Spring 2022 Colloquium

April 29, 2022March 9, 2023

What can nuclear engineering learn from design research? Integrating theory and evidence from contemporary nuclear reactor design into policy design

SPEAKER:

Aditi Verma

ASSISTANT RESEARCH SCIENTIST, ASSISTANT PROFESSOR (FALL 2022)

DATE/TIME:

FRI, 04/29/2022 - 3:00PM TO 4:00PM

LOCATION:

3105 Etcheverry Hall

Abstract

While nuclear reactor design is recognized as an essential skill and intellectual output of academic nuclear engineering, little attention has been paid within the discipline to the structure of the reactor design process and how factors beyond physical constraints influence design outcomes. In this talk, I describe the first systematic exploration of the nuclear reactor design process through the application of methodological and theoretical tools developed within the mechanical engineering design research field. Empirically based on a study of 27 American and 5 French contemporary reactor projects, this work examines how reactor designers make decisions in the early foundational stages of design such as conceptualizing the available design space and making design choices around cost, safety, and performance. The findings of this study reveal that the structure of the design process and its outcomes are significantly shaped by the identity and expertise of the designer as well as the site of the design work.

They also highlight the importance of social determinants of design outcomes particularly in the early, critical stages of design, and point to the need for a richer understanding of the reactor design process that goes beyond the long-held view focused on engineering analysis as propounded in nuclear engineering pedagogy. A deeper comprehension of these determinants of design outcomes is likely to yield valuable insights for design practice, pedagogical purposes, and chiefly for the creation and implementation of policies in the nuclear energy sector. In closing the talk, I will briefly describe some of these future research directions.

Biography

Dr. Aditi Verma joined NERS in the Fall of 2021 as an Assistant Research Scientist and will become an Assistant Dr. Verma joined NERS in the Fall of 2021 as an Assistant Research Scientist and will become an Assistant Professor in the Fall of 2022. She will also support and interact with the Fastest Path team as a Faculty Associate. Verma is a Visiting Scholar at the Harvard Kennedy School Belfer Center for Science and International Affairs’s Project on Managing the Atom, and former Stanton Nuclear Security Postdoctoral Fellow at the Belfer Center where she was jointly appointed by the Project on Managing the Atom and the International Security Program. At MIT, she was a Burchard Scholar and a Kelly-Douglas Fellow.

April 22, 2022March 9, 2023

Imaging at the Speed of Light – Reconstruction-Free Radionuclide Imaging

SACRAMENTO, Calif., July 27, 2015

At UC Davis campus Dr. Simon Cherry on July 27, 2015.

Photo by Robert Durell

SPEAKER:

Simon R. Cherry Professor, Department of Biomedical Engineering and Department of Radiology

DATE/TIME:

FRI, 04/22/2022 - 3:00PM TO 4:00PM

LOCATION:

3105 Etcheverry Hall

Positron emission tomography (PET) is a widely used medical imaging technique, and like many other tomographic imaging modalities, relies on an image reconstruction step to produce cross-sectional images. Detection and localization of the back-to-back annihilation photons produced by positron-electron annihilation defines the trajectories of these photons, which when combined with tomographic reconstruction algorithms, permits recovery of the spatial distribution of positron-emitting radionuclides. Time-of-flight information, typically at the level of 200-400 ps in modern PET systems is used to constrain the reconstruction process. Once the time-of-flight resolution is improved by an order of magnitude to ~30 ps, a new regime is encountered where radioactive decay events can be directly localized without the need for tomographic reconstruction. In this presentation we show how prompt Cherenkov luminescence, photodetectors with very fast single photon response times, and deep-learning based timing pickoff algorithms are combined in an ultra-fast radiation detector to achieve a timing resolution of 32 ps, localizing positron-electron annihilation sites to 4.8 mm. We also show this is sufficient to directly generate a cross-sectional image of positron-emitting radiotracers.

Simon R. Cherry, Ph.D. received his B.Sc.(Hons) in Physics with Astronomy from University College London and a Ph.D. in Medical Physics from the Institute of Cancer Research, University of London. He is currently Professor in the Departments of Biomedical Engineering and Radiology at the University of California, Davis. Dr. Cherry’s research interests focus on the development and application of biomedical imaging systems. Dr. Cherry is a fellow of six professional societies and served as Editor-in-Chief of the journal Physics in Medicine and Biology from 2011-2020. Dr. Cherry was elected as a member of the National Academy of Engineering in 2016 and to the National Academy of Inventors in 2017.

