Method and system for solving core sub-channel coupling model, storage medium and application

Abstract

This invention relates to the field of advanced nuclear reactor thermal-hydraulic analysis and multiphysics coupling calculation technology, specifically to a solution method, system, storage medium, and application for core subchannel coupling models. The method establishes a fully implicit discrete core subchannel coupling model and corresponding global nonlinear residual equations based on a drift flow model. It proposes a globally unified solution method combining fixed-point iteration with a Jacobi-Newton-Krylov solution. During the solution process, the global solution vector is first updated using fixed-point iteration to obtain the predicted solution, and a switching criterion is constructed based on the iteration increments of adjacent fixed points. When the switching condition is met, the fixed-point iteration operator is introduced as a physical preprocessing step into the Jacobi-Newton-Krylov solution framework. The solution is then completed by combining the Jacobi-vector product approximation constructed using finite-difference perturbation, the Krylov subspace iteration method, and a line search strategy, yielding the core thermal-hydraulic parameter distribution and effectively improving the stability and efficiency of the fully implicit solution of the core subchannel coupling model.

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