The evaporative condenser of an ammonia refrigeration plant has a water flow rate of 100 kg/s and enters a natural draft cooling tower at 43 °C. The water is cooled to 30 °C by air entering at 27 oC db 24 °C wet bulb. The air leaves the tower as 90% RH and 32 °C db. Calculate the percent of make-up water needed the tower. At 27 °C db and 24 °C wb: h = 72.5 KJ/kg, w = 0.0178 At 90% RH and 32 °C db: h = 102 KJ/kg, w = 0.0275

The evaporative condenser of an ammonia refrigeration plant has a water flow rate of 100 kg/s and enters a natural draft cooling tower at 43 °C. The water is cooled to 30 °C by air entering at 27 oC db 24 °C wet bulb. The air leaves the tower as 90% RH and 32 °C db. Calculate the percent of make-up water needed the tower. At 27 °C db and 24 °C wb: h = 72.5 KJ/kg, w = 0.0178 At 90% RH and 32 °C db: h = 102 KJ/kg, w = 0.0275

Refrigeration and Air Conditioning Technology (MindTap Course List)

8th Edition

ISBN:9781305578296

Author:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson

Publisher:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson

Chapter3: Refrigeration And Refrigerants

Section: Chapter Questions

Problem 31RQ: Define a near-azeotropic refrigerant blend, and give twoexamples.

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