When a reactor utilizes a reflector, the fuel inventory required to achieve a self-sustaining chain reaction is________________?
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Answer: B. less
Explanation
Installing a reflector around a reactor core bounces leaking neutrons back into the active fuel region. Returning escaped neutrons increases the overall neutron economy, lowering the critical mass needed for a chain reaction. With fewer neutrons escaping, less fissile fuel inventory is required to sustain steady-state fission. Neutron reflectors are constructed from materials with high scattering cross-sections and low neutron absorption rates. Critical mass represents the minimum amount of fissile material needed to maintain a self-sustaining nuclear chain reaction. Core leakage reduction directly translates to significant economic savings in enriched nuclear fuel procurement.
Reactor designers use reflectors to reduce the physical size and overall weight of nuclear power systems. Spacecraft nuclear reactors utilize reflectors to minimize fuel mass and optimize payload efficiency during missions. Efficient reflector placement enhances reactor safety margins by improving core reactivity control and stability. Requiring more fuel contradicts the physical purpose of reflecting escaping neutrons back into the core. Stating the fuel inventory remains the same ignores the measurable reactivity savings provided by reflectors. Zero or negative fuel inventory values represent physical impossibilities in practical nuclear reactor engineering.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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