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Vedmedyk [2.9K]

2 years ago

8

Air whose density is 0.082 lbm/ft3 enters the duct of an air-conditioning system at a volume flow rate of 450 ft3/min. If the di

ameter of the duct is 16 in, determine the velocity of the air at the duct inlet and the mass flow rate of air.

2 answers:

Akimi4 [234]2 years ago

4 0

Answer:

$Given:\\V_{flow} =450 ft^3/min\\P=0.082lbm/ft^3\\A=16In$

where P is density of air and v flow is volume flow rate, so in order to find velocity of air and mass flow rate formula is given by :

$M_{flow} =V_{flow} *P\\\\M_{flow} =450*0.082=36.9ib/min$

so velocity is:

$v=V_{flow} /A=339.03m/min$

ser-zykov [4K]2 years ago

3 0

Answer:

mass flow rate = 36.9 lb/min

v = 339.03 m/min

Explanation:

Use thermodynamic tables to find the density and entalpy of the air using the properties of temperature and pressure (2 psia and 77.3 ° F)

Density = 0.082 lbm / ft ^ 3

volume flow rate = 450 ft3/min

Calculate the mass flow by multiplying the flow by the density,

mass = volume × density

Mflow = 450 * 0.082

mass flow rate = 36.9 lb/min

v = Vflow/A

v = 339.03 m/min

v=339.03 m/min

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