Cubic Feet Per Minute
Cubic feet per minute (CFM) is an often confusing term because it has no single definition that applies to all instances. In the most basic sense, CFM means cubic feet per minute. Unfortunately, gases are compressible, which means that a figure in cubic feet per minute cannot be compared with another figure when it comes the mass of the gas. To further confuse the issue, a centrifugal fan is a constant CFM device or a constant volume device. This means that, provided the fan speed remains constant, a centrifugal fan will pump a constant volume of air. This is not the same as pumping a constant mass of air. Again, the fan will pump the same volume, though not mass, at any other air density. This means that the air velocity in a system is the same even though mass flow rate through the fan is not.
Read more about this topic: Standard Cubic Feet Per Minute
Famous quotes containing the words cubic, feet and/or minute:
“One of the great natural phenomena is the way in which a tube of toothpaste suddenly empties itself when it hears that you are planning a trip, so that when you come to pack it is just a twisted shell of its former self, with not even a cubic millimeter left to be squeezed out.”
—Robert Benchley (1889–1945)
“You show me a politician with his heels ten feet in the air, and by Judas priest, I’ll show you an honest politician.”
—Dalton Trumbo (1905–1976)
“A slight daily unconscious luxury is hardly ever wanting to the dwellers in civilisation; like the gentle air of a genial climate, it is a perpetual minute enjoyment.”
—Walter Bagehot (1826–1877)