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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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DOE OSTI2016

Fast automatic 3D liver segmentation based on a three-level AdaBoost-guided active shape model

Purpose: A robust, automatic, and rapid method for liver delineation is urgently needed for the diagnosis and treatment of liver disorders. Until now, the high variability in liver shape, local image artifacts, and the presence of tumors have complicated the development of automatic 3D liver segmentation. In this study, an automatic three-level AdaBoost-guided active shape model (ASM) is proposed for the segmentation of the liver based on enhanced computed tomography images in a robust and fast manner, with an emphasis on the detection of tumors. Methods: The AdaBoost voxel classifier and AdaBoost profile classifier were used to automatically guide three-level active shape modeling. In the first level of model initialization, fast automatic liver segmentation by an AdaBoost voxel classifier method is proposed. A shape model is then initialized by registration with the resulting rough segmentation. In the second level of active shape model fitting, a prior model based on the two-class AdaBoost profile classifier is proposed to identify the optimal surface. In the third level, a deformable simplex mesh with profile probability and curvature constraint as the external force is used to refine the shape fitting result. In total, three registration methods—3D similarity registration, probability atlas B-spline, and their proposed deformable closest point registration—are used to establish shape correspondence. Results: The proposed method was evaluated using three public challenge datasets: 3Dircadb1, SLIVER07, and Visceral Anatomy3. The results showed that our approach performs with promising efficiency, with an average of 35 s, and accuracy, with an average Dice similarity coefficient (DSC) of 0.94 ± 0.02, 0.96 ± 0.01, and 0.94 ± 0.02 for the 3Dircadb1, SLIVER07, and Anatomy3 training datasets, respectively. The DSC of the SLIVER07 testing and Anatomy3 unseen testing datasets were 0.964 and 0.933, respectively. Conclusions: The proposed automatic approach achieves robust, accurate, and fast liver segmentation for 3D CTce datasets. The AdaBoost voxel classifier can detect liver area quickly without errors and provides sufficient liver shape information for model initialization. The AdaBoost profile classifier achieves sufficient accuracy and greatly decreases segmentation time. These results show that the proposed segmentation method achieves a level of accuracy comparable to that of state-of-the-art automatic methods based on ASM.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2014

Tools for Accurate and Efficient Analysis of Complex Evolutionary Mechanisms in Microbial Genomes (Final Report)

I proposed to develop computationally efficient tools for accurate detection and reconstruction of microbes' complex evolutionary mechanisms, thus enabling rapid and accurate annotation, analysis and understanding of their genomes. To achieve this goal, I proposed to address three aspects. (1) Mathematical modeling. A major challenge facing the accurate detection of HGT is that of distinguishing between these two events on the one hand and other events that have similar "effects." I proposed to develop a novel mathematical approach for distinguishing among these events. Further, I proposed to develop a set of novel optimization criteria for the evolutionary analysis of microbial genomes in the presence of these complex evolutionary events. (2) Algorithm design. In this aspect of the project, I proposed to develop an array of efficient and accurate algorithms for analyzing microbial genomes based on the formulated optimization criteria. Further, I proposed to test the viability of the criteria and the accuracy of the algorithms in an experimental setting using both synthetic as well as biological data. (3) Software development. I proposed the final outcome to be a suite of software tools which implements the mathematical models as well as the algorithms developed.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2013

Transportation Electrification Education Partnership for Green Jobs and Sustainable Mobility

This collaborative educational project between the University of Michigan—Ann Arbor, University of Michigan—Dearborn and the Kettering University successfully executed almost all the elements we proposed to do. In the original proposal, we proposed to develop four graduate courses, six undergraduate courses, four professional short courses, a K-12 electric vehicle education kit, a Saturday morning seminar series, and a set of consumer education material to support the advancement of transportation electrification. The first four deliverables were all successfully developed and offered. When we held the kick-off meeting in NETL in Morgantown back in early 2010 with all the ten ARRA education teams, however, it quickly became clear that among the ten ARRA education grantee teams, our proposed “consume education” activities are not better or with the potential to create bigger impact than some of activities proposed in other teams. For example, the Odyssey 2010 event held by the West Virginia University team had planned and successfully reached to more than 230,000 attendees, which is way more than what our proposed 100k event could ever reach. It was under the suggestion of Joseph Quaranta, the ARRA education Program Director at that time, that we should coordinate and eliminate redundancy. The resources should then be focused on activities that have less overlap. Therefore, the originally proposed activities: Saturday morning seminar series, and a set of consumer education material were dropped from our scope. We expanded the scope of our “education kit” activity to include some educational materials, mainly in the form of videos. The target audience also changed from general public to K-12 students. The majority of the project cost (~70%) goes toward the establishment of three undergraduate laboratories, which provides critically needed hands-on learning experience for next-generation green mobility engineers. We are very proud that the ARRA money, which was distributed as part of the economy stimulus package back in 2009, was used to invest in laboratories which are already impacting the learning experience of our undergraduate and graduate students, and will continue to do so in the coming decades. The offering and enrollments of the ten undergraduate and graduate courses developed under the support of this educational grant is summarized in the table below. The grant was finalized in September 2009, and four new courses were developed and offered soon after in Winter 2010. The other six courses were developed thereafter. The total number of students who took these new courses over the duration of this grant is just over 1,000. In the first 2 years, under the DOE funding, the courses are offered more regularly. After that, the courses were considered together with other existing courses in the planning of teaching schedule and may not be offered each year. Almost all of the 10 courses have healthy enrollments and we do expect them to be offered continuously in the future. The graduate courses perhaps will be offered every 2-3 years, and the undergraduate courses most likely on a yearly basis.

