Featured Post from VCU College of Engineering

Researcher to build fuel database to improve nuclear reactor sustainability

Nov 17, 2022

3 min

Braden Goddard, Ph.D.Zeyun Wu, Ph.D.

Braden Goddard, Ph.D., assistant professor in the Department of Mechanical and Nuclear Engineering, has received a grant from the U.S. Department of Energy’s Nuclear Energy University Program (NEUP) to create a database for use in nuclear material control of pebble bed reactors (PBR).


Advances in material science and technology have revitalized the nuclear energy industry, allowing for the design and construction of advanced nuclear reactors. New high-temperature materials developed by researchers allow ideas from as early as 1970, like pebble bed reactors, to be re-explored and make nuclear power more efficient and sustainable.


Pebble bed reactors are one of many ideas from as early as 1970 that researchers are once again exploring to make nuclear power more efficient and sustainable now that science has developed new high-temperature materials.


“Imagine a gumball machine,” said Goddard, “A pebble bed reactor functions similarly. The pebbles are the gumballs, which are fed into a reservoir. As they make their way through the reactor, heat generated from the radiation is removed by a gas which then spins an electrical turbine to generate electricity. The pebbles then exit from the bottom of the reservoir and those that can be reused are returned to the top of the reservoir.”


Each pebble contains thousands of microscopic uranium particles encased in silicon-carbide cladding. As the pebble passes through the PBR, the path it follows affects how much fissioning occurs within the uranium. This means pebbles deplete at different rates based on how they travel through the reactor.


Goddard’s database seeks to characterize the state of a pebble after it leaves the PBR by determining precisely how much plutonium and uranium remains in the pebble. This informs PBR operators if the pebble can be reused or if it needs to be sent off as waste. Better characterizing these pebbles improves the sustainability and security of PBRs while reducing the amount of waste generated.


Measuring gamma radiation from the radioactive isotope cesium-137 created from the fission of uranium is the traditional method of determining how much nuclear fuel is still viable. However, this system does not work for PBRs because the correlation between the uranium fuel and the gamma radiation it emits is not consistent between pebbles. To remedy this, Goddard will measure both gamma and neutron radiation emitted by all radioactive isotopes in the pebble, which varies depending on the route the pebble takes through the reactor. Partners like Brookhaven National Laboratory and similar institutions within the United States will assist in the research by applying machine learning techniques to the gamma and neutron radiation signature.


“Nuclear reactor operators have instruments that tell them what’s going on inside the reactor, but it’s not the same as knowing how much uranium mass you have in fuel going into or coming out of the reactor,” said Goddard.


Goddard and his colleague, Zeyun Wu, Ph.D., will use computer modeling to run countless simulations and map every possible course a pebble can take through a PBR. The resulting catalog of data will allow PBR operators to characterize the state of any pebble leaving the PBR and assess if it can be reused or if it is ready to be stored at a nuclear waste facility. The catalog also serves as a material inventory, allowing nuclear facilities to better track waste material.

Connect with:
Braden Goddard, Ph.D.

Braden Goddard, Ph.D.

Associate Professor, Department of Mechanical and Nuclear Engineering

Professor Goddard is a nuclear engineer specializing in nuclear security and nonproliferation.

Nuclear security and counter terrorismNonproliferation and international safeguardsRadiation detection and measurementsEnvironmental measurements and assay
Zeyun Wu, Ph.D.

Zeyun Wu, Ph.D.

Associate Professor, Department of Mechanical and Nuclear Engineering

Reactor physics, computational methods, sensitivity and uncertainty analysis, advanced data analytics, machine learning

Reactor PhysicsReactor core design and analysisComputational method for neutron transportUncertainty and sensitivity analysisAdvanced data analytics
Powered by

You might also like...

Check out some other posts from VCU College of Engineering

National Science Foundation funds research into quantum material-based computing architecture at the VCU College of Engineering featured image

2 min

National Science Foundation funds research into quantum material-based computing architecture at the VCU College of Engineering

Supporting the development of advanced computing hardware, the National Science Foundation (NSF) awarded Supriyo Bandyopadhyay, Ph.D., Commonwealth Professor in the Department of Electrical and Computer Engineering at the Virginia Commonwealth University (VCU) College of Engineering with more than $300,000 to develop processor-in-memory architecture using quantum materials. “This is one of the first mainstream applications of quantum materials that have unusual and unique quantum mechanical properties,” Bandyopadhyay said. “Quantum materials have been researched for more than a decade and yet there is not a single mainstream product in the market that utilizes them. We want to change that.” The four-year project, titled “Collaborative Research, Foundations of Emerging Technologies: PRocessor In Memory Architecture based on Topological Electronics (PRIMATE),” aims to advance computing hardware and artificial intelligence by integrating topological insulators and magnetic materials. Topological insulators are a special material with an electrically conductive surface and an insulated interior. They have special quantum mechanical properties like “spin-momentum locking,” which ensures the quantum mechanical spin of an electron-conducting current on the surface of the material is always perpendicular to the direction of motion.This marks the first time such quantum materials will be used in a processor-in-memory system. “We place a magnet on top of a topological insulator,” Bandyopadhyay said. “We then change the magnetization of the magnet by applying mechanical strain on it. That changes the electrical properties of the topological insulator via a quantum mechanical interaction known as exchange interaction. This change in the electrical properties can be exploited to perform the functions of a processor-in-memory computer architecture. The advantage is that this process is fast and extremely energy-efficient.” If successful, this approach could reduce energy use and dramatically speed up computing by moving data processing into the memory itself. It addresses the longstanding “memory bottleneck,” the slowdown caused by computers constantly needing to move data back and forth between processor and memory. These efficiencies could make advanced AI more efficient and accessible, paving the way for the first commercially viable applications of quantum materials.. The research is a collaboration with University of Virginia professors Avik Ghosh and Joseph Poon. A VCU Ph.D. student will work on the project and receive training in fabrication, characterization and measurement techniques, preparing them to lead in the rapidly evolving field of computing hardware.

