Experiments and analysis on LBE steady natural circulation in a rectangular shape loop

For the purpose of investigating the thermal-hydraulic characteristics of lead-bismuth eutectic (LBE) natural circulation (NC), a LBE NC loop (NC-loop), experimental platform of the KYLIN-II facility was operated by the Institute of Nuclear Energy Safety Technology (INEST) in 2011. Experiments to characterize the thermal-hydraulic performance of HLM coolants undergoing NC were carried out at steady state to study the following issues: 1) the initiation of NC at different power levels; 2) the effects of input power and secondary loop operational characteristics on NC; 3) the capacity limits of NC and 4) a comparison of experimental data with theoretical predictions. The maximum NC capacity for LBE with a flow rate of 1.2 kg/s was obtained for a 24 kW heat pin corresponding to heating power input of 200 W/cm, which is higher than the linear power rating of the proposed China LEad Alloy Reactor-I (CLEAR-I). The experimental results at high heat pin input power were found to be in good agreement with the theoretical predictions.