Multiple channel array reactors

All the structures from the boron steel plate and above are penetrated by a vertical fuelling standpipe which allows fuel and control rods to be inserted into, and removed from, the reactor. Each fuelling standpipe serves 12 fuel channds clustered around a central control rod channel as shown in Figure 3. Multiples of the array shown in Figure 3 can be interlocked to cover the whole core completely. 

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