Problem: a 600-foot-long round duct with a diameter of 12 inches delivers a 1000 CFM.
Given: 12 inches delivers a 1000 CFM; 1000 CFM coming through and it has 12 inch diameter and it has a length of 600 feet; 1...
Approach: So for this problem we have to use the friction loss chart.
Calc: So based on that we can come over here, go to 1000 CFM or on this line.
Calc: Okay 12 inches is the diameter, so that is coming on these diagonals.
Result: And that is 2.02 inches of water closest to answer choice C.
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Student questions asked in live office hours about this problem
OH 31: HVAC 12
Q: For Psychrometrics-12 (air washer problem), is the lever rule good enough to eyeball the ending state, and would it work for most similar problems?
A: For this specific problem the process was 100% effective toward the wet-bulb temperature, so the endpoint is well-defined and not ambiguous. The lever rule works for locating intermediate states on a process line, but I want you to actually draw this on the real psychrometric chart and tell me how it goes — then follow up with any questions.