portability across compilers through minimalism and isolation. The minimal design ensures that Julienne uses only features supported by the majority of Fortran compilers. The isolation through zero dependencies ensures that no other projects block Julienne from building with a particular compiler. Julienne also contains with additional services that support its unit-testing code. These include functions for manipulating strings, command lines and input/output format strings; and a user-defined collective subroutine for verifying that all processes pass a test in parallel testing. Julienne's name derives from the term for vegetables sliced into thin strings: julienne vegetables. Julienne captures the authors' most frequently used thin slice of the Veggies and Sourcery software repositories while avoiding certain compiler limitations of the those two packages.

Rouson, Damian↗
DOE OSTI2018

Advanced Control Architecture and Sensor Information Development for Process Automation, Optimization, and Imaging of Chemical Looping Systems

The Syngas Chemical Looping (SCL) process developed at The Ohio State University (OSU) uses an iron-based oxygen carrier to convert syngas into high-purity hydrogen while simultaneously capturing carbon dioxide that is readily sequestrable. A 25 kWth sub-pilot unit was successfully demonstrated multiple times on the OSU Clean Coal Research Facility, and a 250 kWth – 3 MWth pilot demonstration unit has been designed and constructed at the National Carbon Capture Center (NCCC) in Wilsonville, Alabama. The focus of this project is to develop multiple technologies to automate the startup and shutdown of chemical looping system. Success of this project will propel the advanced carbon capture method toward commercialization, hence be disruptive to the fossil fuel and power industries. Advanced process automation control architecture and imaging and optimization sensor software were developed for OSU chemical looping process. A high-level controller (HLC) consisting of decision-making and controller-selection logic integrated with sliding mode controllers (SMCs) were developed to perform chemical looping process startup and shutdown. Babcock & Wilcox Power Generation Group’s FocalPoint Optimization System was implemented to optimize the process operating conditions. The process automation controller and optimization information were realized and tested on OSU’s existing sub-pilot chemical looping test unit under atmospheric condition. The implemented control architecture was able to perform the complete process procedure from startup, steady-state reaction operation to shutdown with minimal operator intervention. The controller was also implemented on the pressurized syngas chemical looping (SCL) pilot test unit constructed at the National Carbon Capture Center (NCCC), demonstrating its pressure control capability with a designed transient state trajectory. An electrical capacitance volume tomography (ECVT) sensor device and its software were developed to image the packed moving bed and slugging fluidized bed of oxygen carriers in chemical looping systems at elevated temperatures. The ECVT device constructed was capable of tracking the subtle voidage variance along the moving bed axis as a feature for directly measuring the oxygen carrier particles’ linear velocity. Also, the high temperature ECVT device was used to study the fluidization characteristics of Geldart Group D particles.

08 HYDROGEN↗
DOE OSTI2021

Processing Aleatory and Epistemic Uncertainties in Experimental Data From Sparse Replicate Tests of Stochastic Systems for Real-Space Model Validation

This paper presents a practical methodology for propagating and processing uncertainties associated with random measurement and estimation errors (that vary from test-to-test) and systematic measurement and estimation errors (uncertain but similar from test-to-test) in inputs and outputs of replicate tests to characterize response variability of stochastically varying test units. Also treated are test condition control variability from test-to-test and sampling uncertainty due to limited numbers of replicate tests. These aleatory variabilities and epistemic uncertainties result in uncertainty on computed statistics of output response quantities. The methodology was developed in the context of processing experimental data for “real-space” (RS) model validation comparisons against model-predicted statistics and uncertainty thereof. The methodology is flexible and sufficient for many types of experimental and data uncertainty, offering the most extensive data uncertainty quantification (UQ) treatment of any model validation method the authors are aware of. It handles both interval and probabilistic uncertainty descriptions and can be performed with relatively little computational cost through use of simple and effective dimension- and order-adaptive polynomial response surfaces in a Monte Carlo (MC) uncertainty propagation approach. A key feature of the progressively upgraded response surfaces is that they enable estimation of propagation error contributed by the surrogate model. Sensitivity analysis of the relative contributions of the various uncertainty sources to the total uncertainty of statistical estimates is also presented. Finally, the methodologies are demonstrated on real experimental validation data involving all the mentioned sources and types of error and uncertainty in five replicate tests of pressure vessels heated and pressurized to failure. Simple spreadsheet procedures are used for all processing operations.

