Effects of process-generated hydrogen on RPV walls

7.2. Pressure during normal operating conditions

Figure 7.1: Typical cooling path for the reactor coolant in a pressurized water reactor during a cold shutdown.

from the COMSOL Multiphysics materials database. For the bulk of the RPV wall, steel A508 Cl.3 from the material database is used, SS309 represents the RPV lining material. The initial temperature in the RPV wall is set to be 573.15 K, 300 ◦ C, homogeneously over the complete thickness of the RPV wall. For conservativeness the outer surface of the RPV wall is considered to be thermally insulated. This means all heat is dissipated through the reactor coolant. The inner wall is in equilibrium with the reactor coolant and, thus, has the exact same temperature as the reactor coolant. The temperature profile for the inner wall therefore follows the same path as shown in Figure 7.1. The initial and boundary conditions together with all the material properties used are shown in Table 7.1. The resulting temperature profile over the complete thickness of the RPV wall as a function of time is shown in Figure 7.2.

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