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NN Asks: What hurdles stand in the way of nuclear power’s global expansion?
Jake Jurewicz
Nuclear technology is mature. It provides firm power at scale with minimal externalities and has done so for decades. The core problem isn’t about the technology—it is how the plants are built. Nuclear construction has a well-documented history of cost and schedule overruns. Previous nuclear plants often spent more than twice what was first budgeted, making nuclear among the power technologies with the largest average cost overruns worldwide.
Recent projects illustrate how severe the problem can be. In South Carolina, the V.C. Summer nuclear expansion saw projected costs rise from roughly $10 billion to more than $25 billion before the project was abandoned in 2017, by which time more than $9 billion had already been spent and customers were stuck paying for a site they have yet to benefit from.
Ryuji Yoshikawa, Yasutomo Imai, Norihiro Kikuchi, Masaaki Tanaka, Hiroyuki Ohshima
Nuclear Technology | Volume 210 | Number 5 | May 2024 | Pages 814-835
Research Article | doi.org/10.1080/00295450.2023.2249707
Articles are hosted by Taylor and Francis Online.
In the study of safety enhancements on advanced sodium-cooled fast reactors (SFRs) by the Japan Atomic Energy Agency (JAEA), it has been essential to clarify the thermal hydraulics under various operating conditions at high and low flow rate conditions in a fuel assembly (FA) with wire-wrapped fuel pins to assess the structural integrity of the fuel pin that achieves a high-performance core with high burnup ratio and high power density. A finite element thermal-hydraulic analysis code named SPIRAL has been developed by JAEA to analyze the detailed thermal-hydraulic phenomena in the FA of a SFR.
In this study, numerical simulations of 37-pin bundle sodium experiments at different Reynolds (Re) number conditions, including a transitional condition between laminar and turbulent flows and turbulent flow conditions, were performed to validate the developed hybrid k-ε/kθ-εθ turbulence model equipped in SPIRAL to consider the low Re number effect near the wall in the flow and temperature fields. The temperature distributions predicted by SPIRAL were consistent with those measured in the sodium experiments at the Re number conditions. Through the validation study, the applicability of the hybrid turbulence model in SPIRAL to the thermal-hydraulic evaluation of sodium-cooled FAs in a wide range of Re numbers was confirmed.
