PWR Loss-of-Coolant Accident LOCA

The important steel reactor pressure vessel analysis is to check them against loss-of-coolant accident (LOCA), especially in PWR. A loss-of-coolant accident (LOCA) occurs as a result of a penetration to the main coolant boundary such that the primary circuit water is released through the break to the containment area, causing a rapid decrease in the pressure and temperature of the primary coolant Fig. 4.19. This will give an impact thermal shock load. The streamline break accident (SLBA) occurs as a result of a complete and partial rupture of a steam line inside the containment vessel. A rapid cool-down and depressurization of the primary circuit normally take place. In order to restore 

Hydrogen detonation has become an important issue after the Three-Mile-Island accident. The hydrogen burning occurred approximately 10 hours into the accident. The steam reacting with the Zircaloy cladding and the oxidation of the overheated steel vessel interiors created large quantities of hydrogen. This can also occur due to interaction of the molten core. In order to predict the wall pressures due to such detonations, non-linear gas dynamics equations for the entire volume of the containment vessel have to be solved. In the current analysis of the Sizewell B containment vessel, it is assumed that the wall pressure 

The safety of nuclear installations such as the pressure vessel and its piping systems requires strict measures. In the event of steel failure, the safety rules 

The jet impinging force against P T/P for failure conditions is given in Figs. 4.28 and 4.29 

Liner Cy = 390 MPa Strain rate = 0.1/s Pressures and shock front 

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