33 ADVANCED PROPULSION SYSTEMS↗
DOE OSTI2016

Orange County Photovoltaic Project & Educational COmponent

The purpose of this report is to discuss the projects implemented, utilizing Department of Energy grant funds, to support the use and understanding of renewable energy in Orange County, Florida and the Greater Orlando Area. Orange County is located in the State of Florida and is most popularly referred to as Orlando. The greater Orlando area’s current population is 1,225,267 and in 2015 was the first destination to surpass 60 million visitors. Orange County utilized grant funds to add to the growing demand for access to charging stations by installing one level 2 dual NovaCharge CT4021 electric vehicle charging station at the Orange County/University of Florida Cooperative Extension Center. The charging station is considered a “smart” charger connected to a central network operated by a third party. Data collected includes the number of charging sessions, session start and end times, the electricity usage, greenhouse gases saved and other pertinent data used for reporting purposes. Orange County continues to support the use of electric vehicles in Metro Orlando and this project continues to bring awareness to our public regarding using alternative vehicles. Additionally, we offer all visitors to the Orange County/University of Florida Cooperative Extension Center free charges for their electric vehicles 24 hours a day. Since the operation of the charging station there have been 52 unique driver users, a total of 532.2258 kg of greenhouse gas savings and 159.03 gallons of gasoline savings. The installation of the additional electric vehicle charging station is part of a county-wide goal of promoting implementation of renewable energy technologies as well as supporting the use of electric vehicles including the Drive Electric Orlando & Florida programs. http://driveelectricorlando.com/ & ; http://www.driveelectricflorida.org/ . Grant funds were also used for Outreach and Educational efforts. Educational efforts about renewable energy were accomplished through the continued support as well as a proposed expansion and potential relocation of the Climate Change Education Center. The growth of the Climate Change Education Center focused on 2 educational subsectors. The first educational sector focused on an apprenticeship with university students. The second sector Orange County partnered with a hospitality college that held seminars to educate students in sustainability best practices that would influence the industry as a whole as students take jobs around the U.S. and other parts of the world. Orange County completed five of the originally proposed six educational seminars. The first seminar focused on community based social marketing techniques for driving sustainable behavior changes. The second seminar held was a green team workshop. The third seminar focused on urban sustainability planning. The fourth and fifth seminars held were Florida Energy Code workshops for building inspectors. A sixth transit oriented development seminar in partnership with Rollins College was explored, but was not conducted because the proposed on campus venue was not accessible for an extended period of time due to renovations. Additionally, an ENERGY STAR training program was conducted with students from the University of Central Florida; three of the five buildings assessed received ENERGY STAR ratings; one student completed the training and received their certification as an ENERGY STAR Specialist. Background: Location: Orange County is located in the central region of the State of Florida and is most popularly known for including the City of Orlando. The greater Orlando area’s current population is 1,225,267 and is home to large corporations such as Walt Disney World, Universal Studios Orlando, Ritz Carlton, Darden Restaurants, and the nation’s second largest convention center. Opportunities Identified: Encouraging Sustainability in Major Sectors: The Central Florida economy is largely dependent on the hospitality industry and in 2015 it was the first destination to surpass 60 million visitors. With over 60 million visitors each year, 120,000 hotel rooms, 4,000 restaurants, and 75 theme parks and attractions, the local hospitality industry provided a wealth of opportunity to reduce greenhouse gas emissions through building energy efficiency and renewable energy. Accordingly, Central Florida is an ideal training ground for teaching best practices for sustainability focused on the hospitality industry. Meeting the Growing Demand for Electric Vehicle Infrastructure: According to the 2014 U.S Clean Tech Leadership Index Report, nationwide electric vehicle ownership in the top 50 largest metro areas increased sharply in 2013; the Orlando Metro Area was ranked #5 in the nation in in terms of electric vehicle charging stations per one million people. Additionally, the Orange County 2014-2015 Annual Sustainable Orange County Report indicated there are 300 electric vehicle charging stations in Central Florida (roughly 300 charging stations within ~70 mile radius available to our residents of Orange County). By increasing and improving access to charging stations, Orange County supports the growing demand for renewable energy technologies. Project Achievements/Accomplishments: Installed an Electric Charging Station: Orange County utilized grant funds to install one level 2 dual NovaCharge CT4021 electric vehicle charging station at the Orange County/University of Florida Cooperative Extension Center. The charging station is considered a “smart” charger connected to a central network operated by a third party that monitors the number of charging sessions, session start and end times, the electricity usage, greenhouse gases saved and other pertinent data. During the six months of operation of the charging station there have been 52 unique driver users of the charging station; a total of 532.2258 kg of greenhouse gas savings and 159.03 gallons of gasoline savings. Operation and Potential Relocation of the Orange County Climate Change Education Center: The Climate Change Education Center, originally located within the Orange County Convention Center, served as a central place to inform and educate commercial and residential sectors of environmental, health, and economic benefits of renewable energy, energy efficiency, and greenhouse gas emission reductions. Grant funds were used to pay for the rent required to maintain a lease at the Convention Center, conduct five educational workshops, and for planned upgrades to the Center displays highlighting a number of energy efficiency and renewable energy projects implemented at the Orange County Convention Center and Downtown Orange County. An initial design concept for an upgraded Climate Change Education Center and educational displays was proposed. However, after the Convention Center determined the space occupied by the Climate Change Education Center; a feasibility study for relocation to the proposed area was conducted in October 2013. In December 2013, it was determined that the desired location of the for the Climate Change Education Center at the Orange County Extension Education Center provided too many construction challenges for relocation with too many building retrofits and access problems, including lack of access for loading and unloading exhibits as well as roof drainage relocations and sewer service connection issues. Another suitable location for relocating the Climate Change Education Center could not be located so the project was terminated. The Climate Change Education Center is no longer in existence in Orange County and has been eliminated. Grant funds were used to pay for marketing services for a state wide marketing program including solar & other renewable energy technologies for rebranding and developing marketing materials including web site design and updating. A website was maintained and updated the www.PowerUpGreenEnergy.com website (no longer in service). Sustainability Training for the Hospitality Industry and Major Sectors: To introduce energy efficiency and renewable energy concepts to the hospitality industry, Orange County partnered with a hospitality college that held seminars to educate students in sustainability best practices that would influence the industry as a whole as students take jobs around the U.S. and other parts of the world. Orange County completed five of the originally proposed six education seminars. Seminar topics included: driving sustainable behavior change through community based social marketing; green team programs; urban sustainability planning; and Florida Energy Code workshops for building inspectors. In partnership with Rollins College, a sixth seminar focused on transit-oriented development was explored, but was not conducted due to extended renovations at the proposed on-campus venue. Green Job Training Development: To promote green industry development and on-the-job training in occupations that encourage energy efficiency and resource reduction, Orange County piloted an ENERGY STAR training and apprenticeship program with students from the University of Central Florida; three students applied for the program; one student completed the training and received their certification as an ENERGY STAR specialist; three of the five buildings assessed received ENERGY STAR Ratings.

