ナトリウム冷却高速炉1次系ホットレグ配管の流力振動評価,5; LES解析結果に基づいたエルボ部の圧力変動発生メカニズムに関する考察

Evaluation for flow-induced vibration of a primary circuit hot-leg piping in a sodium-cooled fast reactor, 5; Study on mechanism of pressure fluctuation at elbow based on LES result

村上 貴裕*; 江口 譲*; 田中 正暁  ; 山野 秀将   

Murakami, Takahiro*; Eguchi, Yuzuru*; Tanaka, Masaaki; Yamano, Hidemasa

In a conceptual design of Japan Sodium-cooled Fast Reactor (JSFR), short-elbow pipings with large-diameter are adopted for cooling system, in which the coolant flow causes periodical pressure fluctuation at the short-elbow. However, the mechanism of the periodical pressure fluctuation has not been clarified yet. In this paper, unsteady three-dimensional analysis by a finite element large-eddy simulation (LES) code is carried out in order to explore the mechanism of the periodical pressure fluctuation in short-elbow pipings, based on visualizations of dynamic flow structure in the numerical results.