An ammonia refrigerator produces 30 tonnes of ice from ant at 0 °C in 24 hours. The temperature range of the compressor is 25 °C to -15 °C. The vapour is dry saturated at the end of compression. Assume a coefficient of performance to be 60% of the theoretical value. Calculate the power required to drive the compressor. Latent heat of ice = 135 kJ/kg. Properties of ammonia are as follows: Temperat ure Enthalpy (kJ/kg) Specific entropy (kJ/kg-K) (oC) Liquid Vapour (hf) (hg) Vapor (Sf) (Sg) Liquid 25 -15 298.90 1465.84 112.34 1426.54 1.1242 0.4572 5.0391 5.5490

An ammonia refrigerator produces 30 tonnes of ice from ant at 0 °C in 24 hours. The temperature range of the compressor is 25 °C to -15 °C. The vapour is dry saturated at the end of compression. Assume a coefficient of performance to be 60% of the theoretical value. Calculate the power required to drive the compressor. Latent heat of ice = 135 kJ/kg. Properties of ammonia are as follows: Temperat ure Enthalpy (kJ/kg) Specific entropy (kJ/kg-K) (oC) Liquid Vapour (hf) (hg) Vapor (Sf) (Sg) Liquid 25 -15 298.90 1465.84 112.34 1426.54 1.1242 0.4572 5.0391 5.5490

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.

Chapter6: Forced Convection Over Exterior Surfaces

Section: Chapter Questions

Problem 6.14P

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