SYSTEM FOR GIVING NATURAL CIRCULATING BOILING WATER REACTOR WITH LOAD FOLLOWING/ SPECTRAL SHIFT FACULTY

摘要

PURPOSE: To impart a load-flowing capacity while enhancing the spectrum shifting capacity by arranging first and second spargers connected in the pressure container of a nuclear reactor by pipings equipped with valves at different height positions. CONSTITUTION: The pressure container vessel of a nuclear reactor (RPV) 10 takes in water from its inlet 12 while discharges steam from its outlet 14. A sparger 16 is connected to the inlet 12 and a second sparger 18 is connected to the sparger 16 by piping 20 equipped with a valve 22. The flow characteristic in the RPV 10 is changed by controlling the valve 22 to divide the flow of water between the spargers 16, 18. By quenching the water within the RPV 10 at different height places, a drive waterhead is corrected to exert effect on an output level. The water in the RPV 10 is subcooled within a falling region 24 to downwardly flow through the gap between the RPW 10 and a shroud 26 within an annular region 28. The water flowing through the annular region 28 flows to a lower high pressure chamber region 30 thereafter.