HW Linde process is used for air liquefaction. The high-pressure gas leaving the compressor is at 120 bar and is cooled to 306 K (516 kJ/kg) before it is sent through the heat exchanger where it exchanges heat with low pressure gas leaving the separator at 2 bar. A 14 K approach is desired at the hot end of the exchanger so that the low-pressure gas leaving the exchanger is at 292 K (526 kJ/kg). Enthalpy of saturated liquid and saturated vapour at 2 bar are 121 kJ/kg and 314 kJ/kg, respectively. Determine: (a) The fraction of the air liquefied during expansion. (b) Temperature of the air on the high-pressure side of the throttle valve.

HW Linde process is used for air liquefaction. The high-pressure gas leaving the compressor is at 120 bar and is cooled to 306 K (516 kJ/kg) before it is sent through the heat exchanger where it exchanges heat with low pressure gas leaving the separator at 2 bar. A 14 K approach is desired at the hot end of the exchanger so that the low-pressure gas leaving the exchanger is at 292 K (526 kJ/kg). Enthalpy of saturated liquid and saturated vapour at 2 bar are 121 kJ/kg and 314 kJ/kg, respectively. Determine: (a) The fraction of the air liquefied during expansion. (b) Temperature of the air on the high-pressure side of the throttle valve.

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter10: Heat Exchangers

Section: Chapter Questions

Problem 10.17P

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