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Fusion Energy
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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2024 ANS Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
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Proving DRACO will deliver
The United States is now closer than it has been in over five decades to launching the first nuclear thermal rocket into space, thanks to DRACO—the Demonstration Rocket for Agile Cislunar Orbit.
Xiaoming Yang , Ran Liu, Li Zhang (CAPE)
Proceedings | Pacific Basin Nuclear Conference (2018 PBNC) | San Francisco, CA, September 30-October 4, 2018 | Pages 30-33
A simplified model with lumped parameters for mass, momentum and energy governing equations is usually used for thermal-hydraulic analysis during severe accident of a Nuclear Power Plant (NPP). In one of this kind of model, the flow in the flow path between two control volumes is usually simplified as one-dimensional pipe flow, and the extended expression of the Bernoulli Integral in the unsteady flow is used to solve the momentum governing equation correspondingly. It is noticed that the solution of the velocity in the flow field is very sensitive to the length of the streamline, so-called as inertia length introduced by the unsteady flow, corresponding to the inertia loss in the flow path.
Based on the theoretical model for the extended expression of the Bernoulli Integral in the unsteady flow, this paper shows the theoretical sensitivity analysis of the inertial length to the solution of the momentum governing equation firstly. According to the analysis, a sensitive study model for the inertia length was built by the thermal-hydraulic code, and the responses of the velocity, pressure and temperature versus different inertia lengths were studied. The results show that there is a slower time response of the fluid system states while the inertia length increases, and the thermal-hydraulic response is very sensitive to the inertia length of a flow path. Therefore, it is strongly recommended to choose the inertia length very carefully when dealing with the inertia response of the thermal-hydraulic system during severe accident analysis.