HW2

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HW2

• Book problems
• 8.5, 8.25, 8.27, 8.28, 8.22
•  Additional Design Problem (5)
• Due October 7th

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Objectives

• Adiabatic cooling
• Cooling towers
• Cycles

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Evaporative Cooling (air washing)
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Air Washer

• Sprays liquid water into air stream
• Typically, air leaves system at lower temperature
  and higher humidity than it enters

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Evaporative Cooler
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Air Washers/Evaporative Coolers

• Heat and mass transfer is mutually compensating
• Can evaluate based on temperature drop,
  humidification, or comparison to other energy
  exchangers

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Cooling Tower

• Similar to an evaporative cooler, but the purpose
  is often to cool water
• Widely used for heat rejection in HVAC systems
• Also used to reject industrial process heat

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Schematic
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Solution

• Can get from Stevens diagram (page 272)
• Can also be used to determine
• Minimum water temperature
• Volume of tower required