A nuclear reactor is an apparatus in which nuclear
fission is takes place,in the form of a controlled self
sustaining chain reaction
Which burns fuels like U^235,U^233 or pu^239 and in
turns produces many useful products like
HEAT,NEUTRONS & RADIOSOTOPS
DESCRIPTION OF REACTOR
1.Gas Cooled Reactor
2.Water Cooled Reactor
Pressurised Water Reactor
Boiling Water Reactor
1.Pressurised Water Reactor
A Pressurised Water Reactor ,its Simplest form of water
Reactor. is a light water cooled & Moderated Thermal
reactor having an unusual core Design
The boiling water reactor (BWR) is a type of light water
nuclear reactor used for the generation of electrical
power. It is the second most common type of electricity-
generating nuclear reactor after the pressurized water
reactor (PWR), also a type of light water nuclear reactor.
The main difference between a BWR and PWR is that in a
BWR, the reactor core heats water, which turns to steam
and then drives a steam turbine. In a PWR, the reactor
core heats water, which does not boil. This hot water
then exchanges heat with a lower pressure water system,
which turns to steam and drives the turbine. The BWR
was developed by the Idaho National Laboratory and
General Electric in the mid-1950s.
Working Of BWR-
This is also simplest form of nuclear reactor, Heat is produced by
nuclear fission in the reactor core, and this causes the cooling water
to boil, producing steam. The steam is directly used to drive a turbine,
after which it is cooled in a condenser and converted back to liquid
water. This water is then returned to the reactor core, completing the
loop. In the Boiling water reactor the feed water acts both as coolant
& a moderator.
Advantages & Disadvantages Of BWR-
1.Heat exchanger circuit is eliminated & consequently there is gain in thermal efficiency &
2.There is use of a lower pressure vessel for the reactor as compare to PWR which further
3.The metal temperature remains low for given output condition.
4.The cycle for BWR is more efficient than PWR for given pressure.
5. Operates at a lower nuclear fuel temperature.
1.Possibility of radioactive contamination in the turbine mechanism,should there be any fa
2.More elaborate safety precautions needed Which are costly
3.Boiling limits power density:onil 3 to5% by mass can be converted to steam per pass thro