14 SOLAR ENERGY↗
DOE OSTI2015

Results and Analysis of the Infrastructure Request for Information (DE-SOL-0008318)

The Department of Energy (DOE) Office of Nuclear Energy (NE) released a request for information (RFI) (DE-SOL-0008318) for “University, National Laboratory, Industry and International Input on Potential Office of Nuclear Energy Infrastructure Investments” on April 13, 2015. DOE-NE solicited information on five specific types of capabilities as well as any others suggested by the community. The RFI proposal period closed on June 19, 2015. From the 26 responses, 34 individual proposals were extracted. Eighteen were associated with a DOE national laboratory, including Argonne National Laboratory (ANL), Brookhaven National Laboratory (BNL), Idaho National Laboratory (INL), Los Alamos National Laboratory (LANL), Pacific Northwest National Laboratory (PNNL) and Sandia National Laboratory (SNL). Oak Ridge National Laboratory (ORNL) was referenced in a proposal as a proposed capability location, although the proposal did not originate with ORNL. Five US universities submitted proposals (Massachusetts Institute of Technology, Pennsylvania State University, Rensselaer Polytechnic Institute, University of Houston and the University of Michigan). Three industrial/commercial institutions submitted proposals (AREVA NP, Babcock and Wilcox (B&W) and the Electric Power Research Institute (EPRI)). Eight major themes emerged from the submissions as areas needing additional capability or support for existing capabilities. Two submissions supported multiple areas. The major themes are: Advanced Manufacturing (AM), High Performance Computing (HPC), Ion Irradiation with X-Ray Diagnostics (IIX), Ion Irradiation with TEM Visualization (IIT), Radiochemistry Laboratories (RCL), Test Reactors, Neutron Sources and Critical Facilities (RX) , Sample Preparation and Post-Irradiation Examination (PIE) and Thermal-Hydraulics Test Facilities (THF).

99 GENERAL AND MISCELLANEOUS↗
DOE OSTI2015

Development of Plasmonically Cloaked Nanoparticles

An advanced in-pile multi-parameter reactor monitoring system is being proposed in this funding opportunity. The proposed effort brings cutting edge, high-fidelity optical measurement systems into the reactor environment in an unprecedented fashion, including in-core, in-cladding and in-fuel pellet itself. Unlike instrumented leads, the proposed system provides a unique solution to a multi-parameter monitoring need in core while being minimally intrusive in the reactor core. Detector designs proposed herein can monitor fuel compression and expansion in both the radial and axial dimensions as well as monitor linear power profiles and fission rates during the operation of the reactor. In addition to pressure, stress, strain, compression, neutron flux, neutron spectra, and temperature can be observed inside the fuel bundle and fuel rod using the proposed system. The proposed research aims at developing radiation-hard, harsh-environment multi-parameter systems for insertion into the reactor environment. The proposed research holds the potential to drastically increase the fidelity and precision of in-core instrumentation with little or no impact in the neutron economy in the reactor environment while providing a measurement system capable of operation for entire operating cycles. Significant work has been done over the last few years on the use of nanoparticle-based scintillators. Through the use of metamaterials, the PIs aim to develop planar neutron detectors and large-volume neutron detectors. These detectors will have high efficiencies for neutron detection and will have a high gamma discrimination capability.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2015

In-Pile Instrumentation Multi- Parameter System Utilizing Photonic Fibers and Nanovision

An advanced in-pile multi-parameter reactor monitoring system is being proposed in this funding opportunity. The proposed effort brings cutting edge, high fidelity optical measurement systems into the reactor environment in an unprecedented fashion, including in-core, in-cladding and in-fuel pellet itself. Unlike instrumented leads, the proposed system provides a unique solution to a multi-parameter monitoring need in core while being minimally intrusive in the reactor core. Detector designs proposed herein can monitor fuel compression and expansion in both the radial and axial dimensions as well as monitor linear power profiles and fission rates during the operation of the reactor. In addition to pressure, stress, strain, compression, neutron flux, neutron spectra, and temperature can be observed inside the fuel bundle and fuel rod using the proposed system. The proposed research aims at developing radiation-hard, harsh-environment multi-parameter systems for insertion into the reactor environment. The proposed research holds the potential to drastically increase the fidelity and precision of in-core instrumentation with little or no impact in the neutron economy in the reactor environment while providing a measurement system capable of operation for entire operating cycles.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2017

VERA-CS Verification & Validation Plan

This report summarizes the current status of VERA-CS Verification and Validation for PWR Core Follow operation and proposes a multi-phase plan for continuing VERA-CS V&V in FY17 and FY18. The proposed plan recognizes the hierarchical nature of a multi-physics code system such as VERA-CS and the importance of first achieving an acceptable level of V&V on each of the single physics codes before focusing on the V&V of the coupled physics solution. The report summarizes the V&V of each of the single physics codes systems currently used for core follow analysis (ie MPACT, CTF, Multigroup Cross Section Generation, and BISON / Fuel Temperature Tables) and proposes specific actions to achieve a uniformly acceptable level of V&V in FY17. The report also recognizes the ongoing development of other codes important for PWR Core Follow (e.g. TIAMAT, MAMBA3D) and proposes Phase II (FY18) VERA-CS V&V activities in which those codes will also reach an acceptable level of V&V. The report then summarizes the current status of VERA-CS multi-physics V&V for PWR Core Follow and the ongoing PWR Core Follow V&V activities for FY17. An automated procedure and output data format is proposed for standardizing the output for core follow calculations and automatically generating tables and figures for the VERA-CS Latex file. A set of acceptance metrics is also proposed for the evaluation and assessment of core follow results that would be used within the script to automatically flag any results which require further analysis or more detailed explanation prior to being added to the VERA-CS validation base. After the Automation Scripts have been completed and tested using BEAVRS, the VERA-CS plan proposes the Watts Bar cycle depletion cases should be performed with the new cross section library and be included in the first draft of the new VERA-CS manual for release at the end of PoR15. Also, within the constraints imposed by the proprietary nature of plant data, as many as possible of the FY17 AMA Plant Core Follow cases should also be included in the VERA-CS manual at the end of PoR15. After completion of the ongoing development of TIAMAT for fully coupled, full core calculations with VERA-CS / BISON 1.5D, and after the completion of the refactoring of MAMBA3D for CIPS analysis in FY17, selected cases from the VERA-CS validation based should be performed, beginning with the legacy cases of Watts Bar and BEAVRS in PoR16. Finally, as potential Phase III future work some additional considerations are identified for extending the VERA-CS V&V to other reactor types such as the BWR.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗
DOE OSTI2019

