Deck 12: Steam Turbines and Power Cycles

Question 1

If the critical pressure ratio for steam is 0.546, then the steam is initially ____________

A)wet
B)dry saturated
C)superheated
D)none of the mentioned

Answer 1

superheated

Question 2

A stage, in reaction turbine, is represented by ____________

A)each row of blades
B)number of entries of steam
C)number of exits of steam
D)none of the mentioned

Answer 2

each row of blades

Question 3

Steam turbines may be classified according to ____________

A)number of stages
B)direction of steam flow
C)mode of steam action
D)all of the mentioned

Answer 3

all of the mentioned

Question 4

A steam nozzle converts ____________

A)heat energy of steam into kinetic energy
B)kinetic energy of steam into heat energy
C)potential energy into heat energy
D)none of the mentioned

Question 5

A steam turbine with no nozzle is?

A)reaction turbine
B)impulse turbine
C)reaction & impulse turbines
D)none of the mentioned

Question 6

_______ of electricity in United States is produced using steam turbine.

A)88%
B)50%
C)100%
D)77%

Question 7

When steam pressure ________ it becomes superficial fluid.

A)decreases
B)increases
C)steam can not become superficial fluid
D)none of the mentioned

Question 8

Steam turbines used in nuclear reactors use __________

A)superficial fluids
B)high pressure steam
C)specific heat
D)none of the mentioned

Question 9

Superficial steam power plants operate at _____ temperatures.

A)high
B)low
C)constant
D)none of the mentioned

Question 10

Energy efficiency of superficial steam is _________

A)low
B)high
C)same as other steams
D)none of the mentioned

Question 11

Superficial steam turbines can be operated at ________

A)medium speeds
B)low speeds
C)high speeds
D)none of the mentioned

Question 12

Superficial steam turbines releases _______ CO₂.

A)high
B)low
C)does not release
D)none of the mentioned

Question 13

Which statement about reaction turbine is false?

A)steam does not expand in nozzle
B)blades acts like nozzles
C)steam expands as flows over the rotor blades
D)steam continuously losses its heat as flows over the rotor blades

Question 14

Reaction turbines are characterized by ___________

A)relatively low rpm and steam expension over nozzle
B)relatively high rpm and steam expension over nozzle
C)relatively low rpm and steam expension over rotor blades
D)relatively high rpm and steam expansion over rotor blades

Question 15

In condensing turbine what is the back pressure of the turbine?

A)very high
B)above atmospheric pressure
C)equal to atmospheric pressure
D)below atmospheric pressure

Question 16

Having two separate units for process heat and power is?

A)useful
B)useless
C)pollution reducing
D)none of the mentioned

Question 17

Back pressure turbine is placed between ____________

A)turbine & pump
B)boiler & pump
C)turbine & heat exchanger
D)boiler & turbine

Question 18

Addition of an infinitesimal amount of heat at the highest temperature is because ___________

A)to initiate reheating
B)to initiate regeneration
C)to initiate superheating
D)none of the mentioned

Question 19

High moisture content is involved during expansion of steam because ___________

A)to ensure uniform heating
B)to ensure uniform cooling
C)to obtain a higher temperature of heat addition
D)to obtain a lower temperature of heat addition

Question 20

What is the relation of the mean temperature of heat addition and cycle efficiency?

A)both are inversely proportional
B)both are directly proportional
C)both are independent of each other
D)none of the mentioned

Question 21

Temperature of heat rejection in a condenser can be lowered by using?

A)lubricant
B)oil
C)refrigerant
D)diesel

Question 22

The use of which of the following becomes necessary during expansion of steam?

A)reheat
B)regeneration
C)refrigeration
D)superheat

Question 23

What is the specific heat of the ideal working fluid used in vapour power cycle?

A)should be constant
B)should be large
C)should be small
D)none of the mentioned

Question 24

What is the importance of the freezing point of the working fluid in the vapour power cycle?

A)freezing point of working fluid should be below the room temperature
B)freezing point of working fluid should be above the room temperature
C)freezing point of working fluid should be equal to the room temperature
D)does not have any importance

Question 25

The engines which are operating on gas power cycle are?

A)cyclic
B)non-cyclic
C)either cyclic or non-cyclic
D)none of the mentioned