A Study on thermal feasibility of 1356 MWe high conversion type innovative water reactor for flexible fuel cycle (FLWR)

1356MWe級革新的水冷却増殖炉熱水力特性評価

Liu, W.; 大貫 晃; 呉田 昌俊   ; 高瀬 和之; 秋本 肇

Liu, W.; Onuki, Akira; Kureta, Masatoshi; Takase, Kazuyuki; Akimoto, Hajime

原子力機構が開発した稠密バンドル用BT相関式をTRAC-BF1に組み込み、1350MWe級高転換炉心における熱水力特性を評価した。MCPRが1.3になるように必要な冷却材流量を算出した。また、強制循環並びに自然循環で水冷却増殖炉で想定された最も厳しい異常な過渡変化及び事故事象-「ポンプトリップによる流量低下事象」に対して、過渡解析を行い、沸騰遷移が発生しないことを確認した。

A new reactor concept of Innovative Water Reactor for Flexible Fuel Cycle (FLWR) is under development at Japan Atomic Energy Agency (JAEA). A design for high conversion type FLWR with 1350 MWe has been constructed, which has the conversion ratio of 1.04, a negative void reactivity coefficient, the high burnup of 65 GWd/t and the 15-month operational cycle length. This study investigates the thermal feasibility of the designed FLWR core using transient analysis code TRAC-BF1 which includes the critical power correlation and the pressure drop estimation method verified with experimental data. Core inlet coolant flow rate which ensures the thermal margin of MCPR = 1.3 was derived by the TRAC-BF1 code. Analysis to the postulated severest abnormal transient event-flow decrease event due to a failure of one recirculation pump, was performed using the core flow rate as the initial one. No boiling transition was confirmed to be occurred during the event.