Deck 7: Understanding Fluid Mechanics and Turbines

Question 1

Head loss in nozzles occurs due to __________

A)pipes head loss
B)pressure loss
C)friction loss
D)none of the mentioned

Answer 1

pipes head loss

Question 2

At vena contracta the velocity is _________ and pressure is ___________

A)lowest, highest
B)highest, highest
C)highest, lowest
D)none of the mentioned

Answer 2

highest, lowest

Question 3

When flow converts from supersonic to subsonic then __________ is produced.

A)shock wave
B)pressure drop
C)shock wave & pressure drop
D)none of the mentioned

Answer 3

shock wave

Question 4

Shock wave causes instantaneous _________ to the subsonic speed.

A)increase
B)decrease
C)remains constant
D)none of the mentioned

Question 5

Mixture of steam and liquid water is called as _________

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

Question 6

Supersaturated steam is also called as _________

A)saturated steam
B)single phase mix
C)two phase mix
D)none of the mentioned

Question 7

If heat is added to the wet steam temperature _________

A)raises immediately
B)decreases immediately
C)raises after sometime
D)none of the mentioned

Question 8

After steam bubbles break the water surface, they carry water droplets this is called as ________

A)entrainment
B)capillarity
C)reverse capillarity
D)none of the mentioned

Question 9

Entrainment happens at __________

A)liquid surface having contact with atmosphere
B)outlet of the boiler
C)inlet of the boiler
D)none of the mentioned

Question 10

Resistance of water dominating the steam is called as _______

A)hydraulic water hammer
B)erosion
C)contamination
D)none of the mentioned

Question 11

When steam is transported dryness fraction _________

A)increases
B)decreases
C)remains constant
D)none of the mentioned

Question 12

Coefficient of discharge is the __________ of Actual discharge to the theoretical discharge.

A)ratio
B)product
C)sum
D)none

Question 13

Coefficient of discharge is used to measure ___________

A)none of the mentioned
B)pressure exerted by the nozzle on the fluid
C)flow rate allowed by the nozzle
D)resistance offered by the nozzle

Question 14

Unit of flow resistance is _________

A)n/m²
B)m²/n
C)kn/kg
D)no unit

Question 15

Coefficient of discharge is the ____________

A)product of coefficient of velocity and coefficient of contraction
B)arithmetic sum of coefficient of velocity and coefficient of contraction
C)ratio of coefficient of velocity and coefficient of contraction
D)none of the mentioned

Question 16

Coefficient of discharge is _____________

A)directly proportional to coefficient of discharge
B)inversely proportional to square of the coefficient of discharge
C)inversely proportional to coefficient of discharge
D)directly proportional to square of coefficient of discharge

Question 17

For sharp edge orifice, coefficient of discharge lies between ___________

A)0.61 - 0.64
B)0.87 - 0.89
C)0.50 - 0.61
D)none of the mentioned

Question 18

In the equation Cd=1/K(0.5) what does K mean ?

A)pressure drop inside the nozzle
B)mass flow rate
C)flow resistance
D)none of the mentioned

Question 19

A turbine having alternate blades and nozzles is called as _______________

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

Question 20

Multi stage arrangement of turbines is called as __________

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

Question 21

Compounding __________ efficiency at low speed.

A)decrease
B)increase
C)maximizes
D)none of the mentioned

Question 22

In velocity compounded turbines flow passage is from ____________

A)moving blades to fixed nozzles
B)fixed nozzles to moving blades
C)fixed blades to moving nozzles
D)none of the mentioned

Question 23

A velocity compounded impulse turbine is also called as __________

A)curtis wheel
B)pressure compounded
C)curtis wheel & pressure compounded
D)none of the mentioned

Question 24

Reaction turbine is also called as _________

A)impulse turbine
B)curtis wheel
C)parsons turbine
D)none of the mentioned

Question 25

Compounding is used for _________ power applications.

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