Integrated Solutions for Optimized Performance (ISOP) Final Technical Report

The goal of this project was to demonstrate technical feasibility of an integrated approach for deep energy retrofits by packaging innovative technologies with smart communicating controls that represent the next generation of energy efficiency. The integrated solutions for optimized performance (ISOP) package integrates (i) advanced lighting and plug load controls; (ii) intelligent daylight harvesting through automated self-powered shades and window films; (iii) advanced HVAC controls sequences (ASHRAE Guideline (GDL) 36); and (iv) fault detection and diagnosis (FDD) and continuous commissioning (CCx) using advanced analytics. These technologies address energy use across multiple building end uses that represent more than 60% of the energy consumption in all commercial buildings. The project was structured to be implemented over three budget periods: Budget Period 1 scope included site selection, project design, site-specific customization of technology packages, procurement of technologies, initiation of installation of technologies, the development of a measurement and verification plan and collection of pre-retrofit data collection. The first year go/no-go decision was based on securing host sites representing 250,000 sq. ft. of occupied operational spaces, savings analysis, technology procurement and initiation of installation. Budget Period 2 planned to complete technology installations and initiate data collection of post-retrofit performance data. The second year go/no-go was to be the completion of technology installations and commissioning, metering and data collecting to support the requirements laid out in site specific M&V plans. Budget Period 3 planned to collect and analyze post-retrofit performance data and provide data and reporting to support energy efficiency rebate programs. After the team completed activities planned for Budget Period 1, the team reached a Go/No-Go Decision Point. At that point, TRC recommended that DOE discontinue the project without prejudice due to challenges with securing demonstration sites to meet the full 250,000 sf of occupied operational spaces and DOE concurred. In Budget Period 1, the TRC team developed criteria to recruit and evaluate potential demonstration host sites. TRC worked with Princeton University, the project demonstration partner, to identify buildings on their campus as potential candidates for the demonstration. Following the selection of demonstration sites, the TRC team customized energy technology packages according to the needs and characteristics of each site. TRC defined technology specifications, identified vendors, and conducted analysis to estimate energy and cost savings potential. The project team then developed schedules for technology procurement processes and scheduled for installation at all selected demonstration sites. The project team worked with Princeton University and DOE to develop an approach to verify energy savings achieved through measurement and verification (M&V) 2.0 methods. Princeton University initiated open bids to procure the necessary materials and installation contractors. Bid results came back higher than estimates due to a couple of factors – lack of familiarity of the bidders with the proposed technologies and lack of local trained installers to execute the installation of these new measures. Due to the higher bids, projects no longer met the internal cost-effectiveness criteria used by Princeton to proceed with procurement of the full suite of technologies as proposed in ISOP. Princeton had already procured parts of the ISOP package as part of a campus-wide initiative for FDD and lighting retrofits, but with the higher costs for other ISOP components, Princeton could no longer commit to the full ISOP package on the selected sites. Based on this, the team reached the Go/No-Go decision point, where they decided not to proceed with the project. Princeton is separately installing portions of the ISOP package where they individually meet Princeton’s payback criteria but on a different schedule than would have been needed for the DOE ISOP project. The team has learned several lessons from project progress in the first budget period. The team will utilize these lessons in future projects, as should any team which proceeds with a project around the ISOP technology. The first lesson is that more information about the proposed sites is required earlier in the process (perhaps even at the proposal stage) in order to have a successful demonstration. Technical details not evident earlier in the process (such as the TLED limitations for ALCS) can derail project execution. The second lesson is that pricing of emerging technologies is highly variable due to lack of familiarity of local installers and distributor with the proposed technologies as well as alternate bids using products they were more familiar with, but that cost more than the ones proposed by TRC. Finally, the last major lesson is that the host site’s internal project criteria is of critical importance. Based on these higher installed costs and lack of an informed installer base for the products proposed for this project, the project does not meet Princeton’s simple payback goals of five years.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2020

Transition Core Planning and Safety Analyses in Support of LEU Fuel Conversion of the University of Missouri Research Reactor (MURR)

