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In: Mechanical Engineering

Air enters a counterflow heat exchanger operating at steady state at 22°C, 0.1 MPa and exits...

Air enters a counterflow heat exchanger operating at steady state at 22°C, 0.1 MPa and exits at 7°C. Refrigerant 134a enters at 0.2 MPa, a quality of 0.33, and a mass flow rate of 30 kg/h. Refrigerant exits at 0°C. There is no significant change in pressure for either stream.

(a) For the Refrigerant 134a stream, determine the rate of heat transfer, in kJ/h
(b) For the refrigerant stream evaluate the change in flow exergy rate, in kJ/h.
(c) For the air stream evaluate the change in flow exergy rate, in kJ/h.


Let T0 = 22°C, p0 = 0.1 MPa, and ignore the effects of motion and gravity.
Round your answers to 3 significant digits.

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