Numerical Simulation of Heat Transfer Characteristics of 2×2 Wire-Wrap Rod Bundles under Supercritical Conditions

The SCWR assembly always adopts the tight lattice configure with the wire wrap to fix up. The wire wrap will contribute the turbulent mixing in different subchannels and have big impact on the heat transfer characteristics in the rod bundles. This paper took the small wire-wrap 2×2 rod bundles as the analysis object and investigated the heat transfer phenomena with the CFD tools. It was found that the wire wrap will enhance the heat transfer capability and impair the non uniformity of wall temperature. However, it could also bring about the local wall peak temperature which could be classified into two reasons. The impact of wire wrap structure parameter on heat transfer was also explained.