池式低温供热堆用自然循环阀门的结构设计与计算

Structural Designand Calculation of Natural Circulation ValveUsed for Pool-typed Low Temperature Heating Reactor

自然循环阀门是池式低温供热堆余热排出系统的关键设备。自然循环阀门被设置于反应堆堆芯容器侧壁,可以联通容器内、外部的流体,其自然循环功能通过水力关闭、非能动开启来实现。当反应堆一回路主泵运转后,自然循环阀门在正常工况支路射流的作用下保持关闭;在反应堆停堆后,自然循环阀门内外表面压差不断减小,阀门在重力作用下自动开启,容器内、外部流体联通,流体依靠温差建立自然循环,实现堆芯余热的非能动排出,对保证反应堆的安全性能具有重要意义。通过结构设计和力矩平衡计算,能够最终设计出满足功能要求的自然循环阀门。

Naturalcirculation valve is a key equipment of theresidual heat removal system of pool-typed low temperature heating reactor.The natural circulation valve is placed on the side wall of the reactor core vessel which can connect the fluid inside and outside the vessel together.Its natural circulation function is achieved by hydraulic closing and passive opening.When the main pump of the primary loop is running,the natural circulation valve remains closed under the normal working condition by branch jetting.After the reactor is shut down,the pressure difference between the inner and outer surfaces of the natural circulation valve is continuously reduced,and the valve is automatically opened because of itsgravity.When the fluid inside and outside the vessel is connected,a nature circulation will be established because of the temperature difference and the passive removal of the residual heat of the reactor core is achieved.This is important for ensuring the safe operation of the reactor.A nature circulation valve that meets the functional requirements can be finally designed by structure design and torque balance calculation.