American Nuclear Society names Lane Carasik, Ph.D., as one of its “40 Under 40” featured image

2 min

American Nuclear Society names Lane Carasik, Ph.D., as one of its “40 Under 40”

Recognized as an emerging leader in the nuclear science and engineering field, Lane Carasik, Ph.D., assistant professor in the Department of Mechanical and Nuclear Engineering, was recently acknowledged by the American Nuclear Society as one of its top “40 Under 40.” “It is a huge honor to receive this acknowledgement from my professional community,” said Carasik. “I feel it is a reflection of the amazing nuclear engineering activities I’ve gotten the opportunity to pursue before and during my time at the VCU College of Engineering.” The list, featured in the most recent issue of Nuclear News magazine, celebrates young professionals who are driving innovation and shaping the future of nuclear science and technology. Created to spotlight a new generation of nuclear professionals, the “40 Under 40” program highlights those who are advancing technical fields, from advanced reactor deployment to AI applications and national security, while actively engaging the public, mentoring peers and advocating for nuclear’s role to achieve energy independence and security. “Dr. Carasik’s research efforts, together with his support for students and their own research goals, exemplifies the best qualities of the VCU College of Engineering,” said Arvind Agarwal, Ph.D., chair of the Department of Mechanical and Nuclear Engineering, “integrating research and teaching at the core of everything he does, from classroom and lab work to community outreach.” Carasik was selected for the “40 Under 40” from hundreds of candidates across the United States. Mentoring his first three Ph.D. graduates, Arturo Cabral, Connor Donlan and James Vulcanoff, is one of Carasik’s proudest achievements. He was also honored by the American Society of Mechanical Engineers (ASME) as a rising star in mechanical engineering in 2024 This builds off Carasik receiving the highly competitive and prestigious Department of Energy (DOE) Early Career Research Award ($875k split over five years) in 2023 to support his work on molten salt based fusion energy systems similar to Commonwealth Fusion Systems’ ARC technology. Carasik’s Fluids in Advanced Systems and Technology (FAST) research group, is a computational and experimental thermal hydraulics group focused on enabling the development of advanced energy systems and critical isotope production methods. Legendary physicist Enrico Fermi was an early inspiration to Carasik during his undergraduate studies. Fermi’s expertise mirrored Carasik’s interests, and the physicist’s impact on the field of nuclear engineering was motivating. As an established nuclear engineering faculty member, Carasik seeks to make a lasting impact on the field and the people in it. His ’s long-term goal is earning membership in the National Academies of Sciences, Engineering and Medicine.

VCU College of Engineering’s Michael McClure, Ph.D., named chair of Orthopaedic Research Society’s Skeletal Muscle Section featured image

2 min

VCU College of Engineering’s Michael McClure, Ph.D., named chair of Orthopaedic Research Society’s Skeletal Muscle Section

Michael McClure, Ph.D., associate professor from the Department of Biomedical Engineering and affiliate faculty in the Department of Orthopaedic Surgery and in the Institute for Engineering and Medicine, has been named chair of the Orthopaedic Research Society’s (ORS) newly launched Skeletal Muscle Section. The section began in August 2025, building on research interest groups and symposia to create a dedicated home for skeletal muscle studies within ORS. Its mission is to advance collaboration, innovation, education and translation in this field. Skeletal muscle disorders cause disability, chronic pain and high health care costs. Severe injuries and degenerative diseases, such as muscular dystrophies, remain difficult to treat. The section will strengthen research in muscle development, aging, trauma, disuse and disease. This work will expand the basic understanding of and identify therapeutic targets to restore function. In its first year, the section will measure success through increased skeletal muscle abstracts at the 2027 ORS Annual Meeting, growth in ORS membership and active participation in section programs. “We are thrilled to launch the Skeletal Muscle Section,” McClure said. “This home for translational muscle research will build on ORS progress over the past 10 years, help recruit new members and foster an environment that connects multiple areas of orthopaedic science.” McClure’s commitment to this work is shaped by his family’s experience with neuromuscular diseases, witnessing the impact of war-related injuries on patients’ quality of life from the Richmond Veterans Affairs Medical Center, and the momentum of translational discovery. Learn more about the ORS Skeletal Muscle Section.

View all posts
Powered by