Fabbri, M.; de Blas, A.; Riego, A.; Dies, J.; Zamora, I.; Baeza, E. Fusion engineering and design Vol. 124, p. 1195-1198 DOI: 10.1016/j.fusengdes.2017.05.027 Data de publicació: 2017-11 Article en revista
tThe present work describes and supports the methodology for the improvement of the wall model devel-oped in AINA and its specific application to the Japanese DEMO Water Cooled Pebbled Bed. The set-upand application of this approach aims to obtain robust models by estimating the behavior of the studiedsystems as accurately as possible. These systems are represented in a simplified way. This requires thecomputation of a 3D radiation transport which has been carried out by means of MCNP6.1, ADVANTG andthermal-hydraulic calculations using ANSYS®Fluent®. Several CFD mesh typologies and discretizationshave also been employed to test the Richardson theorem. In addition, 1D simplified models have alsobeen created and optimized for their usage in AINA code. The temperature distribution also shows goodagreement (within 7%). In some cases the simplified models have not behaved in a conservative man-ner compared with the outcomes obtained for the 3D models. This observed absence of conservatism isintrinsic to the 1D approach. To cope with these effects, scaling functions have been determined as a ratiobetween the most conservative radial temperature distribution – computed by fully detailed 3D CFD –and the 1D simplified model. The scaling functions will be applied to the AINA computed wall tempera-ture distribution. To conclude, the determination and coherence of the result obtained using independenttools and approaches, ANSYS®Fluent®vs AINA thermal-hydraulic routines, lead us to recommend theproposed methodology.
Durante los últimos diez años, el código de seguridad AINA ha sido desarrollado con el objetivo de evaluar la evolución del plasma y los esfuerzos padecidos por los componentes internos de la vasija en distintos reactores de tipo Tokamak. El presente documento describe el nuevo código AINA 4 adaptado a los cuatro diseños europeos de DEMO (HCPB,DCLL, HCLL y WCLL).
Dicho código es fruto de una profunda y crítica revisión de las versiones anteriores y una nueva codificación donde nuevos modelos han sido implementados y muchos otros han sido modificados.
Tras esto, se puede concluir que AINA es actualmente una herramienta fiable, versátil y flexible a la hora de desarrollar estudios de seguridad.
Dichos estudios se basan en la evaluación de transitorios producidos tanto por la pérdida de control de plasma (LOPC) como por una pérdida de refrigerante (LOCA).
Las primeras simulaciones muestran deficiencias en el diseño de la vasija para la configuración HCPB del reactor DEMO. Estas carencias pueden tornarse muy relevantes en alguno de los
transitorios descritos conduciendo al reactor a un escenario de derretimiento de materiales.
A Roadmap to the realization of fusion energy was adopted by the EFDA system at the end of 2012. The roadmap aims at achieving all the necessary know-how to start the construction of a demonstration power plant (DEMO) by 2030, in order to reach the goal of fusion electricity in the grid by 2050. The roadmap has been articulated in eight different Missions. The present proposal has the goal of implementing the activities described in the Roadmap during Horizon 2020 through a joint programme of the members of the EUROfusion Consortium.
ITER is the key facility in the roadmap. Thus, ITER success remains the most important overarching objective of the programme and, in the present proposal the vast majority of resources in Horizon 2020 are devoted to ensure that ITER is built within scope, time and budget; its operation is properly prepared; and a new generation of scientists and engineers is properly educated (at undergraduate and PhD level) and trained (at postdoctoral level) for its exploitation. DEMO is the only step between ITER and a commercial fusion power plant. To achieve the goal of fusion electricity demonstration by 2050, DEMO construction has to begin in the early 2030s at the latest, to allow the start of operation in the early 2040s. DEMO cannot be defined and designed by research laboratories alone, but requires the full involvement of industry in all technological and systems aspects of the design. Specific provisions for the involvement of industry in the Consortium activities are envisaged.