Cell-wise static coupling calculation of a new neutronics/thermal-hydraulics coupling benchmark for plate-type PWR core

• A new cell-wise neutronics/thermal-hydraulics coupling benchmark for high parameter plate-type PWR. • Four codes participated in calculations of the phase II of COPHP, the results showed good agreement. • The local high void fraction is a key factor influencing discrepancies in k eff and power distribution among the codes. • The accuracy of two-phase flow modeling is essential for reliably simulating high-parameter cases in the COPHP. To support the verification of cell-wise neutronics/thermal hydraulics (N-TH) coupling codes for Pressurized Water Reactor (PWR), the Nuclear Power Institute of China (NPIC) collaborated with multiple research institutions in the nuclear energy field to design and develop COPHP, a high-parameter PWR full core cell-wise N-TH coupling benchmark. This paper elaborates on Part II of the benchmark—cell-wise static N-TH coupling—including case design, modeling, results, and deviation analysis. Key conclusions are as follows: 1) Consistency was observed among the results from four participating codes (RMC/CORTH-R, OpenMC, CORCA-SPn/CORTH-R, and CORCA-SPn/TH1D) across 32 cases covering two core configurations. 2) Compared to RMC/CORTH-R: OpenMC exhibited a maximum k eff deviation of −29.6 pcm and a maximum cell-wise power weighting error (PWE) of 0.185 %; CORCA-SPn/CORTH-R showed a maximum k eff deviation of −474.6 pcm and a maximum PWE of 3.179 %; CORCA-SPn/TH1D yielded a maximum k eff deviation of 1310.4 pcm and a maximum PWE of 5.245 %. 3) Two-phase flow at the core outlet in some cases of COPHP-B significantly affected the N-TH coupling results of CORCA-SPn/TH1D. 4) This benchmark suite provides comprehensive results for high-fidelity N-TH coupling in high-parameter PWRs, catering to diverse validation needs.