PPPL-5308

Numerical Model of Dual-Coolant Lead-Lithium (DCLL) Blanket

Authors: A. Khodak, P. Titus, T. Brown, J. Klabacha

Abstract: The analysis of Dual-Coolant Lead-Lithium (DCLL) blankets requires application of Computational Fluid Dynamics (CFD) methods for electrically conductive liquids in geometrically complex regions and in the presence of a strong magnetic field. Several general-purpose CFD codes allow modeling of the flow in complex geometric regions, with simultaneous conjugated heat transfer analysis in liquid and surrounding solid parts. Together with a Magneto Hydro Dynamics (MHD) capability, the general purpose CFD is applicable or modeling of DCLL blankets. This presentation describes a numerical model based on the general purpose CFD code CFX from ANSYS customized to include MHD capability using a magnetic induction approach. Numerical model involves simultaneous modelling of two different liquids in different regions of the model: helium coolant, and lead lithium eutectic. Additionally neutron heating is included in the code using three dimensional heat source distribution mapped from the results of the Attila simulations. Surface heating of the front face of the blanket is also included. Geometry of the sample blanket is introduced directly from the CAD using step file. Most of the meshing was performed automatically using CFX mesher. Special grid generation methods were used to insure accurate resolution of the near wall boundary layers including several layers of large aspect ratio prismatic elements. DCLL design also includes some narrow flow regions between SiC insert and structure. These regions were meshed using sweep method two avoid high aspect ratio tetrahedral elements. The numerical model was tested against benchmarks specifically selected for liquid metal blanket applications, such as straight rectangular duct flows with Hartmann number of up to 15000. Results for a general three dimensional case of the DCLL blanket are also included.

Submitted to: Fusion Engineering and Design
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Download PPPL-5308 (pdf 2.6 MB 7 pp)
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