March 18, 2022September 9, 2022

Exact Difference Schemes and Recent Advances in Coarse Mesh Methods for Thermal Hydraulics

SPEAKER:

Rizwan-uddin
Department of Nuclear, Plasma, and Radiological Engineering
University of Illinois at Urbana-Champaign

DATE/TIME:

FRI, 03/18/2022 - 3:00PM TO 4:00PM

LOCATION:

Zoom

Spring 2022 Colloquium Series

Abstract:

Roots of coarse mesh, or advanced, nodal methods [1] can be traced to “exact finite difference schemes.” After a brief overview of exact finite difference schemes, a nodal scheme will be developed for the scalar convection-diffusion PDE [2].

To address some of the limitations on classical nodal schemes, our efforts have focused on the development of: 1) a modified nodal method for the time-dependent Navier-Stokes (N-S) equations and its parallel implementation [3]; 2) methods for domains with curved boundaries [4, 5]; and 3) adaptive mesh refinement (AMR) capability for nodal schemes. The modified nodal method for the time-dependent, incompressible N-S equations incorporates two major modifications over nodal schemes developed earlier. First, rather than using the conventional continuity equation or the vorticity-stream function formulation, we replace the conventional continuity equation by a Poisson-type continuity equation written in terms of pressure, and retain the momentum equations in primitive variables. The second modification is introduced in the development of the numerical scheme. Here, rather than using only the diffusion term to obtain the homogeneous part of the solution of the momentum equations, a “linearized” convection term—based on previous time step velocity—is also retained on the left hand side of the transverse-integrated equations, leading to a local homogeneous solution for the transverse-integrated velocities in each spatial direction that is a combination of a constant, a linear and an exponential term.

Current work to remove the restrictions on domain geometry is focused on two approaches: 1) hybrid scheme in which nodal methods are restricted to the interior of the domains and along boundaries that are parallel to the coordinate axes, while a second scheme—such as finite element, more suitable for complex boundaries—is used along curved boundaries [4]; 2) iso-parametric mapping approach to transform the hexahedral elements to a simple cube on which traditional NIM can be applied [5].

1. R. D. Lawrence, “Progress in Nodal Methods for the Solution of the Neutron Diffusion and Transport Equations,” Progress in Nuclear Energy, 17 (3), 271 (1986).
2. Rizwan-uddin, “Comparison of the Nodal Integral Method and Non-Standard Finite-Difference Schemes for the Fisher Equation,” SIAM J. Scientific Computing, 22 (6), 1926-1942 (2001).
3. Fei Wang and Rizwan-uddin, “A Modified Nodal Scheme for the Time-Dependent, Incompressible Navier-Stokes Equations,” J. Comp. Physics, 187, 168-196 (2003).
4. Sundar Namala and Rizwan-uddin, "Hybrid Nodal Integral -Finite Element Method (NI-FEM) for 2D, Time-Dependent Burgers’ Equation in Arbitrary Geometries", Proc. of the Int. Topical Meeting on Nuclear Reactor Thermal Hydraulics, 3741-3755, Portland, OR, August 25-29, 2019.
5. Ibrahim Jarrah and Rizwan-uddin, "Nodal integral methods in general 2D curvilinear coordinates - applied to convection–diffusion equation in domains discretized using quadrilateral elements”, Int. J Heat and Mass Transfer 187 (2022) 122559, https://doi.org/10.1016/j.ijheatmasstransfer.2022.122559.

Virtual Education and Research Lab (VERL):
At VERL, we develop models to simulate physical phenomena, and solve them analytically and on high performance computers to simulate all aspects of processes taking place in and related to reactors and nuclear power plants (including neutronics, thermal hydraulics, etc). Recent focus has been on advanced numerical schemes for Computational Fluid Dynamics (CFD) as well as on multi-scale, multi-physics approaches achieved by coupling multiple codes. We also develop virtual, 3D, immersive and interactive models of facilities such as nuclear power plants, control rooms and laboratories, to help design better human-machine-interfaces, facilitate efficient design, and improve education and training. A recent addition to our portfolio is digital instrumentation and control and cyber security in the nuclear industry. This extension is being pursued in collaboration with the cyber security expertise available at the Coordinated Science Lab at the University of Illinois.