The University of Missouri Research Reactor (MURR®) is one of six U.S. High Performance Research Reactors (USHPRR), including one critical facility, that is working with the National Nuclear Security Administration (NNSA) Office of Material Management and Minimization (M3) Reactor Conversion Program to convert from highly enriched uranium (HEU) to low-enriched uranium (LEU) fuel. The M3 Reactor Conversion USHPRR Project objectives include the development of LEU fuel element designs that will ensure safe reactor operations and to maintain the existing experimental performance of each facility. The work is being conducted through many inter-related activities being completed by four Project Pillars: Fuel Qualification (FQ), Fuel Fabrication (FF), Reactor Conversion (RC), and Cross Cutting (CC). A new type of LEU fuel based on an alloy of uranium-10 wt% molybdenum (U-10Mo) is expected to allow the conversion of those USHPRR, like MURR, requiring higher density fuels. The very-high-density LEU U-10Mo monolithic fuel is currently undergoing irradiation testing and post-irradiation examination under a planned and documented fuel qualification effort. The FQ Pillar will document fuel property and fuel performance data and qualify the fuel for use in these reactors. The FF Pillar is fabricating fuel for ongoing and future irradiation tests, as well as conducting fabrication demonstrations to validate or update preliminary fabrication assumptions. The FF Pillar is also working to develop and install commercial manufacturing capacity with the U-10Mo monolithic fuel to produce prototypic fuel. Working with the RC Pillar at Argonne, MURR has progressed through a preliminary fuel element design using preliminary data for the proposed monolithic alloy of U-10Mo. Analyses were completed in previous work that found for typical equilibrium operations with the preliminary LEU fuel element design, in conjunction with a power uprate to 12 MW and appropriate changes to the MURR Limiting safety system settings (LSSS), MURR will have adequate margins to safety for steady-state operations and postulated transient accidents and will have experimental performance in key locations that meets or exceeds current operations with HEU fuel. The purpose of this work is to develop a sequence of transition cycles that will enable MURR to transition from operation with the reactor core loaded with fresh LEU fuel elements only to typical equilibrium operations with mixed-burnup cores following conversion while meeting operational requirements on safety and experimental performance. It is expected that the use of fresh LEU fuel at conversion and subsequent low burnup of the LEU fuel elements that will initially be available for use following conversion will result in critical control blade positions that will substantially change the axial power distribution in the core and the neutron flux available in key experimental locations relative to equilibrium LEU operations. Given the constraints of MURR safety margins, operational practices, and production and research, a novel method has been developed to identify a transition sequence that minimizes the time MURR operates atypically compared to the current prototypic cycles using HEU fuel. The proposed transition sequence moves quickly to the same sort of equilibrium cycles for the LEU fuel that have already been evaluated in documented preliminary safety analyses. Although shifting the neutron flux peak to the lower half of the core during initial cycles with LEU at 12 MW reduces the experiment performance in some key locations relative to current HEU operations at 10 MW, all LEU cores provide an average performance that meets or exceeds that of HEU. An LEU cycle is reached that meets or exceeds the level of experimental performance predicted for current HEU and equilibrium LEU operations in more than 450 key locations identified by a reactor specialist at MURR by the 23rd cycle following conversion and that afterwards will enable MURR to consistently meet its experimental performance requirements. The proposed transition sequence only requires the fabrication of 34 fresh LEU elements in the first year of operation and does not exceed the anticipated availability of fresh elements that can be produced by the fuel fabricator. By the third year after conversion, 22 fresh LEU elements will be required each year, which is the same as expected for equilibrium LEU operations and the same as current operations with HEU fuel. The proposed transition sequence thus combines a relatively short time period before equilibrium burnup is achieved, a temporary increase of fuel elements needed annually relative to typical operations that are within the production capabilities of the fuel fabricator, and demonstrates comparable experimental performance of the LEU cores relative to current HEU operations. Further measures may be taken to reduce any initial experimental performance penalty even further, where possible, by repositioning certain experiments to leverage the increased performance in the lower axial experimental positions in the initial cycles following conversion or leaving the experiments in the irradiation facilities longer in order to achieve the required neutron fluence. This analysis may require refinement depending on the experimental facilities in use at the time of conversion. Nonetheless, the results presented here, including the experimental performance, core burnup, and critical control blade positions throughout the transition cycles, show that the proposed transition cycle fuel management patterns are consistent with what is expected and desired for MURR operation with LEU U-10Mo fuel. Detailed core power distributions from the neutronics models were also used to evaluate safety margins during steady-state operations for the selected transition cycles and the equilibrium LEU core. It is shown that there are adequate safety margins for both steady-state operations and postulated accident scenarios. For the steady-state operations with the preliminary LEU fuel element design the analysis predicts at least 2.49 MW margin to the onset of flow instability at the LSSS power of 15 MW. Considering the LSSS power is 125% of full license power, the margin to OFI is sufficient. In addition, the critical heat flux ratio at LSSS power is well above the requirement of CHFR > 2.0 from NUREG-1537 for all considered cases. For postulated transient accidents, the minimum margin to the fuel temperature safety limit is at least 109 °C. In summary, the proposed sequence of core loadings for MURR operations following conversion to LEU fuel and a power uprate to 12 MW provides sufficient safety margins for both steady-state operations and postulated transient accidents during a proposed sequence of transition cycles to equilibrium operations. Analysis has shown that there are some local experimental performance penalties during the initial cycles. Although there are local shifts in the experimental performance, on average all LEU cores at 12 MW have equal or higher performance than HEU at 10 MW. Temporary adjustments are being planned that will produce suitable experimental performance during these cycles. The results indicate that for the equilibrium LEU core the experimental performance exceeds that of current HEU operations in all key locations while also demonstrating sufficient safety margins.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2024

Porous Organic Cage Membranes for Molecular Gas Separations (Final Technical Report for DE-SC0021357)

This proposal aims at demonstrating the development of a novel family of membranes, composed of porous organic cages (POC) which offer the possibility of displaying high separation performance for challenging molecular gas separations relevant to natural gas purification, and olefin/paraffin separation. The proposed POCs synthesized in membrane form will display the most desirable properties of polymers (facile processability and flexibility) and inorganic materials (hierarchically ordered pores with molecular sieving properties) leading to highly selective and permeable membranes. POCs should display distinctive structural, compositional, adsorption and transport properties than those of conventional porous materials, opening the doors for a new research direction in membrane science, and gas separations. Our preliminary results demonstrate the feasibility of preparing POC crystals with controlled size, and continuous POC membranes with remarkable high permeances, and separation ability for CO 2 /CH 4 , N 2 /CH 4 and C 3 H 6 /C 3 H 8 separations serving as a solid foundation for our proposed work. Fundamentally, this proposal aims at elucidating separation mechanisms of different gas mixtures related to natural gas composition, and olefin/paraffin separation over porous organic cage membranes. The proposed research will result in fundamental understanding of adsorption and transport properties of industrially relevant gas molecules through novel microporous membranes, and may lead to the development of a cost effective membrane technology for natural gas purification, and olefin/paraffin separation surpassing the conventional benchmark technology distillation. Furthermore, we aim at demonstrating selective water transport through POC membranes, which can be positively impactful in numerous industrial applications in which water is present. The ability to fabricate thin, chemically and mechanically stable POC membranes for societal relevant gas separations constitute a new and distinctive direction in membrane science. Our proposed work aims at addressing some of the challenges recognized in the Research Agenda for Transforming Separation Science . Specifically: (a) advancing understanding of complex mixtures on separation performance; (b) exploring thermodynamic and kinetic mechanisms through the elucidation of separation mechanisms, and (c) study potential stability issues of the membranes to be assessed by evaluating the long term membrane stability and performance at various temperatures and pressures. The team is uniquely qualified to execute the proposed work. The PI has solid expertise in the rational molecular engineering design of porous crystalline membranes for molecular gas separations. The PNNL collaborator has extensive experience in the synthesis, characterization, and functional applications of microporous crystals, with particular emphasis on gas adsorption.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2025

An Architectural Survey of the U12G Tunnel Historic District, Nevada National Security Site, Nye County, Nevada

