Q.1

The turbine blades are

  • straight
  • circular
  • curved
Q.2

The efficiency of steam turbines may be improved by

  • reheating of steam
  • regenerative feed heating
  • binary vapour plant
  • any one of these
Q.3

A binary vapour plant consists of

  • steam turbine
  • steam condenser
  • mercury boiler
  • all of these
Q.4

The reheat factor is the ratio of the

  • cumulative heat drop to the isentropic heat drop
  • isentropic heat drop to the heat supplied
  • total useful heat drop to the total isentropic heat drop
  • none of the above
Q.5

The supersaturated flow of steam through a nozzle as compared to a stable flow, the available heat drop

  • remains the same
  • increases
  • decreases
  • is unpredictable
Q.6

The value of the reheat factor varies from

  • 1.02 to 1.06
  • 1.08 to 1.l0
  • 1.2 to 1.6
  • 1.6 to 2
Q.7

The blade velocity coefficient is ratio of relative velocity of steam at outlet tip of the blade to the relative velocity of steam at inlet tip of the blade.

  • True
  • False
Q.8

The critical pressure ratio for initially wet steam is

  • 0.546
  • 0.577
  • 0.582
  • 0.601
Q.9

In a reaction turbine, when steam flows through the fixed blades,

  • pressure increases while velocity decreases
  • pressure decreases while velocity increases
  • pressure and velocity both decreases
  • pressure and velocity both increases
Q.10

In a De-Laval nozzle expanding superheated steam frombar to 0.1 bar, the pressure at the minimum cross-section (i. e. pressure at throat, p2) will be

  • 3.3 bar
  • 5.46 bar
  • 8.2 bar
  • 9.9 bar
Q.11

The turbine blades do not change the direction of steam issuing from the nozzle.

  • True
  • False
Q.12

The steam leaves the nozzle at a

  • high pressure and a low velocity
  • high pressure and a high velocity
  • low pressure and a low velocity
  • low pressure and a high velocity
Q.13

The steam enters the nozzle at a

  • high pressure and a low velocity
  • high pressure and a high velocity
  • low pressure and a low velocity
  • low pressure and a high velocity
Q.14

Multi-stage steam turbines are of the

  • velocity compounded type
  • reaction type
  • pressure compounded type
  • all of these
Q.15

Thermal equilibrium means that the flow of steam is

  • isothermal
  • isentropic
  • hyperbolic
  • polytropic
Q.16

A nozzle is said to be a convergent nozzle

  • when the cross-section of the nozzle increases continuously from entrance to exit
  • when the cross-section of the nozzle decreases continuously from entrance to exit
  • when the cross-section of the nozzle first decreases from entrance to throat and then increases from its throat to exit
  • none of the above
Q.17

A turbine is said to have an axial discharge when the steam leaves the blade tip at __________ to the direction of the blade motion.

  • 60°
  • 90°
  • 180°
  • 270°
Q.18

The flow through a nozzle is regarded as

  • constant volume flow
  • constant pressure flow
  • isothermal flow
  • isentropic flow
Q.19

The ratio of total useful heat drop to the total isentropic heat drop, is called

  • stage efficiency
  • internal efficiency
  • Rankine efficiency
  • none of these
Q.20

The pressure at which the steam leaves the nozzle is known as back pressure.

  • Correct
  • Incorrect
Q.21

In areaction turbine stage, tangential component of absolute velocity at rotor inlet ism/s and the blade velocity ism/s. The power output in kW of steam will be

  • 260 kW
  • 282 kW
  • 296 kW
  • 302 kW
Q.22

In a Parson's turbine stage, blade velocity ism/s at the mean radius and rotor blade exit angle is 30°. For minimum kinetic energy of the steam leaving the stage, the steam velocity at the exit of the rotor will be

  • 160/3 m/s
  • 320/3 m/s
  • 640/3 m/s
  • 640 m/s
0 h : 0 m : 1 s