Speaker
Marco Fabbri
(Fusion Energy Engineering Laboratory)
Description
For almost ten years now, several safety studies of plasma-wall transients have been performed with AINA code for ITER, the European DEMO design (e.g. HCPB) and Japanese one (e.g. Water Cooled Pebbled Bed or WCPB) to establish an envelope for the worst effects of ex-vessel LOCA and overfuelling. For this purpose, for each blanket type a specific wall-model has been developed for different AINA code versions adapting also the plasma features if necessary. The implementation of a robust, conservative and optimized wall-model plays a key role in obtaining reliable and time achievable thermo-hydraulic results. The plasma facing components, up to the Vacuum Vessel Inner shell, are discretized in the poloidal coordinates according to the number of blanket and divertor regions. They are independent elements linked by radiation heat process. In each zone the thermal evolution (both steady state and transient) is determined and used as input to the plasma model to estimate for instance the erosion fluxes. At the same time, the materials temperatures have a not-negligible impact on the nuclear deposition (or NHD), due the density variation and the Doppler effect broadening which is being determined by means of MCNP and NJOY. The NHD has been parametrized in function of temperature, poloidal coordinates, accident type, material temperature and radial distance. The thermo-hydraulic problem is obviously iterative and very computationally demanding. For this reason, the 1D/2D models are obtained and implemented in AINA starting from a detailed 3D model. The solvers are based on multigrid algorithm over a finite volume scheme. Temperature adjusting coefficients are implemented to maintain the temperature peaks. Also, independent verifications of the wall thermal behavior have been performed using ANSYS-Fluent©. This poster aims to describe, mainly, the improvement in wall model generation process for the Japanese DEMO-WCPB options since the last AINA release.
Co-authors
Albert Riego
(Fusion Energy Engineering Laboratory, Universidad Politecnica de Calatunya, Av. Diagonal 647, Pav. C, 08028 Barcelona, Spain, Spain)
Alfredo De Blas
(Fusion Energy Engineering Laboratory, Universidad Politecnica de Calatunya, Av. Diagonal 647, Pav. C, 08028 Barcelona, Spain, Spain)
Edu Baeza
(Fusion Energy Engineering Laboratory, Universidad Politecnica de Calatunya, Av. Diagonal 647, Pav. C, 08028 Barcelona, Spain, Spain)
Imanol Zamora
(Fusion Energy Engineering Laboratory, Universidad Politecnica de Calatunya, Av. Diagonal 647, Pav. C, 08028 Barcelona, Spain, Spain)
Javier Dies
(Fusion Energy Engineering Laboratory, Universidad Politecnica de Calatunya, Av. Diagonal 647, Pav. C, 08028 Barcelona, Spain, Spain)
Marco Fabbri
(Fusion Energy Engineering Laboratory, Universidad Politecnica de Calatunya, Av. Diagonal 647, Pav. C, 08028 Barcelona, Spain, Spain)
