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NRC looks to leverage previous approvals for large LWRs
During this time of resurging interest in nuclear power, many conversations have centered on one fundamental problem: Electricity is needed now, but nuclear projects (in recent decades) have taken many years to get permitted and built.
In the past few years, a bevy of new strategies have been pursued to fix this problem. Workforce programs that seek to laterally transition skilled people from other industries, plans to reuse the transmission infrastructure at shuttered coal sites, efforts to restart plants like Palisades or Duane Arnold, new reactor designs that build on the legacy of research done in the early days of atomic power—all of these plans share a common throughline: leveraging work already done instead of starting over from square one to get new plants designed and built.
Byeong-Il Jang, Moo Hwan Kim, Gyoodong Jeun
Nuclear Technology | Volume 177 | Number 2 | February 2012 | Pages 203-216
Technical Paper | Thermal Hydraulics | doi.org/10.13182/NT12-A13366
Articles are hosted by Taylor and Francis Online.
Research regarding small- and medium-sized nuclear reactors (SMRs) has increased because of multipurpose applications and increased safety. According to this tendency, a new conceptual nuclear reactor, the Regional Energy rX-10MWt (REX-10), is being designed. REX-10 adopts a way to remove heat by natural circulation and integrates the primary systems within a reactor pressure vessel. To evaluate the steady-state and transient behavior of natural circulation in REX-10, a NAtural Circulation TEst Reactor (NACTER) is designed using the scaling law. The ratio of the height and core power are 1/3 and 1/500, respectively.This research can be divided into three parts - a steady-state experiment, a transient experiment, and MARS (Multidimensional Analysis for Research Safety) code analysis. To investigate the natural circulation characteristics under the steady-state conditions, two parameters were chosen and various experiments were conducted. As a result of the steady-state experiment, we show that the most important parameter that affects the natural circulation behavior is the heater power. In addition, we carried out a transient experiment. The results of the transient experiment are that the NACTER facility is well controlled and guarantees safety in abrupt changes in experimental conditions. Finally, MARS code simulations were conducted. The MARS code results show good agreement with the experimental results.
