The purpose of this study is to develop the core inlet orifice whose drag coefficient changes according to flow rate without drive parts. We improved on the conventional orifice by giving it a novel shape; the edge of the improved orifice is half-oval in shape. This improved orifice was tested under high-pressure and high-temperature (about 7.2 MPa and 570 K) simulated ABWR conditions. Test results showed that the drag coefficient of the orifice with the novel shape changed according to flow rate. It was found from these test results that drag coefficient was constant and high under ABWR natural circulation conditions and decreased by about 20% under ABWR rated power conditions. In addition, a task for the future was educed.
|ジャーナル||Journal of Nuclear Science and Technology|
|出版ステータス||Published - 2001 9月|
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