Refrigerant-134a enters the expansion valve of a refrigeration system at 130 psia as a saturated liquid and leaves at 20 psia. Determine the temperature and internal energy changes across the valve. Use data from the steam tables.

The answer is ""

Explanation:

Calculating the value from the property tables of R-134a,

At 130 psia:

Internal energy:

At 20 psia:

Internal energy

 Calculating temperature:

  Calculating  internal energy:

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