Exercise 17.6Air at 20°C and 60% relative humidity is heated to 90°C and then enters acontinuous dryer in an adiabatic operation. The air exits at 40 °C. Calculate: a)the inlet volumetric flow rate of air required to remove 20 kg of water/h fromthe product and b) the required energy to heat the air. SolutionStep 1Draw the process diagram:mHeaterDryerH2H1WiVH1H2Step 2Find the properties of the air at the inlet using a psychrometric chart or thespreadsheet program Moist air properties.xls.Air at 20 °C dry bulb temperature and 60% relative humidity:Humidity WEnthalpy H1Humid volume VHI =%3DAir at 90°C dry bulb temperature and humidity W1:Enthalpy H2 =Air at 40 °C dry bulb temperature and enthalpy H2:Humidity W3Stęp 3Write a mass balance on the moisture between points 2 and 3:m. (W, - W)Substitute values and calculate ma:ma =Use the humid volume to calculate the volumetric flow rate:Step 4Write an enthalpy balance on the air between points 1 and 2 and calculate therequired energy:

Answered: Image /qna-images/answer/171b67de-6d90-4a90-9c5b-9293318c69bf.jpg

Exercise 17.6 Air at 20°C and 60% relative humidity is heated to 90°C and then enters a continuous dryer in an adiabatic operation. The air exits at 40 °C. Calculate: a) the inlet volumetric flow rate of air required to remove 20 kg of water/h from the product and b) the required energy to heat the air.

Exercise 17.6 Air at 20°C and 60% relative humidity is heated to 90°C and then enters a continuous dryer in an adiabatic operation. The air exits at 40 °C. Calculate: a) the inlet volumetric flow rate of air required to remove 20 kg of water/h from the product and b) the required energy to heat the air.

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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