97 MATHEMATICS AND COMPUTING↗
DOE OSTI2017

Who watches the watchers?: preventing fault in a fault tolerance library

The Scalable Checkpoint/Restart library (SCR) was developed and is used by researchers at Lawrence Livermore National Laboratory to provide a fast and efficient method of saving and recovering large applications during runtime on high-performance computing (HPC) systems. Though SCR protects other programs, up until June 2017, nothing was actively protecting SCR. The goal of this project was to automate the building and testing of this library on the varying HPC architectures on which it is used. Our methods centered around the use of a continuous integration tool called Bamboo that allowed for automation agents to be installed on the HPC systems themselves. These agents provided a way for us to establish a new and unique way to automate and customize the allocation of resources and running of tests with CMake’s unit testing framework, CTest, as well as integration testing scripts though an HPC package manager called Spack. These methods provided a parallel environment in which to test the more complex features of SCR. As a result, SCR is now automatically built and tested on several HPC architectures any time changes are made by developers to the library’s source code. The results of these tests are then communicated back to the developers for immediate feedback, allowing them to fix functionality of SCR that may have broken. Hours of developers’ time are now being saved from the tedious process of manually testing and debugging, which saves money and allows the SCR project team to focus their efforts towards development. Thus, HPC system users can use SCR in conjunction with their own applications to efficiently and effectively checkpoint and restart as needed with the assurance that SCR itself is functioning properly.

97 MATHEMATICS AND COMPUTING↗
DOE OSTI2017

Validation of Methodology to Simulate Gamma Doses from Historical Weapons Tests

The United States tested nuclear weapons in the atmosphere (aboveground) from 1945 until 1963, when the nation became a signatory to the Partial Test Ban Treaty. During those tests, gamma doses were often measured within kilometers of the point of detonation. Additional gamma dose measurements were made in and around the location of any personnel conducting the test, possibly with personal dosimeters. These gamma dose measurements have been declassified to provide the personnel involved with an estimate of the total dose they received while involved with the aboveground testing program. Several years ago, interest in these gamma doses was renewed by organizations that would need to provide the public with dose estimates in the event of a radiological or nuclear weapon terrorist attack on the United States. This work provides an initial validation of the computational methods used to simulate dose from a radiological or nuclear weapon. This initial work will focus on dose from gamma rays. The sources of gamma rays from a nuclear weapon include prompt fission gammas, gammas generated via neutron interactions (capture, inelastic scattering, and activation), and gammas produced by the decay of fission products. All of these gamma ray sources for a nuclear weapon are also potential sources of gammas from a radiological weapon. However, the sources of gamma rays from a radiological weapon depend on the material present in the device, and prompt fission gammas will mostly come from spontaneous fission instead of induced fission. This paper focuses on validation using gamma ray dose measurements from nuclear detonations, which is adequate to validate the requisite transport methodologies, source term generation, and cross sections needed to model gamma doses delivered by most radiological weapons. The 1961 report on Operation Plumbbob provides an overview of how the total gamma dose delivered by a nuclear weapon is broken down by the different sources specified above. The prompt fission gamma rays contribute about 5% of the total gamma dose. The gamma rays produced by neutron interactions usually deliver the largest portion of the total gamma dose, which is typically between 55% and 85% of the total. The remainder of the total gamma ray dose is attributed to decay of fission products.

61 RADIATION PROTECTION AND DOSIMETRY↗
DOE OSTI2021

Named Data Networking for DER Cybersecurity

We present our research findings on the novel NDN protocol. In this work, we defined key attack scenarios for possible exploitation and detail software security testing procedures to evaluate the security of the NDN software. This work was done in the context of distributed energy resources (DER). The software security testing included an execution of unit tests and static code analyses to better understand the software rigor and the security that has been implemented. The results from the penetration testing are presented. Recommendations are discussed to provide additional defense for secure end-to-end NDN communications.

