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This division promotes the development and timely introduction of fusion energy as a sustainable energy source with favorable economic, environmental, and safety attributes. The division cooperates with other organizations on common issues of multidisciplinary fusion science and technology, conducts professional meetings, and disseminates technical information in support of these goals. Members focus on the assessment and resolution of critical developmental issues for practical fusion energy applications.
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June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
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Can hydrogen be the transportation fuel in an otherwise nuclear economy?
Let’s face it: The global economy should be powered primarily by nuclear power. And it probably will by the end of this century, with a still-significant assist from renewables and hydro. Once nuclear systems are dominant, the costs come down to where gas is now; and when carbon emissions are reduced to a small portion of their present state, it will become obvious that most other sources are only good in niche settings. I mean, why use small modular reactors to load-follow when they can just produce that power instead of buffering it?
Uuganbayar Otgonbaatar, Emilio Baglietto, Neil Todreas
Nuclear Science and Engineering | Volume 184 | Number 3 | November 2016 | Pages 430-440
Technical Paper | doi.org/10.13182/NSE16-9
Articles are hosted by Taylor and Francis Online.
The measurement of the steam generator feedwater mass flow rate is a dominant source of uncertainty in the nominal thermal power calculation of a plant. In this paper, mass flow rate measurement by means of an orifice plate is considered. Reynolds-averaged Navier-Stokes (RANS) simulation was performed using the computational fluid dynamics code STAR-CCM+ to quantify the representativeness uncertainty of mass flow rate measured in a dedicated experimental configuration. The representativeness uncertainty arises from applying the tolerance values prescribed by the International Organization for Standardization (ISO) standard in non-straight piping geometries. The simulation results were compared with the test results and the uncertainty bounds prescribed by the ISO standard, demonstrating the feasibility of applying RANS in an industrial setting for sub-1% uncertainty applications. The RANS results were also used to identify the variability in the measurement result with respect to the angular location of the pressure tap used in the flow rate measurement. Second, a large eddy simulation (LES) was performed on a straight piping configuration to simulate unsteady coherent flow shedding at the orifice plate. The spectral results of LES were compared with data from a test. The time-averaged LES results are within 0.1% of the value prescribed by the ISO standard. Direct comparison of the temporal spectrum of the LES result to the test data is not possible due to the measurement technique. This work is a part of a wider effort to develop a methodology to characterize, assess, and quantify representativeness uncertainty in performance indicator measurements of plants. Spatial, temporal, and modeling representativeness uncertainties are presented in this current work.