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INPUT   DATA

♥ EXAMPLE Of Input/Output

Title

Nuclear fuel	U-235 Pu-239 U-238
Energy liberated per atom		MeV
Reactor power output		MW
Reactor efficiency		%

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OUTPUT   VARIABLES   &   GRAPHS

Variables	Values	Units
♦  Atoms consumed per day
♦  Mass consumed per day		kg

Fission Chain Reaction

Nuclear fission is a process in which the nucleus of an atom (having a large nucleus) liberates energy as it splits into two or three medium-sized nuclei. If the number of neutrons remains constant or increases in time, the process can lead the to a self-perpetuating chain-reaction. Nuclear fission is used to produce energy for nuclear power plant and to drive explosion of nuclear weapons. Chemical isotopes that can sustain a fission chain reactions are called nuclear fuels. The most commonly used ones are ²³⁵U (the isotope of uranium with an atomic mass of 235) and ²³⁹Pu (a plutonium isotope).

For a nuclear reactor generating power, the fuel consumption can be derived from the following relations:

Number of atoms consumed = [W/e.f]

Mass consumed = [W/(e.f.N_A)]

where
     W = reactor energy output
     f = efficiency of reactor
     e = energy released for each fuel atom underging fission, MeV (million electron volts)
     N_A = Avogadro's Number = 6.022x10²⁶ atoms per kmol of substance

Tips

    ◊ Use link EXAMPLE Of Input/Output  to demo data entry expectations and results; you may edit & use it as starting point

BIBLIOGRAPHY

• Bueche FJ & Hecht E; College Physics, Schaum's Outlines Series; McGraw Hill, New York, 1997.
• Lowe TL & Rounce JF; Calculations For A-Level Physics; Nelson Thornes Ltd, Cheltenham, UK, 2002