The U.S. Department of Energy (DOE), in conjunction with the National Nuclear Security Administration Nevada Field Office (NNSA/NFO), proposes to demolish six buildings and three storage areas located at the U12g Tunnel portal area in Area 12 of the Nevada National Security Site (NNSS). The buildings are 12-358 (Signal Vault); 12-201800 (Storage Quonset Hut); 12-202555 (Walker Shack); 12-868 (Pipe Assembly); 12-B100933 (Electrical Shop); 12-B100944 (Conference Room); and Storage Area 1; Storage Area 2; and Storage Area 3. The buildings and storage areas were selected for demolition as part of the DOE’s Real Property Efficiency Plan to reduce the footprint of unused and non-operational facilities on the NNSS. They are all vacant and have no proposed uses for current or upcoming NNSS missions. Demolition activities constitute an undertaking subject to review under Section 106 of the National Historic Preservation Act (NHPA) (54 United States Code [USC] § 306101) and its implementing regulations, 36 Code of Federal Regulations (CFR) Part 800. Identification efforts began with resources proposed for demolition in federal Fiscal Year (FY) 23. Four buildings were proposed to be demolished in FY23 (12-358, 12-868, 12-201800, and 12-202555). These buildings and the U12g Tunnel Historic District (SHPO No. D444) were recorded in Identification, Evaluation, and Finding of Adverse Effect for the Proposed Demolition of Five Buildings in Area 12, Nevada National Security Site, Nye County, Nevada (Menocal et al. 2023). Identification efforts indicated three buildings (12-358, 12-201800, and 12-868) supported nuclear testing in the U12g Tunnel. The fourth building post-dated the use of U12g Tunnel for nuclear testing activities. The report recommended that three of the four buildings (12-358, 12-201800, 12-868) and the U12g Tunnel Historic District may be eligible for the National Register of Historic Places (NRHP). The report also found that the undertaking would have an adverse effect on the three buildings and on the historic district. The Nevada State Historic Preservation Office (SHPO) concurred with the report’s findings (Reed 2023). The U12g Tunnel was determined eligible as a historic district under the Secretary of the Interior’s (SOI) Significance Criterion A, at the local level, in the context of the Cold War as an underground testing environment for the development of nuclear weapons and to assess the effects of a nuclear explosion on materials and equipment with a period of significance from 1959 to 1971. It was also determined eligible under Significance Criterion C for embodying the distinctive characters of a horizontal tunnel complex used for nuclear testing and as a significant and distinguishable entity. The three buildings were determined to be contributing elements of the district. The undertaking was expanded with the addition of two buildings and three storage areas proposed to be demolished and located within U12g Tunnel Historic District in FY24. These five resources (12-B100933, 12-B100944, and Storage Areas 1, 2, and 3) were recorded in Supplemental Identification, Evaluation, and Finding of Effect for Additional Proposed Demolition at U12g Tunnel, Area 12, Nevada national Security Site, Nye County, Nevada (Brannan et al. 2024). Identification efforts indicated that the two buildings and Storage Area 1 supported nuclear testing in the U12g Tunnel. Storage Area 1 and Storage Area 2 post-dated the nuclear testing activities at U12g Tunnel and were not recommended as contributing elements to the district. The report also found that the undertaking would have an adverse effect on the newly identified buildings and one storage area and on the historic district. The SHPO concurred that the expanded undertaking would result in adverse effects to historic properties (Reed 2025). To resolve these adverse effects, NNSA/NFO, in consultation with the SHPO, is following standard mitigation as stipulated in the 2024 Programmatic Agreement DE-GM58-22NA25554 Among the U.S. Department of Energy and the Nevada State Historic Preservation Officer and the Advisory Council on Historic Preservation Concerning the Protection of Historic Properties on the Nevada National Security Site, Nye County, Nevada (hereafter referred to as the NNSS PA). The standard mitigation measures are outlined in Appendix D of the NNSS PA. As such, this architectural survey has been prepared in accordance with Appendix D of the NNSS PA and follows the report format outlined in Appendix F. It includes a historic context that describes the district’s origin, history, and support functions, its significance in the context of nuclear testing on the NNSS, and identifies contributing and non-contributing elements within the district. The report is accompanied by Architectural Resource Assessment (ARA) forms for individual resources and a Historic District Resource Assessment (HDRA) for the U12g Tunnel Historic District. In total, this architectural report identified 32 primary resources within the district boundary. Six of the primary resources were previously identified as contributing elements. An additional 17 resources are recommended as contributing elements to the district for a total of 23 contributing elements. The other nine resources identified are recommended as non-contributing elements to the district.

12-201800↗
DOE OSTI2025

Development of Transformative Preparation Methods to Push up High Q&G Performance of FRIB Spare HWR Cryomodule Cavities

The FRIB accelerator project construction, a top priority of US nuclear science, was completed in January 2022, and is now moving to user operation. The stable and reliable operation of the accelerating cryomodules is essential in achieving/fulfilling DOE and user expectations. So far, FRIB cryomodules meet all FRIB specifications for cavity performance. However, during the lifetime of machine operation, degradation of cryomodule performance is possible, as reported in similar operating facilities (CEBAF, SNS). If cryomodule degradation is observed at FRIB, the under-performing cryomodule will require replacement/maintenance. In effort to manage operational reliability, FRIB plans to construct a 0.53 half-wave cryomodule to serve as an active spare. In a parallel effort, FRIB will also work toward increasing operational Q and gradient of spare cryomodule cavities to gain an overall performance margin to support future operational reliability. The current FRIB cavity designs have a potential to operate at gradients higher than 8 MV/m, but are currently limited by field emission (FE) and/or high field Q slope (HFQS); known issue in buffered chemical polished (BCP) treated cavities. The proposal looks to develop transformative surface preparation treatments to improve the operational gradient of spare cryomodules higher than 10 MV/m while maintaining high Q. Thus, increasing operational margin by 30 - 50%. With the goal to improve operational reliability set, the proposal will investigate multiple objectives as possible paths forward to achieve an overall increase in cavity performance and gain a better understanding of SRF limiting mechanisms. The proposal will study the application of different chemical surface treatments to 0.53 half-wave cavities, with the addition of low temperature bakes (LTB), and measure their effects on accelerating performance. Proposed chemical treatments to be explored in this proposal include conventional EP acid mixtures, as well as innovated EP and BCP acid mixtures designed to simplify processing paths in migrating FE and HFQS. The proposed transformative treatment wet N-doping also has the potential to replicate recent advancements in SRF technology relating to nitrogen doping and high Q operation without the requirement for an ultra-high vacuum annealing furnace; currently being developed at FNAL and JLAB. In parallel, high Q performance relating to flux trapping will be investigated with the installation of a second layer of magnetic shielding in the vertical test Dewar. The research objectives presented in the proposal, and their corresponding effects on cavity performance, will provide essential knowledge and future guidance to the SRF community and provide possible paths for future SRF based projects and applications.

