Objectives

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Objectives

• Control
• Multizone vs. Single system
• VAV vs. CAV
• Cooling towers

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Cooling towes

• Similarity and difference between
• Evaporative coolers and
• Cooing towers

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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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Cooling Tower
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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

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Summary

• Heat rejection is often accomplished with devices
  that have direct contact between air and water
• Evaporative cooling
• Can construct analysis of these devices
• Requires parameters which need to be measured for
  a specific system