I have noticed that some vacuum cleaners are rated in quot;Airwattsquot;. Now, if you multiply a volume flow rate by a pressure, you get units of kg.m2.s-3. Which are equivalent to Watts:Flow rate = m3.s-1Pressure = Pa = N/m2 = kg.m-1.s-2Product = kg.m2.s-3 = J.s-1 = W.So if you multiply the volume flow rate through a vacuum cleaner by the pressure change it creates, is that the rate at which work is being done to move air through the machine? Is this what quot;Airwattsmeans? And if you then divide this by the power being supplied to the motor, is this giving the efficiency of the machine?
I believe it is similar to mechanical horsepower, which takes into account both speed and torque. In the case of airwatts, it would be the available power to do work, taking into account both the pressure and volume of the airflow, outside of the vacuum motor's fan.
