In EU DEMO reactor, components exposed to burning plasma are subject to extreme conditions due to short and extremely strong thermal transients, which impact their lifetime and functional integrity. Due to this energy, surface vaporization, melting and resolidification may lead to excessive degradation and frequent extraordinary maintenance. For this reason, in view of DEMO and future reactors, one of the most challenging aspects of fusion reactor technology is to devise FW (First Wall) sacrificial limiters that will prevent excessive damage of the otherwise un-shadowed FW modules during extreme plasma transients. Rather than dense armours, W-lattice structures can contribute to this purpose, since they can be optimized to have a thermal conductivity that ensures, at steady state, effective heat dissipation and at the same time a thermal diffusivity that, in transients, maximizes the vapour shielding effect. The objective of the research activity here presented was to identify, through a parametric model, the optimized component configurations to be considered for this sacrificial limiter, in order to maximize its functional effectiveness. Based on the two elementary cell morphologies developed in previous studies, the parametric model allowed to investigate the combinations of relevant parameters, above all component size and geometries, armour/heat sink materials and thicknesses. Thermal optimization regarded both normal operation and two possible transient scenarios: an unmitigated plasma disruption or the Ramp Down phase. By scanning all possible combinations of parameters, those able to provide the best performances thus satisfying the user-defined functional requirements of the limiter have been identified. The thermal optimization phase was followed by CFD (Computational Fluid Dynamics) analyses in order to evaluate the potential integration of the limiter cooling circuits within the divertor Primary Heat Transfer System (PHTS) from a thermal–hydraulic point of view.
Stefanini, C., Fanelli, P., De Luca, R., Paoletti, D., Vivio, F., Belardi, V., et al. (2023). Parametric FE model for the thermal and hydraulic optimization of a Plasma Facing Component equipped with sacrificial lattice armours for First Wall limiter application in EU-DEMO fusion reactor. FUSION ENGINEERING AND DESIGN, 192 [10.1016/j.fusengdes.2023.113604].
Parametric FE model for the thermal and hydraulic optimization of a Plasma Facing Component equipped with sacrificial lattice armours for First Wall limiter application in EU-DEMO fusion reactor
Vivio F.;Belardi V.;Trupiano S.;
2023-01-01
Abstract
In EU DEMO reactor, components exposed to burning plasma are subject to extreme conditions due to short and extremely strong thermal transients, which impact their lifetime and functional integrity. Due to this energy, surface vaporization, melting and resolidification may lead to excessive degradation and frequent extraordinary maintenance. For this reason, in view of DEMO and future reactors, one of the most challenging aspects of fusion reactor technology is to devise FW (First Wall) sacrificial limiters that will prevent excessive damage of the otherwise un-shadowed FW modules during extreme plasma transients. Rather than dense armours, W-lattice structures can contribute to this purpose, since they can be optimized to have a thermal conductivity that ensures, at steady state, effective heat dissipation and at the same time a thermal diffusivity that, in transients, maximizes the vapour shielding effect. The objective of the research activity here presented was to identify, through a parametric model, the optimized component configurations to be considered for this sacrificial limiter, in order to maximize its functional effectiveness. Based on the two elementary cell morphologies developed in previous studies, the parametric model allowed to investigate the combinations of relevant parameters, above all component size and geometries, armour/heat sink materials and thicknesses. Thermal optimization regarded both normal operation and two possible transient scenarios: an unmitigated plasma disruption or the Ramp Down phase. By scanning all possible combinations of parameters, those able to provide the best performances thus satisfying the user-defined functional requirements of the limiter have been identified. The thermal optimization phase was followed by CFD (Computational Fluid Dynamics) analyses in order to evaluate the potential integration of the limiter cooling circuits within the divertor Primary Heat Transfer System (PHTS) from a thermal–hydraulic point of view.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
