0. Water is boiled at 1 x 105 Pa pressure in acoffee maker equipped with an immersion-type electric heating element. The coffeemaker initially contains 1 kg of water. Onceboiling started, it is observed that half of thewater in the coffee maker evaporated in18 minutes. If the heat loss from the coffeemaker is negligible, the power rating of theheating element is

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Engineering

Mechanical Engineering

er equipped c heating e lly contains

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

Chapter28: Special Refrigeration Applications

Section: Chapter Questions

Problem 2RQ

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Complete the following table for Refrigerant-134a. Use the data from the steam tables exactly as listed.
QUESTION 2 A new induced raft cooling tower is circulating 120 000 L/h of water that is cooled from 50 °C to 22 °C. How much blow-down and make-up is required to maintain the concentration of dissolved solids in the circulating water at four times the concentration in the make-up water? Assume the following: - The evaporated water contains no dissolved solids so all solids entering the system in the make-up must be removed by blow-down and windage. - The windage value of the induced draft cooling tower is 0.3% for each 5.6 °C. - The evaporative losses value is 1.1%.