PASSIVE TRIGGERED SAFETY DEVICE FOR NUCLEAR REACTOR WITH DAMPER

The present invention relates to a passive triggered safety device for a nuclear reactor, the device comprising an assembly comprising: a sheath (200) and a mobile unit (100) and at least comprises a neutron absorbing section. The mobile unit (100) comprises a first supporting section (110), and the sheath (200) comprises a second supporting section (210). When the first supporting section and the second supporting section (110, 210) are arranged oppositely and the flow quantity Qf of a coolant flowing through the sheath (200) longitudinally is greater than a triggering flow quantity Q trigger, force applied to the mobile unit (100) by the coolant is great enough to support the mobile unit (100) in the sheath (200) and maintain a state under the condition of the configuration of the supporting force of the mobile unit (100). The safety device is characterized in that the first supporting section (110) and the second supporting section (210) form a component (112, 211) which defines (at least a part of) a visc