Mechanical Air Movement and Control

Question 1

How do we measure the volume of air passing through?

Answer 1

Cubic feet per minute (CFM)

Question 2

What does SP stand for

Answer 2

Fan static pressure

Question 3

K-Wheel blade

Answer 3

Blades cannot be adjusted.

Question 4

A-Wheel blade

Answer 4

Blades can be adjusted when fan is not operating.

Question 5

C-Wheel blade

Answer 5

Blades can be adjusted while fan is running

Question 6

The three types of Axial Flow Fans are:

Answer 6

-Propeller fans
-Tubeaxial fans.
-Vaneaxial fans.

Question 7

Which fan is the most used, can be found in industrial, commercia, institutional and residential applications and is often used indoors as an exhaust fan for general ventilation. (Axial Flow Fans)

Answer 7

Propeller Fan

Question 8

Which type of fan can handle large volume of air at a low static pressure, usually have little to no ductwork, and are mounted directly onto the wall? (Axial Flow Fans)

Answer 8

Propeller fans

Question 9

Which type of fans can be considered heavy duty propeller fans and are generally arranged for direct duct connection. (Axial Flow Fans)

Answer 9

Tubeaxial fans.

Question 10

All axial fans discharge air in a spiral motion, which produces high duct system losses due to excessive turbulence. (T/F) (Axial Flow Fans)

Answer 10

True

Question 11

Which type of fans is the most efficient and should be used whenever possible. (Axial Flow Fans)

Answer 11

Vaneaxial fans.

Question 12

Whats the main difference between the tubeaxial and vaneaxial fan. (Axial Flow Fans)

Answer 12

The Vaneaxial fan has guide vanes behind the wheel to improve efficiency by straightening the airflow.

Question 13

In centrifugal fans, the air leaves the impeller in a direction at right angles to the fan axis (T/F)

Answer 13

True

Question 14

Centrifugal fans can be sub-grouped or classified by their fan (wheel) Blade types (T/F)

Answer 14

True

Question 15

What are the 6 sub-group of centrifugal fans

Answer 15

1. Centrifugal fans with airfoil blades.
2. Centrifugal fans with Backward-Curved blades.
3. Centrifugal fans with Backward-Inclined Blades.
4. Centrifugal fans with Radial tip Blades.
5. Centrifugal fans with Forward-curved blades.
6. Centrifugal fans with Radial Blades.

Question 16

What are the 4 types of blades configuration. (Centrifugal fans)

Answer 16

1. Curved Blades.
2. Inclined Blades.
3. Airfoil Blades.
4. Radial Blades.

Question 17

What are centrifugal fans with forward curved blades best suited for ?

Answer 17

Application with higher airflow volumes volumes and pressures.
Airflow can be varied to match air distribution system requirements by making simple adjustments to the fan drive or control devices.

Question 18

Forward curved fans are common in wheel diameters up to. (Centrifugal fans)

Answer 18

24”

Question 19

Most up-flow residential heating equipment uses a centrifugal fan in what positional configuration.

Answer 19

CCWUBD
Counter-clockwise up blast discharge.

Question 20

A 1000 cfm of air is to be moved through a duct system with a total pressure of 0.4”wc. Which type of fan is best suited.

Answer 20

Forward Curved Blade Centrifugal Fan