That makes sense. I would think that assumes the control volume includes the entire system (A1 = area of tent, A2 = area of tube). Would conditions change if I am only looking at a small section of the larger "pipe" (roughly same cross-sectional area as tubing)?
I am designing a dust collection system for a powder mixing project. My current setup is basically a tent (roughly 6ft X 4ft X 7ft) with a dust collector tube hanging from the ceiling (or coming from the floor). I know the CFM, air properties, and pipe area at the end of the dust collector...