Energy Engineering Exam 2 from Summary Sheet
Mass of parts vs. mass of an atom sum of parts vs actual mass is called the mass defect
What is the most stable atom? Iron. Larger nuclei have large total binding energy
•Most widely used reactor in the West and now worldwide.
•Water never boils in the core (which is pressurized - typically 150-200 atm
Pressurized water reactor •Heat exchanged in a second lower-pressure loop to generate turbine ste
•Minimizes equipment exposure to ionizing radiation and radioactive waste
production.
•Water boils directly in the core.
•Steam passes directly to turbine.
•After turbine, steam recondenses and returns to reactor.
Boiler Water Reactor (BWR)
•Large variations in heat transfer coefficients on the fuel rods.
•Turbine exposed to radioactive products from fluid, complicating mainten
and decommissioning.
, Energy Engineering Exam 2 from Summary Sheet
•Heavy water (deuterium- or tritium-based water) passes through pressuriz
fuel tubes surrounded by a non-pressurized heavy water bath.
•Operates on natural uranium
•Avoids pressurized reactor vessel (major expense).
Heavy Water Reactor
•Steam generated in second loop.
•Basis of the CANDU (Canadian) reactor designs.
•Variant is the heavy-water-moderated, light-water-cooled reactor (HWLW
that uses light water in the fuel tubes and no heat exchanger.
•Gas (He or CO2) used as coolant.
•Graphite typically used as moderator.
•Graphite (which remains solid) and gas need not be pressurized, eliminati
expensive pressure vessel.
Gas-cooled Reactor (GCR, HTGR) •Gas exchanges heat with steam in secondary loop.
•In a gas-cooled reactor (GCR), gas passes through holes in graphite
moderator.
•In a high-temperature gas-cooled reactor (HTGR), fuel channels and gas
channels are drilled in graphite core.
, Energy Engineering Exam 2 from Summary Sheet
•Fast-neutron-based reactor scheme.
•No moderator (no light elements).
•Na or K-Na molten metal used as coolant.
Liquid Metal Fast Breeder Reactor •No pressurization, very high heat transfer coefficients.
(LMFBR) •Na becomes radioactive and Na and K react violently with water.
•Second Na heat exchanger isolates Na/K coolant in core from turbine ste
•New fuel to consumed fuel ratio raises from 0.6-0.8 in typical reactors to o
if designed as a breeder reactor.
•Soviet-designed reactor, called RBMK (reactory bolshoi moshchnosti kan
- high-pored pressure-tube reactor).
•Fuel in pressurized fuel channels in graphite block.
Light-water-cooled, graphite moderated
•Steam passes directly to turbine.
reactor (LGR)
•Fuel can be exchanged without reactor shutdown.
•Can use minimally enriched fuel.
•All systems since Chernobyl use higher (2.4%) uranium enrichment.
•Six designs - three each of thermal and fast reactors
Gen 4 Reactors •Most will not be deployed until 2030 under current plans (one exception
Next Generation Nuclear Plant, or NGNP - targeted for 2021).
Pressurizer maintains ___________ in PWR, constant water pressure
not needed in BWR
Mass of parts vs. mass of an atom sum of parts vs actual mass is called the mass defect
What is the most stable atom? Iron. Larger nuclei have large total binding energy
•Most widely used reactor in the West and now worldwide.
•Water never boils in the core (which is pressurized - typically 150-200 atm
Pressurized water reactor •Heat exchanged in a second lower-pressure loop to generate turbine ste
•Minimizes equipment exposure to ionizing radiation and radioactive waste
production.
•Water boils directly in the core.
•Steam passes directly to turbine.
•After turbine, steam recondenses and returns to reactor.
Boiler Water Reactor (BWR)
•Large variations in heat transfer coefficients on the fuel rods.
•Turbine exposed to radioactive products from fluid, complicating mainten
and decommissioning.
, Energy Engineering Exam 2 from Summary Sheet
•Heavy water (deuterium- or tritium-based water) passes through pressuriz
fuel tubes surrounded by a non-pressurized heavy water bath.
•Operates on natural uranium
•Avoids pressurized reactor vessel (major expense).
Heavy Water Reactor
•Steam generated in second loop.
•Basis of the CANDU (Canadian) reactor designs.
•Variant is the heavy-water-moderated, light-water-cooled reactor (HWLW
that uses light water in the fuel tubes and no heat exchanger.
•Gas (He or CO2) used as coolant.
•Graphite typically used as moderator.
•Graphite (which remains solid) and gas need not be pressurized, eliminati
expensive pressure vessel.
Gas-cooled Reactor (GCR, HTGR) •Gas exchanges heat with steam in secondary loop.
•In a gas-cooled reactor (GCR), gas passes through holes in graphite
moderator.
•In a high-temperature gas-cooled reactor (HTGR), fuel channels and gas
channels are drilled in graphite core.
, Energy Engineering Exam 2 from Summary Sheet
•Fast-neutron-based reactor scheme.
•No moderator (no light elements).
•Na or K-Na molten metal used as coolant.
Liquid Metal Fast Breeder Reactor •No pressurization, very high heat transfer coefficients.
(LMFBR) •Na becomes radioactive and Na and K react violently with water.
•Second Na heat exchanger isolates Na/K coolant in core from turbine ste
•New fuel to consumed fuel ratio raises from 0.6-0.8 in typical reactors to o
if designed as a breeder reactor.
•Soviet-designed reactor, called RBMK (reactory bolshoi moshchnosti kan
- high-pored pressure-tube reactor).
•Fuel in pressurized fuel channels in graphite block.
Light-water-cooled, graphite moderated
•Steam passes directly to turbine.
reactor (LGR)
•Fuel can be exchanged without reactor shutdown.
•Can use minimally enriched fuel.
•All systems since Chernobyl use higher (2.4%) uranium enrichment.
•Six designs - three each of thermal and fast reactors
Gen 4 Reactors •Most will not be deployed until 2030 under current plans (one exception
Next Generation Nuclear Plant, or NGNP - targeted for 2021).
Pressurizer maintains ___________ in PWR, constant water pressure
not needed in BWR
