EPRI - Reactor Theory (Engineering Systems Training)
– Qs And As
Fission ✔️Ans -A neutron interaction in which a nucleus absorbs a
neutron, splits into two new nuclei and releases a large amount of energy; the
resulting fission fragments emit neutrons and gamma rays and then undergo
radioactive decay
Turbines ✔️Ans -A device with rotating blades that are connected
to a shaft and turned by having a fluid do work on the blades; in a nuclear
power plant, steam turbines are rotated by expanding steam
Describe how a nuclear power plant generates electricity ✔️Ans -
Nuclear fission creates heat, which generate steams. The steam rotates the
turbines, which turn the generator to produce electricity.
Nucleus ✔️Ans -The center of an atom containing 99.9% of its
mass and comprised of neutrons and protons held together in a very small
volume by nuclear force
Moderator ✔️Ans -The medium used to slow down fast neutrons
Coolant ✔️Ans -The medium used to remove heat from the reactor
core; the coolant keeps the reactor from overheating
Light Water Reactors ✔️Ans -A nuclear reactor that uses H2O, or
"light water," as the moderator and coolant
Control Rods ✔️Ans -A rod made up of a substance that controls
the neutron population inside a reactor; control rods are used to control the
reactor power and also to provide a mechanism for rapid shutdown of the
reactor, if necessary
Reactor Core ✔️Ans -The part of a nuclear reactor where the heat
is generated; it includes the fuel, cladding, fuel assemblies, moderator/coolant
and control rods
, Pressurized Water Reactor ✔️Ans -A nuclear reactor system that
pressurizes the coolant water to a high enough pressure to prevent boiling in
the core; the heated water leaves the core and flows through a steam
generator where steam is produced and used to drive turbines
Boiling Water Reactor ✔️Ans -A nuclear reactor in which water is
allowed to boil directly inside the reactor, thus creating steam; the steam is
dried and used to drive turbines
Radiation ✔️Ans -Sub-atomic particles and energy emitted by
unstable isotopes to become stable
Heat Exchanger ✔️Ans -A device used to transfer heat from one
medium to another; in nuclear plants, steam generators and condensers are
examples of heat exchangers, the former transferring heat from the primary
coolant to the secondary coolant of a PWR and the latter transferring the heat
from steam to water from a cooling tower or pond
Pressurizer ✔️Ans -A component in the primary system of a PWR
that is used to maintain the design pressure of the primary coolant (water)
Primary Coolant ✔️Ans -The cooling water that flows through the
core of a PWR
Condenser ✔️Ans -A component of a power plant that condenses
the steam leaving the turbines, changing the steam to liquid water
Describe the design differences between the two types of reactor systems
typically used in the United States ✔️Ans -PWRs are indirect cycle
with a liquid primary loop that flows through the reactor and a liquid/vapor
secondary side where the steam used to turn the turbines is produced in
steam generators. None of the primary fluid reaches the turbine, therefore
shielding of the steam cycle is not required.
BWRs are direct cycle. They require shielding of the steam cycle (including the
turbine) against potential radiation hazards present in the water and steam.
Describe the design differences (Steam Production) between the two types of
reactor systems typically used in the United States ✔️Ans -PWRs
– Qs And As
Fission ✔️Ans -A neutron interaction in which a nucleus absorbs a
neutron, splits into two new nuclei and releases a large amount of energy; the
resulting fission fragments emit neutrons and gamma rays and then undergo
radioactive decay
Turbines ✔️Ans -A device with rotating blades that are connected
to a shaft and turned by having a fluid do work on the blades; in a nuclear
power plant, steam turbines are rotated by expanding steam
Describe how a nuclear power plant generates electricity ✔️Ans -
Nuclear fission creates heat, which generate steams. The steam rotates the
turbines, which turn the generator to produce electricity.
Nucleus ✔️Ans -The center of an atom containing 99.9% of its
mass and comprised of neutrons and protons held together in a very small
volume by nuclear force
Moderator ✔️Ans -The medium used to slow down fast neutrons
Coolant ✔️Ans -The medium used to remove heat from the reactor
core; the coolant keeps the reactor from overheating
Light Water Reactors ✔️Ans -A nuclear reactor that uses H2O, or
"light water," as the moderator and coolant
Control Rods ✔️Ans -A rod made up of a substance that controls
the neutron population inside a reactor; control rods are used to control the
reactor power and also to provide a mechanism for rapid shutdown of the
reactor, if necessary
Reactor Core ✔️Ans -The part of a nuclear reactor where the heat
is generated; it includes the fuel, cladding, fuel assemblies, moderator/coolant
and control rods
, Pressurized Water Reactor ✔️Ans -A nuclear reactor system that
pressurizes the coolant water to a high enough pressure to prevent boiling in
the core; the heated water leaves the core and flows through a steam
generator where steam is produced and used to drive turbines
Boiling Water Reactor ✔️Ans -A nuclear reactor in which water is
allowed to boil directly inside the reactor, thus creating steam; the steam is
dried and used to drive turbines
Radiation ✔️Ans -Sub-atomic particles and energy emitted by
unstable isotopes to become stable
Heat Exchanger ✔️Ans -A device used to transfer heat from one
medium to another; in nuclear plants, steam generators and condensers are
examples of heat exchangers, the former transferring heat from the primary
coolant to the secondary coolant of a PWR and the latter transferring the heat
from steam to water from a cooling tower or pond
Pressurizer ✔️Ans -A component in the primary system of a PWR
that is used to maintain the design pressure of the primary coolant (water)
Primary Coolant ✔️Ans -The cooling water that flows through the
core of a PWR
Condenser ✔️Ans -A component of a power plant that condenses
the steam leaving the turbines, changing the steam to liquid water
Describe the design differences between the two types of reactor systems
typically used in the United States ✔️Ans -PWRs are indirect cycle
with a liquid primary loop that flows through the reactor and a liquid/vapor
secondary side where the steam used to turn the turbines is produced in
steam generators. None of the primary fluid reaches the turbine, therefore
shielding of the steam cycle is not required.
BWRs are direct cycle. They require shielding of the steam cycle (including the
turbine) against potential radiation hazards present in the water and steam.
Describe the design differences (Steam Production) between the two types of
reactor systems typically used in the United States ✔️Ans -PWRs
