CHAPTER 8 COOLING TOWER TEST
1. The measurement of how much water the air has absorbed at a given temperature.
a. relative humidity
b. standard humidity
c. wet bulb
d. approach to the tower
2. Devices used in a cooling tower to keep water from blowing out.
a. louvers
b. drift eliminators
c. columns
d. splash bars
3. _______________ is a term applied to the horizontal direction that air takes in
relationship to the downward flow of water in a cooling tower. _______________ is a
term applied to the vertical flow of air as it moves through a cooling tower in relationship
to the downward flow of water.
a. induced and forced
b. horizontal and counterflow
c. cross and vertical
d. cross and counterflow
4. The objective of water treatment is to reduce or minimize all of the following except:
a. Scale formation- suspended solids form deposits
b. Corrosion- electrochemical reactions with metal surfaces
c. Fouling- silt, debris, algae plug exchanger tubes
d. Wood decay- fungi
e. pH increase or decrease
f. water deionization
5. Heat that can be measured or sensed is referred to as:
a. latent heat of vaporization
b. latent heat of condensation
c. sensible heat
d. latent heat of fusion
6. The approach to tower is the:
a. Relative humidity minus the dry bulb
b. Wet-bulb minus the dry-bulb
c. temperature delta ∆ that exists between the relative humidity and the wet-bulb
temperature of the air leaving the tower.
d. temperature delta ∆ that exists between the water leaving the tower and the wet
bulb temperature of the air entering the tower.
7. Dry bulb temperature is the:
a. the air temperature as measured by a bulb thermometer covered by a water
saturated wick. Takes into account the relative humidity.
b. combination of dry and wet-bulb temperature
c. air temperature as measured by a dry-bulb thermometer
d. wet-bulb temperature minus the relative humidity
8. The wet bulb temperature is the:
a. the air temperature as measured by a bulb thermometer covered by a water
saturated wick. Takes into account the relative humidity.
b. combination of dry and wet-bulb temperature
c. air temperature as measured by a dry-bulb thermometer
d. wet-bulb temperature minus the relative humidity
9. Identify the following components:
9-1_______________ 9-2________________ 9-3______________
9-4_______________ 9-5________________ 9-6______________
9-7_______________ 9-8________________ 9-9______________
9-10______________
10. A cooling tower has a(n):
a. box shaped collection of multi-layered wooden slats and louvers that direct air
flow and breaks up water as it falls from the top of the tower or water distribution
header.
b. internal design of the tower ensures good air and water contact.
c. chimney design used to move air flow by buoyancy forces.
d. a & b
11. A cooling tower is classified by:
a. How it produces air flow; mechanical or natural.
b. How the air flows in relation to the downward flow of water; cross or counter
current.
c. How the water flows in relation to the downward flow of air, cross or counter.
d. a & b
12. The temperature delta that exists between the water leaving the tower and the wet bulb
temperature of the air entering the tower.
a. wet bulb ÷ dry bulb
b. relative humidity ÷ dry bulb
c. approach to tower
d. temperature delta
13. A device used in a cooling tower to break up and redirect the flow of falling water.
a. louvers
b. drift eliminators
c. columns
d. splash bars
14. Vents located on the side of a cooling tower.
a. louvers
b. drift eliminators
c. columns
d. splash bars
15. Mechanical draft towers use fans to force air in (_______draft) or pull air out
(_________draft.)
a. forced draft and induced draft
b. induced draft and forced draft
c. cross and counterflow
d. counterflow and cross
16. Air moves through a (forced draft or induced draft) at a higher rate. What happens to the
flow rate at the discharge point?
