Hey Ed, What Is Mass Flow?
In this edition of "Hey Ed", Ed discusses what mass flow is in Manual P.
Hey Ed, what is mass flow? Mass flow is a term used by the cool kids. There’s no other way to put it. Knowing mass flow, when you start to get it your chest puffs a little bit more, you stand a little taller. But in reality, mass flow is really nothing more than quantifying something in a more correct way. Generally, we talk about CFM (or cubic feet per minute) I like using the phrase that I stole from somebody a while back, called "chuckin' boxes". But the problem with using CFM in any kind of formulas to figure out any kind of BTU capacity is, when we heat the box it becomes less dense. When it becomes less dense it actually grows. So, when we want to correct for any kind of measurement, we can measure the air in pounds versus size and a pound will always be a pound. So, it’s a more correct measurement of that airflow and that’s the way I see it!
In this edition of “Hey Ed”, Ed discusses what mass flow is in Manual P.
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Ed Janowiak is the Manager of HVAC Design Education at ACCA.
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