Chapter 13 Pump Head Calculations Flashcards
Which tank has the greatest pressure head?
A) Tank A – P1
B) Tank B - P2
B
What are the typical causes of pump cavitation?
1.Having the pump to low below the source
2.Suction Diameter too large for the pump
3.Insufficient Net Positive Suction Head energy on the suction side of the pump
4.Having the pump at too high of a distance above the fluid source
5.Having too small of a diameter of suction pipe
6.Having too long of a distance of suction pipe
A) 2, 3, 6
B) 1, 3, 4, 5
C) 3, 4, 5, 6
D) 1, 3, 4, 5
E) 3, 4, 5
C
In a closed system containing a liquid, no vapours will form as long as the liquid is exposed to
A) A temperature that is lower than the liquid vapour pressure
B) A pressure increase with a temperature decrease
C) A pressure increase with a temperature increase
D) A pressure that is greater than the vapour of the liquid at that liquids temperature
D
NPSH is;
A) Net Positive Suction Head
B) Negative Positive Suction Head
C) Net Pressure Suction Head
D) Net Positive System Head
A
At what point will vapour bubbles form in the pump suction and casing.
A) When the pump suction source tank level is higher than the discharge tank level
B) When the pressure at any point inside a centrifugal pump drops below the vapour pressure in the liquid
C) When the pressure at any point inside a centrifugal pump increases above the vapour pressure in the liquid
D) When the static suction head is greater than the total static head
B
Total static head for a pump when the pump suction is below the vessels is defined as;
A) Static Suction Head minus Total Static Head
B) Static Discharge Head minus Static Suction Head
C) Total Static Head plus Static Discharge Head
D) Total Static Head plus Static Suction Head
B
Pumps are designed to move liquids through a certain;
A) Pipe Friction Head
B) Equivalent Head
C) Maximum Head
D) Static Head
C
Total Dynamic Head on an operating pump with suction lift can be calculated by;
A) Total Head = dynamic suction lift – dynamic discharge head
B) Total Head = static suction head – suction friction head + suction velocity head
C) Total Head = dynamic suction lift + static suction head
D) Total Head = dynamic suction lift + dynamic discharge head
D
An open cylindrical tank 3 meters in diameter contains a liquid to a height of 8.5 meters. If the density of the liquid is 4.9 x 103 kg/m3, what is the pressure exerted by the liquid at the bottom of the tank?
A) 41.4 kPa
B) 408.6 kPa
C) 590.8 kPa
D) 706.6 Kpa
B
The equivalent water head for a fluid with a density of 0.917 kg/ m3
A) 8.99 kpa
B) 8.18 Kpa
C) 9.18 Kpa
D) 9.81 Kpa
A
If 9.81 Kpa is equal to 1 m of head, then 1 kpa equals how many meters?
A) 10.2 m
B) 1/9.81 m
C) 1.02 m
D) 0.102/9.81 m
B
Using the steam tables calculate the density of water at temperature of 90 C.
A) 965.3
B) 790.7
C) 970.3
D) 709.1
A
