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Energy Engineering Multiple Choice Questions on “Types of Nuclear Reactor & Nuclear Waste”.
1. PWR stands for ________
A. Power
B. Partially weathered rock
C. Pressurized water Reactor
D. Packaging waste regulations
Answer: C
clarification: PWR stands for pressurized water reactor. A PWR power plant consists of two loops in series. One is the coolant loop called primary loop and other is the water steam or working fluid loop. Pressurized water reactor falls under the category of light water reactor.
2. What does the top of the pressurizer in pressurized water reactor consists of at primary system pressure?
A. Steam
B. Air
C. Water
D. Fluids
View Answer
Answer: A
clarification: The pressurizer is a pressure vessel with a heater at the bottom and water spray at the top. The top of the pressurizer is filled with steam at primary system pressure. If the primary loop pressure drops, the heater is energized to increase the steam content in the pressurizer and thus increases the pressure of primary cooling system.
3. Select the incorrect statement which supports PWR.
A. Water is used as coolant
B. PWR is stable in operation
C. Uses natural fuel
D. PWR has positive power demand coefficient
View Answer
Answer: C
clarification: PWR uses enriched fuel making the reactor more compact in size. And due to high negative temperature coefficient, a PWR is stable. Water is used as the coolant. It does have positive power demand coefficient and responds greatly to more power demand.
4. Select the incorrect statement about PWR.
A. High primary circuit pressure requires a strong pressure vessel
B. Corrosion is less in PWR
C. During fuel charging in PWR, the reactor has to be shut down at least for a month
D. PWR results in uneven heating
View Answer
Answer: B
clarification: Presence of high temperature and high pressure water, the corrosion is severe. This means use of stainless steel adds to further costing. When γ- radiations pass through the pressure vessel it results in uneven heating which induces thermal stresses on vessels.
5. LWR stands for _________
A. Lower water reactor
B. Line water reactor
C. Liquefied water reactor
D. Light water reactor
Answer: D
clarification: The light water reactor is a type of thermal-neutron reactor that uses normal water, as opposed to heavy water, as both its coolant and neutron moderator – furthermore a solid fissile element is used as fuel. These are most common type of Thermal-neutron reactors.
6. In which reactor is the coolant in direct contact with the heat producing nuclear fuel?
A. Fast breeder reactor
B. Pressurized water reactor
C. Boiling water reactor
D. Heavy water reactor
Answer: C
clarification: In boiling water reactor, the coolant is in direct contact with the heat producing nuclear fuel and boils in the same compartment in which the fuel is located. The reactor pressure is maintained at 70bar. The coolant thus serves the triple function of coolant, moderato and working fluid.
7. How many types of Boiling water reactor cycles are there?
A. 2
B. 3
C. 4
D. 5
Answer: B
clarification: There are three different types of BWR cycles commonly used:
Single cycle internal circulation: This system uses internal recirculation system to generate power ranging from 50- 100 MW.
Single cycle forced circulation: This type uses a forced circulation system using a circulation system using a circulating pump. The heat in the reactor is used to generate steam.
Dual cycle forced circulation: this arrangement has two cycles, steam cycle and gas cycle.
8. Which country invented CANDU heavy water reactor?
A. Canada
B. Germany
C. Russia
D. Bolivia
View Answer
Answer: A
clarification: The CANDU is a Canadian pressurized heavy water reactor design used to generate electric power. Heavy water nuclear reactors and light water nuclear reactors differ in how they create and manage the complex physics of nuclear fission or atom-splitting which produces the energy and heat to create steam to drive generators.
9. In which of the Following reactor is heavy hydrogen isotope H-2 is used as moderator?
A. Boiling water reactor
B. Pressurized water reactor
C. Candu reactor
D. Thermal reactor
Answer: C
clarification: Heavy water composed of heavy hydrogen isotope H-2 is used as a moderator and coolant in some power and research reactors. These reactors use heavy water as a moderator and primary coolant and light water as secondary coolant.
10. CANDU stands for ____________
A. Canadian Natural Darmstadtium Uranium
B. Canadian Natural Deuterium Uranium
C. Canadian Natural Dubnium Uranium
D. Canadian Natural Dysprosium Uranium
Answer: B
clarification: The CANDU, for Canada Deuterium Uranium, is a Canadian pressurized heavy water reactor design used to generate electricity. The acronym refers to its deuterium oxide (heavy water) moderator and its use of (originally natural) Uranium fuel.
11. Which reactor consists of both fertile and fissile material?
A. Fast breeder reactor
B. Pressurize water reactor
C. Boiling Water reactor
D. Converter reactor
Answer: A
clarification: If the reactor produces more fissionable material than it consumes, it is fast breeder reactor. The breeder fuel consists of both fertile and fissile material. The number of neutrons released is sufficient to propagate the fission reaction and to produce more fissionable material by conversion of fertile isotopes to fissile isotopes.
12. What is acronym of LMFBR?
A. Liquid molecular fast boiling reactor
B. Liquid metal fast breeder reactor
C. Liquefied metal fast boiling reactor
D. Liquid metal fast boiling reactor
Answer: B
clarification: LMFBR stands for Liquid metal fast breeder reactor. The fuel consists of 80% by weight of UO2 by weight of PuO2 in small diameter stainless steel clad tubes operating at temperature of 670oC – 700oC.
13. GCFBR stands for ____________
A. Gas conditioned fast breeder reactor
B. Gas cooled fast breeder reactor
C. Gas conditioned fast boiling reactor
D. Gas cooled fast breeder reactor
Answer: B
clarification: The GCFBR stands for Gas cooled fast breeder reactor; it is cooled by helium gas at 85bar. Also helium doesn’t become radioactive under neutron bombardment AND hence secondary coolant is not needed.
14. Using Helium gas in GCFBR has many advantages.
A. True
B. False
View Answer
Answer: A
clarification: Using helium as coolant posses less severe metallurgical and safety problems. Heat transfer coefficient of helium is much superior than sodium with artificial roughening of fuel rod surfaces. Low doubling time as compared to sodium cooled reactors.
15. Which reactor uses orthometaerhenyl and paratherphenyl as coolant and moderator?
A. Liquid metal fast breeder reactor
B. Gas cooled fast breeder reactor
C. Organic substance cooled reactor
D. CANDU Heavy water reactor
Answer: C
clarification: Organic substance cooled reactor uses enriched uranium as fuel and a mixture of orthometaterhenyl and paratherphenyl as coolant and moderator, and boron control rods, generating 11.4 MW capacities with an overall efficiency of 25%.
16. Nuclear plant is located near the area where cooling water is available.
A. True
B. False
Answer: A
clarification: Some of the major factors to locate a nuclear station considered are, Availability of cooling water, transportation facilities, Distance from load centre, safety, radioactive waste, disposal facility and foundation requirement.