43 PARTICLE ACCELERATORS↗
DOE OSTI2026

Cooperative Agreement To Analyze variabiLity, change and predictabilitY in the earth SysTem (CATALYST)

CATALYST proposes to perform foundational coordinated research in a team-oriented collaborative effort aimed at advancing a robust understanding of modes of Earth system variability and change using models, observations and process studies. The proposed research will address the DOE/BER mission by exploring the limits to predictability, identifying fundamental underlying mechanisms, quantifying interactions among modes of variability, and discovering tipping points in the Earth system to understand the current and future impacts of these phenomena on regional and global climate. Four fundamental gaps are identified in our knowledge of the Earth system: 1) What are the limits to predictability on various timescales? 2) What are the interactions among modes of Earth system variability? 3) How may modes of Earth system variability change in response to changes in external forcing, and what are the tipping points involved with those changes? 4) How are high impact events connected to modes of Earth system variability and how may they change in the future? Related to those gaps in our knowledge, we formulate four research objectives to address those gaps using a combination of Earth system models (ESMs) and machine learning (ML) methods. Research Objective 1 (RO1) addresses the first gap above and proposes to understand modes of variability and their limits of predictability on subseasonal to decadal timescales using ESMs and ML. Research Objective 2 (RO2) addresses the second gap and proposes to use a hierarchy of models to understand relevant processes and feedbacks related to how modes of variability interact with each other. Research Objective 3 (RO3) is designed to study the third gap and proposes to examine the role of external forcings in changes of modes of Earth system variability and their interactions, and the likelihood and predictability of tipping points and irreversible changes. Research Objective 4 (RO4) will address the fourth gap and proposes to use high resolution ESMs, regionally refined models (RRMs), and ML methods to investigate the relationships between high impact events (e.g. flash droughts and precipitation extremes, atmospheric rivers (ARs), tropical cyclones (TCs), storm surge/sea level rise), the synoptic systems that produce them, and their changes related to modes of Earth system variability. The research will involve the use of the Community Earth System Model (CESM), Energy Exascale Earth System Model (E3SM), CMIP multi-model data sets, a hierarchy of simpler models, and numerous observational data sets. In the course of the proposed research, CATALYST will contribute to metrics and diagnostics that will be integrated in Coordinated Model Evaluation Capabilities (CMEC), particularly with regards to the Quasi-biennial Oscillation (QBO) and its interactions with the Madden-Julian Oscillation (MJO), high atmospheric pressure blocking, and new precipitation metrics.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2012

Salt Disposal Investigations to Study Thermally Hot Radioactive Waste In A Deep Geologic Repository in Bedded Rock Salt - 12488

A research program is proposed to investigate the behavior of salt when subjected to thermal loads like those that would be present in a high-level waste repository. This research would build upon results of decades of previous salt repository program efforts in the US and Germany and the successful licensing and operation of a repository in salt for disposal of defense transuranic waste. The proposal includes a combination of laboratory-scale investigations, numerical simulations conducted to develop validated models that could be used for future repository design and safety case development, and a thermal field test in an underground salt formation with a configuration that replicates a small portion of a conceptual repository design. Laboratory tests are proposed to measure salt and brine properties across and beyond the range of possible repository conditions. Coupled numerical models will seek to describe phenomenology (thermal, mechanical, and hydrological) observed in the laboratory tests. Finally, the field test will investigate many phenomena that have been variously cited as potential issues for disposal of thermally hot waste in salt, including buoyancy effects and migration of pre-existing trapped brine up the thermal gradient (including vapor phase migration). These studies are proposed to be coordinated and managed by the Carlsbad Field Office of DOE, which is also responsible for the operation of the Waste Isolation Pilot Plant (WIPP) within the Office of Environmental Management. The field test portion of the proposed research would be conducted in experimental areas of the WIPP underground, far from disposal operations. It is believed that such tests may be accomplished using the existing infrastructure of the WIPP repository at a lower cost than if such research were conducted at a commercial salt mine at another location. The phased field test is proposed to be performed over almost a decade, including instrumentation development, several years of measurements during heating and then subsequent cooling periods, and the eventual forensic mining back of the test bed to determine the multi-year behavior of the simulated waste/rock environment. Funding possibilities are described, and prospects for near term start-up are discussed. Mining of the access drifts required to create the test area in the WIPP underground began in November 2011. Because this mining uses existing WIPP infrastructure and labor, it is estimated to take about two years to complete the access drifts. WIPP disposal operations and facility maintenance activities will take priority over the SDI field test area mining. Funding of the SDI proposal was still being considered by DOE's Offices of Environmental Management and Nuclear Energy at the time this paper was written, so no specific estimates of the progress in 2012 have been included. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2018

Development of a Technical Standard for Radiological Characterization of DAW - 18062

