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Conference Spotlight
2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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Shifting the paradigm of supply chain
Chad Wolf
When I began my nuclear career, I was coached up in the nuclear energy culture of the day to “run silent, run deep,” a mindset rooted in the U.S. Navy’s submarine philosophy. That was the norm—until Fukushima.
The nuclear renaissance that many had envisioned hit a wall. The focus shifted from expansion to survival. Many utility communications efforts pivoted from silence to broadcast, showcasing nuclear energy’s elegance and reliability. Nevertheless, despite being clean baseload 24/7 power that delivered a 90 percent capacity factor or higher, nuclear energy was painted as risky and expensive (alongside energy policies and incentives that favored renewables).
Economics became a driving force threatening to shutter nuclear power. The Delivering the Nuclear Promise initiative launched in 2015 challenged the industry to sustain high performance yet cut costs by up to 30 percent.
T. Courau, G. Marleau
Nuclear Science and Engineering | Volume 143 | Number 1 | January 2003 | Pages 19-32
Technical Paper | doi.org/10.13182/NSE02-11
Articles are hosted by Taylor and Francis Online.
Generalized perturbation theory (GPT) can be used as a means to evaluate sensitivity coefficients or to approximate variations in integrated lattice parameters resulting from small changes in local cell properties. Using a first-order perturbation approach, the changes in the integral parameters can be written as a sum of a direct term that takes directly into account the variations in the cell properties and an indirect term that approximates the neutron flux variations resulting from the perturbation. For a lattice cell code that relies on a collision probability technique to solve the transport equation, a problem related to the evaluation of the perturbed transport operator also arises because the collision probability matrix depends on the total cross section. A technique is presented to simulate these variations in the collision probability matrix using approximate source term variations. Comparison with exact calculations will show that the results obtained using GPT with these approximate source terms are reliable provided the perturbations remain small. Results for a parametric study of a two-dimensional pressurized water reactor 17 × 17 assembly and void reactivity calculations for a DUPIC-fueled CANDU cell are also presented.
