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Nuclear Science and Engineering
Fusion Science and Technology
The consequences of closure: The local cost of shutting down a nuclear power plant
When on May 7, 2013, the Kewaunee nuclear power plant in rural Wisconsin was shut down, it took with it more than 600 full-time jobs and more than $70 million in lost wages, not including temporary employment from refueling and maintenance outages. Taking into account indirect business-to-business activity, the total economic impact of the closure of the single-unit pressurized water reactor was estimated to be more than $630 million to the surrounding three-county area.
Sunming Qin, Victor Petrov, Annalisa Manera
Nuclear Science and Engineering | Volume 194 | Number 8 | August-September 2020 | Pages 583-597
Technical Paper | dx.doi.org/10.1080/00295639.2020.1755805
Articles are hosted by Taylor and Francis Online.
Results reported in the literature have shown that the turbulence models currently implemented in computational fluid dynamics (CFD) commercial codes (e.g., ANSYS-CFX, STAR-CCM+, and FLUENT) have a tendency to overestimate thermal stratification and underestimate turbulent mixing when buoyancy effects become dominant with respect to momentum effects. Also, standard large eddy simulation models cannot fully capture the behavior of jets interacting with stratified environments because the assumption of turbulence isotropy of the smaller scales breaks down. Because of light diffraction and image distortion, it is challenging to apply nonintrusive optical flow measurements, like particle image velocimetry (PIV) and planar laser-induced fluorescence (PLIF), to get experimental data for CFD validations when there are density variances involved in the flow. However, a refractive index matching (RIM) technique that has been recently developed in our Experimental and Computational Multiphase Flow Laboratory allows us to perform high-resolution measurements of velocity fields and scalar fields for turbulent buoyant jet flow in the presence of density differences as high as 8.6%.
To form a fully turbulent round free jet, an experimental facility was designed with a jet nozzle diameter of 2 mm, located at the bottom of a cubic tank with 30-cm side length. The jet flow is established by a servo-engine-driven piston to eliminate possible fluctuations introduced by the motor. A high-fidelity synchronized PIV/PLIF system was utilized in conjunction with RIM to measure the velocity and concentration fields in the self-similar regions of a jet flow with a density difference of 3.16% for aqueous solutions. With Reynolds numbers of 4000 and 10 000, the jet impinging with a two-layer stably stratified environment is compared to the positively buoyant jet with lighter fluid injected into denser surroundings. Detailed quantifications of the measurement uncertainties are also carried out. The experimental results are presented in terms of turbulent statistics and the analysis of jet penetration depths.