a. forced, speeds-up, 10% efficiency increase
b. forced, slows-down, 20% efficiency decrease
c. induced, speeds-up, 10% efficiency increase
d. induced, slows-down, 20% efficiency decrease
17. The measure of how much water the air has absorbed at a given temperature.
a. humidity
b. wet bulb
c. relative humidity
d. dry bulb
18. Identify the following components.
18-1_______________ 18-2_______________ 18-3______________
18-4_______________ 18-5_______________ 18-6______________
18-7_______________ 18-8_______________ 18-9______________
18-10______________ 18-11______________
19. A term applied to fluid flow that is directed into one piece of equipment before exiting
and entering another. Example heat exchanger
a. parallel flow
b. series flow
c. cross flow
d. counter-current flow
20. A pipe that evenly disperses hot water over the fill of a cooling tower.
a. water distribution header
b. tower water discharge line
c. hot water inlet to cooling tower
d. a & c
21. Draw a simple hyperbolic cooling tower. Identify basic components.
22. Draw a simple induced-draft cooling tower with counter-flow.
23. A post used to support the framework of a cooling tower.
a. treated wood column
b. white pine column
c. plastic column
d. a & c
24. Hyperbolic towers are primarily designed for service in what industry?
a. chemical plants
b. power plants
c. refineries
d. fertilizer plants
25. A common term used to describe the internal buildup on the surface area of a heat
exchanger that results in restricted flow .
a. corrosion
b. plugging
c. fouling
d. scale
26. Draw a simple flow diagram of a cooling tower, pump, valves and three heat exchangers
in series service.
27. Draw a simple atmospheric cooling tower. Identify basic components.
28. Results when electrochemical reactions occur between metal surfaces and surrounding
hot water that results in the gradual wearing away of metal.
a. corrosion
b. plugging
c. fouling
d. scale
29. The result of dissolved solids adhering to internal surfaces of equipment in the form of
deposits.
a. scale
b. corrosion
c. fouling
d. plugging
30. Sensible heat transfer accounts for __________ to ___________ of the cooling effect in
a cooling tower.
a. 10% to 20%
b. 40% to 70%
c. 80% to 90%
d. 90% to 100%
31. Which tower is most efficient, forced or induced? What happens to the flow rate at the
discharge point?
a. forced, speeds-up, efficiency increase
b. forced, slows-down, efficiency decrease
c. induced, speeds-up, efficiency increase
d. induced, slows-down, efficiency decrease
32. The efficiency of a tower is tied to all of the following factors except:
a. relative humidity
b. temperature
c. wind velocity
d. personnel
e. equipment condition
f. tower design
g. water contamination
33. Hot water has all of the following characteristics except:
a. Hot water dissolves a little bit of everything it comes in contact with. By the time
the hot water returns to the tower it is full of suspended solids.
b. Hot water also has a tendency to become corrosive and deposit forming.
c. When hot water enters the cooling tower laced with suspended solids it undergoes
evaporation. This process removes water and leaves the solids. The remaining
fluid concentrates in the basin. Over time this concentration will build up to
levels that must be controlled.
d. Increases oxygen level in the water raising pH levels.
34. A term applied to fluid flow that is equally distributed to multiple pieces of equipment.
Example heat exchanger
a. parallel flow
b. series flow
c. cross flow
d. counter-current flow
35. ____________ draft cooling towers use natural forces to bring air into a cooling tower
while ____________ draft towers use fans to induce or force air into a tower.
a. natural & mechanical
b. cross and counter-current flow
c. vertical and horizontal
d. normal and modern
36. Which hyperbolic tower gets higher air flow; counter-flow, cross-flow?
a. counterflow
b. cross-flow
37. Which hyperbolic tower is more efficient; counter-flow, cross-flow?
a. counterflow
b. cross-flow
38. Evaporative cooling accounts for ___________ to __________ of the cooling effect in a
tower.
a. 10% to 20%
b. 40% to 70%
c. 80% to 90%
d. 90% to 100%
39. The rate of air flow in a natural draft cooling tower depends primarily on
_________________.
a. wind velocity
b. temperature
c. air intake louver position
d. a & b
40. Draw a simple flow diagram of a cooling tower, centrifugal pump, valves, and two heat
exchangers in parallel service.
Answer Key Chapter 8 Cooling Towers