Throughout its 70+-year history, the U.S. Department of Energy (DOE) and its predecessor agencies have performed a wide mission involving nuclear materials and weapons development, production, testing, and modernization. While the initial mission components relied heavily upon reactor physics and chemistry, the environmental programs have increasingly relied upon development of more accurate and effective measurement methodologies to determine the radiological and chemical properties of the unique waste streams that were generated during the weapons production and testing mission. Over time, the DOE laboratories and former production sites have developed a wide range of site-specific processes and procedures for conducting radiological characterization of dry active waste (DAW) that is managed as low-level radioactive waste. This has resulted in a Complex-wide variability among sites with respect to the methodologies and instrumentation used to characterize individual waste streams. The DAW-type waste was selected for development of a characterization standard since it is a simple, voluminous, and repetitive waste stream with a substantial knowledge base, established experience history at multiple site locations, and the potential for realization of programmatic benefits though standardization. The Energy Facility Contractors Group (EFCOG) Waste Management Working Group (WMWG) has proposed the development of a new DOE Technical Standard for radiological characterization of DAW. The purpose of the proposed new standard is to provide a technical resource that integrates and enhances the utilization of current site-specific methodologies and processes. A Technical Basis Document (TBD) has been prepared to support the development and utilization of the new standard by providing detailed information for use by site personnel when implementing the guidance provided in the standard. It also provides the rationale for and details concerning the recommended technical approaches for radiological characterization of representative DAW-type waste streams. The TBD will be included as an appendix to the proposed standard. Adoption of a standardized approach to DAW characterization will take advantage of multiple applications for a technology that is both mature and stable. The DAW characterization process is repetitive and lends itself to implementation at a wide range of operating locations - resulting in economies of scale, compliance with regulatory requirements, and consistent implementation of procedures which support design, operations, maintenance, and management of facilities, activities and programs. The purpose of the proposed new Technical Standard for DAW Radiological Characterization is to integrate and improve the utilization of current site-specific methodologies and processes and will include a comprehensive evaluation and comparison of current radiological characterization methodologies to determine which ones are most reliable and effective in producing relevant and valid data. In view of the long history and participation by several agencies in the regulation of nuclear programs, existing Voluntary Consensus Standards have also been reviewed for relevancy and applicability to the new proposed standard. The proposed new Standard will be developed in concert with existing scientific and regulatory guidance to produce a document that incorporates the state of current knowledge and site practices with a graded approach to applying those methodologies that are applicable and effective for characterizing a wide range of DAW-type wastes - including, but not limited to, debris, low specific activity (LSA) material, and surface contaminated objects (SCO). Under the leadership of the National Laboratory Subgroup of the EFCOG/WMWG), an EFCOG team will develop the proposed technical standard. This process will incorporate the information gathered during preparation of the TBD, which will serve as a technical resource to support the technical approach for selection of DAW characterization methodologies. Preparation of the TBD included a detailed survey of historical site practices and examination of the characterization approaches and measurement methodologies currently being applied to DAW-type wastes. Future activities include the development and submittal of a Project Justification Statement that will be submitted to the DOE Technical Standards Program for review and comment. The EFCOG/WMWG Team will respond to reviewer comments, as required. Following final concurrence by affected organizations through the DOE Technical Standards Coordination process, the EFCOG/WMWG Team will prepare the draft technical standard and respond to comments generated during RevCom review and final format review by the DOE Technical Standards Management Program. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2013

Using Compliance Analysis for PPP to bridge the gap between SEA and EIA: Lessons from the Turcot Interchange reconstruction in Montréal, Québec

There is increasing concern about the disjunct between the intent of higher level government goals and actual projects “on the ground” in Canada. Although strategic environmental assessment (SEA) and a wide variety of plans, policies and programmes (PPP) contain and promote goals that envision a movement towards social, economic and environmental sustainability, these goals are not necessarily upheld by large-scale projects and their environmental impact assessments (EIAs). This disconnect is often illustrated through anecdotal observations. However, to be able to overcome this disjunct it is imperative to come to a clearer understanding of the degree of sustainability or unsustainability of large-scale developments and the way in which they “measure up” in terms of the goals when compared to alternative options. This article proposes a Compliance Analysis method for investigating the level of harmonization between SEA, PPP and proposed projects and their possible alternatives (CAPPP). This method is quantified through a Likert scale which allows for comparison of alternatives for decision making and analytical purposes. The 2009 proposal for the Turcot Exchange redevelopment in Montréal, Québec, put forward by the Ministry of Transport of Québec (MTQ), as well as two alternative proposals, were utilized as a case study to clearly demonstrate the CAPPP methodology and its applicability. The approved plan for the Turcot redevelopment proposed by MTQ was found to be in poor compliance with the majority of the 178 goals in the six sectors that were examined (air quality, climate change, health, noise, socioeconomic, transport), while alternative proposals were found to be in greater accordance with the intentions of governmental SEA and PPP. Synthesis and applications: The CAPPP methodology is a versatile “watchdog” tool for the examination of the level of compliance between stated goals for regions, industrial sectors, or governments and the EIAs of concrete projects “on the ground”. CAPPP can be used as a tool for comparative analysis in decision-making situations at various scales. CAPPP is a fairly straight-forward method that can be used by policy makers, EIA experts, and members of the general public alike. Highlights: ► We investigated the level of harmonization between SEA, plans, policies and programmes and EIA projects. ► We created a new methodology: the goal compliance analysis (GCA). ► We tested it on an ongoing project, the Turcot Interchange in Montreal, Canada. ► The method is straight-forward and can be used by policy makers, EIA experts, and members of the general public alike.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2024

Constitutive model development of aluminum alloy 1100 for elevated temperature forming process

Commercially pure aluminum alloy, AA1100, presents good electrical and thermal conductivity, high formability, and low cost. Those favorable characteristics have the potential to enable bipolar plates with improved economics and enhanced performance compared to current stainless steel bipolar plates for proton exchange membrane fuel cells. An accurate constitutive model is essential to develop and optimize processing parameters and effectively control the forming process. Here, the objective of this work is to develop a constitutive model of AA1100 that is able to simulate stress-strain relation, formed geometry, and predict the onset of fracture strain to avoid forming failure. Initially, a set of tensile tests at temperature between 300 and 500°C and strain rate between 0.005 and 1.0/s were conducted to examine the deformation behavior. Then, a set of damage-based unified visco-plastic constitutive equations is proposed and calibrated based on the results of stress-strain data. A genetic algorithm optimization method is applied to search for best fitting material constants in constitutive equations. The proposed model shows good predictability of both the stress-strain relation and fracture strain at low strain rate and high temperature conditions. The accuracy of proposed model is also evaluated statistically. A comparison of the proposed model with three popular models (Arrhenius-type mode, Johnson-Cook model and Zerilli-Armstrong model) was made. The proposed model shows the best experimental agreement with correlation coefficient of 0.96 in contrast to 0.25, 0.38 and 0.75 for the popular models, respectively. The proposed model can help to optimize the elevated temperature forming process and guide die design to enable optimal geometric features in the formed components.

08 HYDROGEN↗