含钆量对乏燃料组件衰变热的影响

Effect of gadolinium content on decay heat of spent fuel assemblies

压水堆核电厂乏燃料水池中内的乏燃料组件持续释放衰变热,由冷却系统对其持续冷却以控制乏燃料水池水温低于技术规范限值50℃。因此衰变热的计算对冷却系统的设计至关重要。文中以CPR1000机组的乏燃料组件为研究对象,采用ORIGEN/S程序,开展乏燃料组件燃耗计算和放射性核素衰变计算,并分析了含钆量对乏燃料水池衰变热的影响规律。计算结果表明:乏燃料组件含钆量越高,其衰变热越大;为了确保乏池冷却能力的设计的保守性和安全性,需要考虑含钆棒对燃料组件衰变热的影响。

The spent fuel assembly in the spent fuel pool of a PWR nuclear power plant continuously emits decay heat,which is continuously cooled by the cooling system to control the water temperature in the spent fuel pool below 50°C.So the calculation of decay heat is very important to the design of cooling system.In this paper,the spent fuel assembly of CPR1000 unit is studied,the burnup calculation and radionuclide decay calculation of spent fuel assembly are carried out by using ORIGEN/S program,the influence of Gadolinium content on the decay heat of spent fuel pool is analyzed.The results show that:the higher the Gadolinium content is,the greater the decay heat is;In order to ensure the conservation and safety of the design of spent fuel pool cooling capacity,it is necessary to consider the influence of gadolinium rod on the decay heat of fuel assembly.