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A trip abroad
Hash Hashemian president@ans.org
In my August column in Nuclear News, I reflected on the importance of ANS’s annual conferences for bringing together our nuclear community at the national level. In September, after speaking at Tennessee’s Nuclear Opportunities Workshop, I focused my NN column that month on the value of state-level conferences.
Also in September, alongside ANS Executive Director/CEO Craig Piercy, I shifted my focus to another key front in nuclear collaboration, the international stage, by attending the General Conference of the International Atomic Energy Agency in Vienna.
The timing of the IAEA’s General Conference could not have been better; it took place the same week the U.S. and U.K. kicked off a new wave of transatlantic partnerships in the nuclear sector between both government and industry. This fortuitous overlapping gave us a timely and concrete reminder of international collaboration’s unparalleled benefits.
The General Conference was an expectedly busy event. To cover as much ground as possible, Piercy and I took turns attending either the U.S. delegation meetings with other countries or the General Assembly of the IAEA, where the American Nuclear Society has a seat among other critical nongovernmental organizations.
We listened to presentations by several of the 180 IAEA member states, including, of course, the United States. Aside from ANS, the U.S. presence at the conference included U.S. Secretary of Energy Chris Wright, NRC Chair David Wright, and DOE Assistant Secretary of Nuclear Energy Ted Garrish.
U.S. representation was further bolstered by an industry delegation that included 65 participants from 32 companies, many of whom used the opportunity to report progress on their plans for the international expansion of their nuclear fleets. Meetings of that industry delegation were coordinated by the Nuclear Energy Institute.
Aside from the main conference, Piercy and I also attended the embedded meetings of the International Nuclear Society Council. INSC exists to facilitate knowledge-sharing and collaboration between 18 different member nuclear societies from around the world.
The INSC meetings within the General Conference brought together the presidents and senior members of those societies to give presentations and explore new opportunities. I made a presentation on the state of nuclear in North America, covering the latest developments and deployments in the U.S. and Canada.
This presentation emphasized the new nuclear lift in the U.S. that is being heavily supported by the Trump administration. I recapped the four executive orders issued by President Trump in May, the recent momentum at the DOE, and how these changes are capitalizing on a broader groundswell in both industry development and public support.
I also pointed out the success of our neighbor Canada in progressing on the first water-cooled small modular reactor in North America using BWRX-300 technology, which was supplied by an American firm and international partners—a perfect symbol of the value of global nuclear collaboration.
In all, I have now represented ANS at the state, national, and international levels, gaining useful insight into the work that needs to be done at each. From this vantage point, it’s clear to me that the path forward from the country to the globe is to, above all else, keep working together and supporting each other to bring about the next age of nuclear.
Nicholas A. Meehan, Seok Bin Seo, Trevor K. Howard, Nicholas R. Brown
Nuclear Technology | Volume 209 | Number 8 | August 2023 | Pages 1164-1188
Research Article | doi.org/10.1080/00295450.2023.2195355
Articles are hosted by Taylor and Francis Online.
A reactivity-initiated accident (RIA) is a design-basis accident under which critical heat flux (CHF) is likely to be exceeded. The operational margin for RIAs is currently determined using steady-state CHF lookup tables, which provide conservative estimates relative to transient CHF phenomena. The Transient Reactor Test Loop (TRTL) facility at Oregon State University is capable of performing out-of-pile rapid heating experiments representative of a RIA at conditions representative of a pressurized water reactor (PWR). To further our understanding of and ability to predict transient CHF under PWR conditions, we performed a sensitivity analysis on a RELAP5-3D model of the TRTL facility coupled to the RAVEN code framework to define a proposed experimental test matrix to be performed at the TRTL facility. We then implemented a flow boiling CHF correlation into RELAP5-3D and performed a secondary sensitivity analysis inspecting the impact of the built-in RELAP5-3D CHF and heat transfer multipliers on both the prediction of CHF and key safety parameters, such as peak cladding temperature and heat flux. The results show that the multiplier with the highest influence toward the prediction of CHF occurrence and the safety parameters is the transient CHF multiplier. Operational performance envelopes have been developed for each of the test matrix cases and will be used for validation once the experiments are performed. The TRTL facility is currently performing shakedown testing to verify system performance prior to proceeding with the experimental campaign. Restart testing results include pump curve restart testing, pressure tests, and heater rod thermocouple transients.