About the Speaker:

Dr Rizwan Uddin is Professor and Head of Nuclear, Plasma, and Radiological Engineering Department; Professor of Computational Science and Engineering; and Director of Master of Engineering in Energy Systems program at the University of Illinois at Urbana-Champaign. His areas of interest include thermal hydraulics; CFD; computational methods development; coupled neutronics and thermal hydraulics; biological systems and general modeling and simulation. With guidance from his undergraduate and graduate students, he has also been exploring the use of computer- and video-games for education and training. Recipient of numerous awards, he is also a fellow of the American Nuclear Society.

March 4, 2022February 22, 2022

Networked Radiation Detection in Urban Environments

SPEAKER:

Dr. Ren Cooper
Staff Applied Physicist
Lawrence Berkeley National Laboratory

DATE/TIME:

Fri, 03/04/2022 - 3:00PM TO 4:00PM

LOCATION:

3105 ETCHEVERRY HALL

Spring 2022 Colloquium Series

Abstract:

The ability to detect, identify, and localize illicit radiological/nuclear sources in urban environments is a key component of nuclear security and nuclear non-proliferation efforts across the world. Recent advances in sensing, telecommunications, and edge and cloud computing have led to renewed interest in employing detector networks to provide enhanced detection performance and increased domain awareness. This presentation will describe efforts to exploit multi-sensor fusion and networked sensing towards the development of new capabilities for radiation detection in urban environments.

About the Speaker:

Ren Cooper is a Staff Applied Physicist and Deputy Head of the Applied Nuclear Physics Program in the Nuclear Science Division at Lawrence Berkeley National Laboratory (LBNL). He received B.Sc., M.Sc., and Ph.D. degrees from The University of Liverpool, UK and joined LBNL in November 2011 following three years of postdoctoral research at Oak Ridge National Laboratory. Ren specializes in the development of novel radiation detection and imaging systems and algorithms for fundamental physics, nuclear safeguards, nuclear safety, and nuclear security. He currently leads research projects that include the development of new High Purity Germanium (HPGe) detectors, the development of advanced technologies for vehicle-based radiation detection and imaging systems, and the exploration of new systems and methods for networked radiation detection.

February 25, 2022February 24, 2022

Is Nuclear Clean?

SPEAKER:

Mary Lou Dunzik-Gougar

Ph.D. - Associate Professor, Associate Dean, Reactor Administrator, and American Nuclear Society President

DATE/TIME:

FRI, 02/25/2022 - 3:00PM TO 4:00PM

LOCATION:

zoom

Spring 2022 Colloquium Series

Abstract:

About the Speaker:

Dunzik-Gougar has a B.S. in chemistry from Cedar Crest College and received an M.S. in environmental engineering along with her Ph.D. in nuclear engineering from Pennsylvania State University. Her research interests include the nuclear fuel cycle, nuclear fuels and materials development, spent fuel processing, and waste form development.

In 2011 and 2014, she was the recipient of ANS Presidential Citations in addition to the Landis Public Communication and Education Award in 2014.

February 18, 2022March 15, 2022

For a Safer Nuclear Outlook: Learning from Experience within an Adaptive & Generic Probabilistic Safety Assessment Framework

SPEAKER:

Dr. Ali Ayoub

Postdoctoral Associate, Department of Nuclear Science and Engineering, Massachusetts Institute of Technology (MIT)

DATE/TIME:

Fri, 02/18/2022 - 3:00PM TO 4:00PM

LOCATION:

3105 ETCHEVERRY HALL

Spring 2022 Colloquium Series

Abstract:

The worldwide civil nuclear operations have accumulated more than 19’000 reactor-years of experience providing substantial amounts of data and knowledge. With the goal of more intensively learn from this experience to verify and improve the level of nuclear safety, this talk presents the research carried out at the ETH Zurich covering the following inter-woven parts:

1) The continued development and establishment of a novel open comprehensive nuclear events database; 2) subsequent event and statistical analysis to learn from the past and extract lessons, in particular, for 3) the development of generic & simplified Probabilistic Safety Assessment (PSA) models, with a main motivation of enabling large-scale precursor analysis, and 4) exploiting the simplified PSA models and the performed large scale precursor analyses to offer a comprehensive statistical study of the operational risk in the civil nuclear sector.