97 MATHEMATICS AND COMPUTING↗
DOE OSTI2024

Percheron Power Archimedes Screw Turbine Analysis (Abstract)

The development of the Percheron Power (Percheron) composite Archimedes screw turbine (AST) is based upon employing newly developed theoretical mathematical models for optimizing the water volume carried through the AST for a given diameter, combined with minimizing efficiency losses due to bypass flow and friction. The key feasibility issues associated with producing the composite blades will be to understand the strength, fatigue, and wear performance of the AST blades and associated components, and how these factors change along the length of the turbine. To get to this understanding of material property requirements, Percheron needs free-surface computational fluid dynamics (CFD) models of the AST designs and to perform interactive modeling between the turbine blade optimization and component design based on finite element method stress analysis (FEA). The workscope and analyses requested by Percheron in the Small Business Voucher (SBV) program are well aligned with PNNL capability and recent work experience in performing CFD and FEA analysis for hydropower and marine energy turbines. The CFD analysis will provide estimates of power, efficiency, and surface forces on the blades. The forces on the blade will be transferred to the FEA analysis that will be used to evaluate the material stresses. The CFD and FEA analyses will be repeated for different AST designs provided to PNNL by Percheron. The work conducted in this SBV project will complement the existing Percheron FOA project by providing better defined parameters for design and material selection for the turbine unit prior to manufacture of initial test units.

42 ENGINEERING↗
DOE OSTI2019

In Situ Characterization of Turbine Hydraulic Environment to Support Development of Fish-Friendly Hydropower Guidelines in the Lower Mekong River Region

The Mekong River is one of the most biodiverse rivers on the planet. As a result, many communities located near the river and its tributaries rely on fisheries for sustenance as well as economic viability. Along the Mekong River mainstem, there are plans for 11 new hydropower projects with potentially several hundred smaller hydropower projects along the tributaries. Currently, there is little information to guide construction of fish-friendly hydropower systems. Preliminary guidelines for construction on the mainstem Mekong call for safe upstream and downstream fish passage for 95% of target species. To understand the hydraulic conditions at existing dams in the region, Sensor Fish, a small neutrally buoyant autonomous sensor package capable of measuring and collecting in situ motion and force data, were deployed at Nam Ngum Dam in Lao PDR. The Sensor Fish were released through two turbine units—Unit 1, which contains an older 17.5-MW Francis turbine, and Unit 4, which contains a slightly newer 40-MW Francis turbine. Comparisons were made between the results from the two turbine units at Nam Ngum Dam to results for four hydroelectric dams in the U.S. Pacific Northwest for which live fish survival studies had been conducted. Three of the U.S. dams have Francis-turbine units and the other has a fish-friendly Kaplan turbine. Based on the occurrence of severe acceleration events, the survival rate of juvenile salmonids at a dam like Nam Ngum Dam would be expected to between the 11.1% to 54.1% survival rates experienced at the U.S. with Francis turbines and the 97.0% survival rate at the U.S. dam equipped with fish-friendly Kaplan turbines. Between the newer and older turbine units tested at Nam Ngum Dam, the newer Unit 4 had a higher median nadir pressure of 126 kPaA compared to 99 kPaA for Unit 1. Based on a dose-response relationship for juvenile Chinook salmon, these nadir pressures predict probabilities of mortal injury of 5% for Unit 4 and 12% for Unit 1. With respect to both pressure and acceleration, the older 17.5-MW Francis turbine had more severe hydraulic conditions than the newer 40-MW Francis turbine. Francis turbines, like the ones involved in this study, are the most common type of hydropower turbines in the throughout the world. The results from this study can be used to guide the construction of new hydropower structures and make design and operational changes to existing hydropower structures that will improve fish passage conditions.

