Effects of process-generated hydrogen on RPV walls

7.2. Pressure during normal operating conditions

(a) Initial concentration profile equal to steady state hot in-service condition.

(b) Time dependent concentration profile in the RPV wall during a cold shutdown.

(c) Zoom on time dependent concentra- tion profile close to the steel-water inter- face.

(d) Zoom on the time dependent concen- tration profile at the lining-base material interface in the RPV wall.

Figure 7.3: Concentration profile in the RPV wall as a result of the typical cooling path for the reactor coolant of a pressurized water reactor during a cold shutdown considering only corrosion generated hydrogen with a 10% absorption coefficient and a hydrogen generation rate of 50 mol H/yr.The lines show the concentration profile for different moments after the start of cooling. The interval between the lines corresponds to 1 h. The graphs show the concentration profiles up to 50 hours after the start of the cold shutdown. The initial concentration profile, shown in a), corresponds to the steady state profile for hot in-service condition.

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