Reactor Theory (Nuclear Parameters)
Changes in the physical properties of the materials in the reactor will result in
changes in the reactivity. Reactivity coefficients are useful in quantifying the
reactivity change that will occur due to the change in a physical property such as
the temperature of the moderator or fuel.
EXPLAIN the conditions of over moderation and under
EXPLAIN why many reactors are designed to be operated in
an under moderated condition.
STATE the effect that a change in moderator temperature will
have on the moderator to fuel ratio.
DEFINE the temperature coefficient of reactivity.
EXPLAIN why a negative temperature coefficient of reactivity
EXPLAIN why the fuel temperature coefficient is more
effective than the moderator temperature coefficient in
terminating a rapid power rise.
EXPLAIN the concept of Doppler broadening of resonance
LIST two nuclides that are present in some types of reactor
fuel assemblies that have significant resonance absorption
DEFINE the pressure coefficient of reactivity.
EXPLAIN why the pressure coefficient of reactivity is usually
negligible in a reactor cooled and moderated by a subcooled
DEFINE the void coefficient of reactivity.
IDENTIFY the moderator conditions under which the void
coefficient of reactivity becomes significant.