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In an air-conditioning system, dry air flows over tubes carrying refrigerant R134a. The air is cooled...

In an air-conditioning system, dry air flows over tubes carrying refrigerant R134a. The air is cooled by transferring heat to the R134a; the air enters with a volume flow rate of 0.75 m3 s–1 at 305 K and 100 kPa, and it exits at 290 K and 95 kPa. The R134a enters at 4 bar in a vapor-liquid coexistence state with a quality of 20%; it exits at 4 bar and 30 °C. Ignoring heat transfer at the outer surface of the air conditioner, neglecting kinetic and potential energy changes, and assuming a steady state, determine a) the mass flow rate of R134a and b) the rate of heat transfer between the air and the R134a. Use the available tables, diagrams, and other reliable sources to obtain required thermodynamic data.

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Expert Solution

DEAR STUDENT, ANSWER MAY DIFFER DUE TO DIFFERENT VALUES OF THERMODYAMIC DATA AT DIFFERENT SOURCES. THANK YOU.


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