Evaluation of interface capturing schemes for two-phase flow in a rod bundle

Fukuda, Takanari ; Uesawa, Shinichiro  ; Yamashita, Susumu   

A comparative study was conducted on three interface capturing schemes (ICSs) of the VOF method: THINC/WLIC, THINC/AWLIC, and PLIC for simulating gas-liquid two-phase flow in a BWR reactor core. The simulations in a rod bundle geometry were compared qualitatively and quantitatively with experimental data obtained with a high-speed camera and wire mesh sensors. The results showed that the all ICSs yielded reasonable agreements with experimental data, but THINC/WLIC had a significant issue in which the VOF value diffuses and dissipates over the simulation geometry. THINC/AWLIC, developed by the authors, improved the VOF diffusion issue of the THINC/WLIC and predicted the void fraction close to that of the highly accurate ICS of PLIC, despite its simpler algorithm. However, the numerical bubble coalescence was still an issue, particularly at low gas flow rates, which calls for further research to refine the simulation results to better reflect actual bubble behavior.