1. HW2
Book problems:
8.5, 8.25, 8.27, 8.28, 8.22
 Additional Design Problem (#5):
Due October 7th

2. Objectives
Adiabatic cooling
Cooling towers
Cycles

3. Evaporative Cooling (air washing)

4. Air Washer Sprays liquid water into air stream
Typically, air leaves system at lower temperature and higher humidity than it enters

5. Evaporative Cooler

6. Air Washers/Evaporative Coolers
Heat and mass transfer is mutually compensating
Can evaluate based on temperature drop, humidification, or comparison to other energy exchangers

7. 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

9. Schematic

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