Francis turbine, Mekong River, sustainable hydropo↗
DOE OSTI2021

Evaluating sealability of blended smart polymer and fiber additive for geothermal drilling with the effect of fracture opening size

Geothermal formations often contain extensive fracture networks. These fracture networks contribute to the significant loss of drilling fluids during geothermal drilling. Multiple loss circulation materials (LCM) such as fiber, granules, and pills have been proposed to tackle this problem but with only limited success. Recent advances in materials science have led to the development of thermoset shape memory polymers (SMP) to address the lost circulation problem. In this paper, we evaluate a thermoset SMP performance in sealing near wellbore fractures of different sizes in geothermal wells. The SMP performance was assessed using granite disks and cylindrical granite cores having fracture sizes of 1000 μm and 3000 μm. A static filtration test was performed using cedar fiber, CaCO 3 , and SMP. Results showed cedar fiber performed better than the CaCO 3 ., reducing fluid loss by 89% and improving sealing pressure by 200 psi. A novel dynamic testing unit that allows for high-temperature testing under flowing conditions was used in this study. The analysis showed that 3% by weight SMP and fiber blends could bridge and plug the 1000 μm fracture. For a larger fracture of 3000 μm width, there was a need to increase the weight concentration of the SMP to 6% to plug the fracture opening effectively. We showed the influence of key parameters such as the type of LCM, concentration, and particle size distribution in optimizing the performance of drilling fluid loss treatment.

02 PETROLEUM↗
DOE OSTI2019

Nanoparticle Injection Technology for Remediating Leaks of CO 2 Storage Formation (Final Report)

Leakage of a well can occur through the wellbore, the annulus between well tubing and steel casing, or on the outside of the casing. The overall goal of the project is to develop a new technology that can repair or reduce the leakage of wellbore. The new technology is based on simultaneously injecting nanoparticles electrochemically and removing some of the harmful ions in the system so the distressed cement materials can be densified and the corrosion risk of steel casing can be reduced. There were two objectives. One is the development of the injection technology for leakage repair and the other is the development of new numerical simulation models that can simulate and predict the performance of the new repair technology. An electro-migration testing unit and a in-house wellbore testing system were developed; healing agents with nanoparticles were selected, numerical models were developed to simulate the electro-migration technology, and the effectiveness of the new technology were evaluated.

42 ENGINEERING↗
DOE OSTI2019

Recent SAM Code Improvement to Heat Transfer Modeling Capabilities

System Analysis Module (SAM) is currently under development at Argonne National Laboratory as a modern system-level modeling and simulation tool for advanced non-light water reactor (non-LWR) safety analyses. It utilizes the object-oriented application framework MOOSE to leverage the modern software environment and advanced numerical methods. The capabilities of SAM are being extended to enable the transient modeling, analysis, and design of various advanced nuclear reactor systems. This report summarizes recent SAM code improvement to heat transfer modeling capabilities to support system and core thermal-hydraulics analysis for advanced nuclear reactor systems. These new capabilities include implementation of the energy equation for solid structure in porous medium and its coupling with porous medium flow energy equation; coupling between one-dimensional flow equation and three-dimensional heat conduction equation; coupling between two-dimensional heat structure and three-dimensional porous medium flow equations; and implementation of effective thermal conductivity correlations for solid pebble beds and its validation against High Temperature Test Unit (HTTU) experimental data. Demonstration or validation test problems are also included in this report to confirm the successful implementation of these capabilities.

1D/3D coupling↗
DOE OSTI2019

Nanoparticle Injection Technology for Remediating Leaks of CO 2 Storage Formation (Final Technical Report)

Leakage of a well can occur through the wellbore, the annulus between well tubing and steel casing, or on the outside of the casing. The overall goal of the project is to develop a new technology that can repair or reduce the leakage of wellbore. The new technology is based on simultaneously injecting nanoparticles electrochemically and removing some of the harmful ions in the system so the distressed cement materials can be densified and the corrosion risk of steel casing can be reduced. There were two objectives. One is the development of the injection technology for leakage repair and the other is the development of new numerical simulation models that can simulate and predict the performance of the new repair technology. An electro-migration testing unit and an in-house wellbore testing system were developed; healing agents with nanoparticles were selected, numerical models were developed to simulate the electro-migration technology, and the effectiveness of the new technology was evaluated.

42 ENGINEERING↗