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Problems & Applications: Calculate (determine) the following: 1. The absolute humidity of air which has 60% RH & Tdb = 25

oC:

[12.5g H2O/kg air]

2. The wet bulb temperature under these conditions: [19 oC]

3. The RH of air having a Twb = 15oC & Tdb = 30

oC: [18%]

4. The dew point of air cooled adiabatically from Tdb = 40oC & RH = 30%:

[25oC]

Application:

5. Calc. change in RH - To represent the changes taking place as air is heated prior to being blown over food:

a. Given: Incoming air quality: Twb 15oC; Tdb = 25

oC:

Required: % RH of incoming air: [RH1 = 34%]

b. Given: Heated air quality: Tdb = 50oC:

Required: %RH of heated air: [RH2 = 8.5%]

(Instructions: follow constant specific humidity line right to Tdb)

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