Validation and Typical Application of Thermal-hydraulic Code Analysis in Numerical Reactor with CVR-PACA Code

Spectral element method (SEM) is a high-order numerical method. A high-precision parallel CFD code CVR-PACA for thermal-hydraulic analysis of numerical reactor was developed by using this method. In this paper, CVR-PACA was employed to model and predict turbulent flow in single bare rod, 3×3 bare rod bundle, Matis-H benchmark and 19 wire-wrapped rod bundle, aiming to validate the predicting capability of large eddy simulation (LES) model and unsteady Reynolds-averaged (URANS) model within the typical applications of thermal-hydraulic analysis in fuel assembly of reactor core. Spatial discretization for complicated geometries was also achieved with full-hexahedral mesh using mesh splitting method. Much more modeling experience of high-precision CFD code CVR-PACA were accumulated during the calculation processes and abundant flow and heat transfer details in various rod bundle channels were obtained, while result from CVR-PACA could provide more thermal-hydraulic details for design optimization.