Question

determine the actual power required to drive a compressor that delivers air at 150 scfm at 115 psig. the overall efficiency of the compresser is 72% . break down and explain . two number i dont understand . that is number 0.286 and last number -1 in last bracket thank very much i need to be able to read this

Answer 1

Data given → Q = 150 scom Pin = 14.69 psia Paut = 115psig = 129.69 psia Ncomp = 0.72 We know where 8=1.4 for air Work done by compressor on air=in Cp (T2 - T1) = in epti ( 72 - 7) = m Cp To ( 2 2 - 1) () - where Y=14 for air S = 1 4 - 1 = 0.286 warm opty(63) * -") Kdx kJ x K = KJ = Power min kok min. P.Q = KN mbak yon = Power Theoretical horsepower (HP) = PinQ [ / Pout 2 min 0286 65.4 65.4 Theoretical horsepower = 29.14 HP Actual horsepower - - theoretical = 29.14 ncomp 0.72 = 40.47 HP