blading efficiency
nozzle efficiency
stage efficiency
mechanical efficiency
✅ The correct answer is option C.
Steam Nozzles and Turbines MCQs
42. The impulse turbine rotor efficiency will have a maximum value of 0.5 cos2 α, where α is the nozzle exit flow angle, if the
blades are equiangular
blade velocity coefficient is unity
blades are equiangular and frictionless
blade solidity is 0.65
✅ The correct answer is option C.
43. In impulse turbines, when friction is neglected, the relative velocity of steam at outlet tip of the blade is __________ the relative velocity of steam at inlet tip of the blade.
equal to
less than
greater than
✅ The correct answer is option A.
44. A steam nozzle converts
heat energy of steam into kinetic energy
kinetic energy into heat energy of steam
heat energy of steam into potential energy
potential energy into
✅ The correct answer is option A.
45. The effect of supersaturation is that the
mass of the steam discharged increases
entropy and specific volume of the steam increases
exit velocity of steam reduces
all of these
✅ The correct answer is option D.
46. During flow through a nozzle, no heat is supplied or rejected by the steam.
Agree
Disagree
✅ The correct answer is option A.
47. A steam turbine, in which a part of the steam after partial expansion, is used for process heating and the remaining steam is further expanded for power generation, is known as
back pressure turbine
pass out turbine
low pressure turbine
impulse turbine
✅ The correct answer is option B.
48. When the inlet pressure of steam is equal to the exit pressure, then
there is a pressure drop in the nozzle
fluid flows through the nozzle
pressure drops and fluid flows through the nozzle
there is no pressure d
✅ The correct answer is option D.
49. In a reaction turbine
the steam is allowed to expand in the nozzle, where it gives a high velocity before it enters the moving blades
the expansion of steam takes place partly in the fixed blades and partly in the moving blades
the steam is expanded from a high pressure to a condenser pressure in one or more nozzles
the pressure and tempe
✅ The correct answer is option B.
50. The velocity of whirl at outlet for an axial discharge turbine is
minimum
maximum
zero
✅ The correct answer is option C.