Fan Laws #1 + Night 3

CFM2/CFM1=RPM2/RPM1

to solve for RPM2 if we rearrange the equation to?

• RPM2= CFM2/CFM1xRPM1

• RPM2= RPM1x(CFM1/CFM2)

• RPM2= RPM1xCFM2/CFM1

• RPM2= CFM2/CFM1/RPM1

True of False

CFM= Flow x Area

• True

• False

Velocity is the AVERAGE velocity in a test section of duct?

• True

• False

When we measure our duct work in inches we multiply by 144" to turn our area into feet?

• True

• False

Belt tension is critical and should ALWAYs be checked with a belt tension gauge!

• True

• False

2 Types of Misalignment are Angular and Parallel

• True

• False

What are the safest ways to measure the RPM of a shaft?

• Touching the shaft with a Tachometer to the shaft

• Putting a sticker on he shaft and using a photo Tachometer

• Using a Stroboscope

• Using a Tachometer with the wheel on it pressed against the belt

Total Pressure = Static Pressure + Frictional Resistance

• True

• False

The Abbreviation SCFM stands for: Standard Cubic Feet per Minute

• True

• False

Frictional Resistance of a duct system is indicated by:

• Velocity Pressure

• Static Pressure

• Total Pressure