A gas-cooled reactor employs which specific substances for its moderator and coolant____________________?
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Answer: A. graphite, C02
Explanation
Gas-cooled nuclear reactors utilize solid graphite blocks as their primary neutron moderator. Carbon dioxide gas is circulated through the core to transfer thermal energy away efficiently. This combination allows high operating temperatures and good thermodynamic power conversion efficiencies. Neutron moderators slow down fast fission neutrons to thermal speeds sustaining nuclear chain reactions. Reactor coolants transport thermal energy from the nuclear core to steam generators for power production. Gas coolants remain chemically stable and do not phase-change under high reactor core temperatures.
Advanced gas-cooled reactors form a major component of historic nuclear power generation fleets. High-temperature gas-cooled reactors are studied for industrial process heat and hydrogen production. Graphite moderation provides good neutron economy within gas-cooled reactor core designs. Heavy water is typically used as a moderator in pressurized heavy water reactor designs. Air is rarely used as a modern power reactor coolant due to activation and corrosion issues. Combinations like lead and hydrogen do not correspond to standard gas-cooled reactor technology.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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