Water entrained by circulating air in cooling towers is termed as________________?

Related Mcqs:

1. Water entrained by circulating air in cooling towers is termed as____________________?

   A. Drift
   B. Blow down
   C. Vapor load
   D. None of these

2. The reason for preferring packed towers over plate towers in distillation practice is that the packed tower operation gives___________________?

   A. Low pressure drop and high hold up
   B. High pressure drop and low hold up
   C. Low pressure drop and low hold up
   D. High pressure drop and high hold up

3. Plate towers are preferred to packed towers, when large temperature changes are involved, because of the reason that the____________________?

   A. Packing may be crushed due to thermal expansion/contraction of the components of the
   equipments
   B. Pressure drop in the equipment will be very high
   C. Viscosity variation of the fluids may cause channelling/flooding
   D. None of these

4. At equilibrium the concentration of water in vapour phase (C*) in kg/m3 of air space and the amount of water (m) adsorbed per kg of dry silica gel are related by, C* = 0.0667m. To maintain dry conditions in a room of air space 100m3 containing 2.2 kg of water vapour initially, 10 kg of dry silica gel is kept in the room. The fraction of initial water remaining in the air space after a long time (during which the temperature is maintained constant) is_________________?

   A. 0.0
   B. 0.2
   C. 0.4
   D. 1.0

5. An air-water vapour mixture has a dry bulb temperature of 60°C and a dew point temperature of 40°C. The total pressure is 101.3 kPa and the vapour pressure of water at 40°C and 60°C are 7.30 kPa and 19.91 kPa respectively. The humidity of air sample expressed as kg of water vapour/kg of dry air is__________________?

   A. 0.048
   B. 0.079
   C. 0.122
   D. 0.152

6. In case of cooling towers, the ratio of the rates of heat and mass transfer is indicated by the ______________ number ?

   A. Lewis
   B. Grashoff
   C. Sherwood
   D. None of these

7. Pick out the wrong statement pertaining to the cooling towers ?

   A. In case of induced draft cooling tower, the fan is placed at the top of the tower
   B. Effectiveness of forced draft cooling tower is reduced by the recirculation of the humid and
   hot discharged air
   C. A natural draft cooling tower is recommended to be used, when the air humidity is low and air
   temperature is also low
   D. Effectiveness of a mechanical draft cooling tower is reduced with increase in air wet-bulb
   temperature

8. Pick out the wrong statement pertaining to the cooling towers ?

   A. In case of induced draft cooling tower, the fan is placed at the top of the tower
   B. Effectiveness of forced draft cooling tower is reduced by the recirculation of the humid and
   hot discharged air
   C. A natural draft cooling tower is recommended to be used, when the air humidity is low and air
   temperature is also low
   D. Effectiveness of a mechanical draft cooling tower is reduced with increase in air wet-bulb
   temperature

9. The cooling effect in a cooling tower can be speeded up by _______________________?

   A. Increasing the air velocity and area of exposed wet surface
   B. Reducing the barometric pressure
   C. Reducing the humidity of the air
   D. All A., B. and C.

10. The cooling effect in a cooling tower cannot be increased by_____________________?

    A. Increasing the air velocity over the wet surfaces
    B. Reducing the humidity of entering air
    C. Lowering the barometric pressure
    D. None of these