An ammonia refrigerating machine has working temperature of 35^ in the condenser and 15^ in evaporator. Calculate theoretical piston displacement, horsepower per ton refrigeration, and coefficient of

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4) An ammonia refrigerating machine has working temperature of $35^\circ\text{C}$ in the condenser and $15^\circ\text{C}$ in evaporator. Assume two cases: I. dry compression, and II. Wet compression. Calculate for each, the following (i) theoretical piston displacement per ton refrigeration (ii) theoretical horsepower per ton refrigeration, and (iii) the coefficient of performance.

Ammonia (R717) Properties (approximate values from tables):

• At Evaporator Temperature ($T_e = 15^\circ\text{C}$):
  • $P_e = 7.29 \text{ bar}$