In RBMK reactors, what core feature distinguishes its design?

In RBMK reactors, what core feature distinguishes its design?

• A. The core uses heavy water as moderator
• B. The core is pressurized with steam
• C. The core is surrounded by channels (pipes) for coolant flow
• D. The core uses a spherical design

Answer: (C)

RBMK reactors are defined by their channel-type core: hundreds of vertical channels through which the coolant passes, all embedded in a large graphite moderator. Each fuel assembly sits in its own channel, and the light water coolant flows directly through these channels to remove heat. This arrangement—coolant flowing through channels in the core—is the feature that sets the RBMK design apart from other reactor types. In contrast, this design does not use heavy water as moderator, nor does it have the core pressurized with steam, and the core shape is not spherical. The channel-based pathway for coolant in the graphite matrix is the distinctive hallmark.

RBMK reactors are defined by their channel-type core: hundreds of vertical channels through which the coolant passes, all embedded in a large graphite moderator. Each fuel assembly sits in its own channel, and the light water coolant flows directly through these channels to remove heat. This arrangement—coolant flowing through channels in the core—is the feature that sets the RBMK design apart from other reactor types.

In contrast, this design does not use heavy water as moderator, nor does it have the core pressurized with steam, and the core shape is not spherical. The channel-based pathway for coolant in the graphite matrix is the distinctive hallmark.