Heat Transfer Operations Mock Test 6

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Question 1 of 10

1. Boiling point of a solution is a colligative property.

True

False

Question 1 of 10

Question 2 of 10

2. What is the Evaporator Consumption if we evaporate 10kg of water from a feed of 50kg at a temperature of 25℃ to a final temperature of 100℃ in an hour?
Latent heat of vaporization of water = 2,260 kJ/kg
Specific heat capacity = 6 KJ/Kg K

22kg/hr

20kg/hr

21kg/hr

19kg/hr

Question 2 of 10

Question 3 of 10

3. The boiling that takes place in forced convection boiling is popularly known as surface boiling.

True

False

Question 3 of 10

Question 4 of 10

4. The fluids in falling tube evaporator usually form a film inside the tubes but there are applications when the fluid forms a film outside the tube and falls subsequently.

False

True

Question 4 of 10

Question 5 of 10

5. In the given formula for overall heat transfer coefficient in Rising film evaporators, What is the term h_OD?
\(\frac{1}{U}=\frac{1}{ho}+\frac{1}{h_{OD}}+(\frac{Do}{Di})(\frac{1}{h_{ID}})+ (\frac{Do}{Di})(\frac{1}{hi})\)

Outside film heat transfer coefficient

Inside dirt coefficient

Outside dirt coefficient

Inside film heat transfer coefficient

Question 5 of 10

Question 6 of 10

6. The boiling point of a solution is a colligative property because?

It depends on the heat capacity of the solution

It depends on the applied pressure on the solution

It depends on the concentration of solution

It depends on the temperature of solution

Question 6 of 10

Question 7 of 10

7. Which one of the following is not an assumption taken before applying enthalpy balance on the evaporator?

The superheat and sub-cooling conditions of the condensable steam is negligible

No fouling should occur on the evaporator surface

No solid should precipitate out from the concentrating solution

Flow of non-condensable gas is negligible

Question 7 of 10

Question 8 of 10

8. In order to maintain conservation of mass as this fluid fall proceeds in a falling film evaporator, the downward vapour velocity ___________

Oscillates

Remains Same

Increases

Decreases

Question 8 of 10

Question 9 of 10

9. Falling film evaporators have __________ product holdup.

Very high

Zero

Large

Low

Question 9 of 10

Question 10 of 10

10. What is the amount of heat that needs to be supplied in order to evaporate 10kg of water from a feed of 50kg at a temperature of 25℃ to a final temperature of 150℃?
Latent heat of vaporization of water = 2,260 kJ/kg
Specific heat capacity of solution = 4 KJ/Kg K

2272.6 MJ

56200 KJ

52600 KJ

47600 KJ

Question 10 of 10