kadem

Text Box

9.89

kadem

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9.90

kadem

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11.16

kadem

Text Box

Please note that there is an error in the calculation of the number of moles. The relation should be: N=m/M

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14-55

kg/min 439.9kg/s 1573.00.85

kJ/kg )48.25490.286(kW 6

1,2

==

−=

−=

R

R

C

RsRRC

m

m

hhmW

&

&

&&η

The rate of heat absorbed by the R-134a in the evaporator is

kJ/min 1.1042kJ/kg )07.14448.254(kg/min) 439.9()( 41in, =−=−= RRRR hhmQ &&

The rate of heat lost from the air in the evaporator is absorbed by the refrigerant-134a. That is,

outin, QQR&& = . Then, the volume flow rate of the air at the inlet of the evaporator can be determined from

Eq. (1) to be

/minm 44.87 3=⎯→⎯++= 1111 (33.63)002646.0(23.11)

0.84741.1042(43.05)

0.8474VV

VV &&&