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Summary: Merits in the inherent safety characteristics and multiple applications, cause the pebble‐bed‐type nuclear reactors, including the High‐Temperature Gas‐cooled Reactors, Fluoride‐salt‐cooled High‐temperature Reactors and Water‐cooled Pebble‐bed Reactors, to gain more focus in recent years. Thermal‐hydraulic characteristics in the pebble bed reactor core are of great significance to the safety evaluation and design of such reactors. Experimental investigations on the thermal‐hydraulics of different fluids in the pebble‐bed‐type of nuclear reactor core have been reviewed in this paper. Main experimental methods to determine the flow regime transition, convective heat transfer coefficients, and effective thermal conductivity have been summarized, with the merits and disadvantages discussed. Discussions are given on the main factors that can influence the flow, convective heat transfer and effective thermal conductivity in the pebble bed. [ABSTRACT FROM AUTHOR]

Summary: In situ growing conductive polyaniline (PANi) has been regarded as a functional binder to enhance the performance of silicon based anodes in half cells, while few papers discussing the influence of Mn2+ from cathode on full cells. In this paper, the effects of Mn2+ on NSi@PANi electrodes in both half and full cells are investigated, and the mechanism for the fast capacity fade of LiMn2O4/NSi@PANi full cell is elucidated. Results reveal that the full cell will significant accelerate the capacity fade of NSi@PANi anode, and the extra consumption of active Li+ and electrolytes caused by the deposited Mn2+ on silicon anodes in lithium manganate (LMO)/NSi@PANi full cells is confirmed as the main reason of the capacity fade and lower coulombic efficiency for the excessive growth of solid electrolyte interphase. [ABSTRACT FROM AUTHOR]

Nonwater fluids have been widely adopted in the designs of several advanced nuclear reactors, especially the fourth-generation nuclear reactors and International Thermonuclear Experimental Reactor (ITER) blankets. Relap5 Mod3, initially developed for the water-cooled nuclear reactors, can continue to be applied to conduct the transient analysis of nonwater-cooled nuclear reactor systems as recommended. Thermodynamic and transport properties of fluoride salts, sodium, and lithium-lead eutectic are summarized and embedded into the Relap5 Mod3 code. Flow and heat transfer empirical correlations specific for low-Prandtl-number liquid metal and high-Prandtl-number fluoride salts are also added into the corresponding modules of the code. Through the benchmark problems including the protected loss of forced cooling of Mark1 pebble bed fluoride-salts-cooled high-temperature reactor and the Shutdown Heat Removal Test (SHRT) 17 of Experimental Breeder Reactor II, the modified Relap5 Mod3 has been verified and validated for the transient simulation of the fluoride-salt-cooled high-temperature reactors and sodium-cooled fast reactors. An ITER demo lithium-lead eutectic blanket, China Dual-Functional Lithium-Lead Test Blanket Module (DFLL-TBM), also proves safe under the protected loss of forced cooling accident through the analysis of the modified Relap5 Mod3. [ABSTRACT FROM AUTHOR]