About the Speaker:

Dr. Ali Ayoub is currently a postdoctoral researcher at the Department of Nuclear Science and Engineering at the Massachusetts Institute of Technology (MIT). He received his PhD (2021) and MSc (2018) in Nuclear Engineering from the Swiss Federal Institute of Technology Zurich (ETH Zurich). He has worked and published on various research topics including probabilistic risk assessment (PRA), precursor analysis, uncertainty quantification, safety culture, and risk communication. His general research interests are around the area of risk analysis, nuclear and critical infrastructures safety, resilience engineering, decision-making, and energy policy.

February 4, 2022March 17, 2022

From Superheavy Elements to the Stockpile: The Journey of a Cal Grad

SPEAKER:

Dr. Sarah Nelson

DATE/TIME:

Fri, 02/04/2022 - 3:00PM TO 4:00PM

LOCATION:

zoom

Spring 2022 Colloquium Series

Abstract:

TBD

About the Speaker:

Dr. Sarah Nelson, a nuclear and radiochemist, serves as the Director (Acting) for the Office of Experimental Sciences for the National Nuclear Security Administration’s (NNSA) Office of Research, Development, Test, and Evaluation (NA-11), including Academic Programs. Sarah joined Defense Programs in mid-November 2015 as the office Deputy Director.

Sarah earned her bachelor’s degree in chemistry with Distinction from the University of California, Santa Barbara. She earned her doctorate in chemistry from the University of California, Berkeley with Professor Heino Nitsche.

Prior to joining NNSA, Sarah completed postdoctoral research as a Roger Batzel fellow at Lawrence Livermore National Laboratory, and afterward as a staff scientist for Pacific Northwest National Laboratory on assignment to the Defense Threat Reduction Agency. Sarah also was selected as a Christine Mirzayan Science & Technology Policy Fellow of The National Academies for the Winter 2012 assisting the Board on Physics and Astronomy.

She has received numerous awards including US DOE Secretary’s Achievement Award, DTRA/US STRATCOM Center for Combatting Weapons of Mass Destruction Director’s Award for Public Service, LLNL’s Excellence in Publication Award in Basic Science, and the Gordon Battelle Prize for Scientific Discovery.

January 28, 2022April 7, 2022

Recent inertial confinement fusion experiments at NIF reaching 1.35 MJ and the Lawson criterion for ignition

SPEAKER:

DR. ANDREA (ANNIE) L. KRITCHER

DATE/TIME:

FRI, 01/28/2022 - 3:00PM TO 4:00PM

LOCATION:

via Zoom

Spring 2022 Colloquium Series

Abstract:

The inertial fusion community have been working towards ignition for decades, since the idea of inertial confinement fusion (ICF) was first proposed by Nuckolls, et al., in 1972. On August 8, 2021, the Lawson criterion for ignition was finally demonstrated in the laboratory on the National Ignition Facility (NIF) in Northern California. The experiment, N210808, produced a fusion yield of 1.35 MJ from 1.9 MJ of laser energy and appears to have crossed the tipping-point of thermodynamic instability according to several ignition metrics. The “indirect” ICF approach at NIF described in this talk uses a hohlraum radiation cavity to heat and ablate the outside of a capsule that contains Deuterium-Tritium (DT) fusion fuel. This ablation causes the fuel to accelerate inward (implode) at high velocities doing work on a central lower density “hot spot” of DT fuel, increasing the temperature and density of the hot spot to the extreme conditions required for fusion. This presentation discusses the development of a platform that increased the hot-spot energy and hot-spot pressure, to achieve record ICF performance.

About the Speaker:

Dr. Annie Kritcher is the HYBRID-E design lead within the ICF program and is a member of the ICF leadership team. She serves as team lead for integrated implosion modeling and is a group leader within the design physics division at LLNL. Annie started at the Lab as a summer intern in 2004, was an LLNL Lawrence Scholar during her time at UC Berkeley, and was a Lawrence postdoctoral fellow in 2009 following completion of her Ph.D. Her current main areas of interest include the design and analysis of inertial confinement fusion experiments (ICF) and high energy density plasmas. She is also interested in extreme equations of state (EOS) measurements. Her work has led to both the highest fusion yields (>1.35 MJ) and the highest EOS measurements ever achieved in the laboratory.