Problem 5.7 For air-conditioning system operation in cold weather, it is possible to introduce enough outdoor air to eliminatecooling by the air conditioner. This is called an economizer, and the control strategy is to vary the amount of outdoor airentering a plenum so that the outlet state is at the set point. For zone conditions of 75 F and 50 % and a constant circulatingair flow rate of 25,000 cfm, determine the outdoor and return air flow rates necessary to maintain a 55 F supply air leavingthe plenum. The outdoor air temperature varies between 10 F and 50 F and the relative humidity is always 30 %. Drawsome conclusions from your results.

patm = 14.7 psia T1 = 75 F RH1 = 0.50 RH2 = 0.30 V3. = 25000 cfm Fraction =V2.V.3 T3 = 55 F

Answered: Problem 5.7 For air-conditioning system…

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter6: Forced Convection Over Exterior Surfaces

Section: Chapter Questions

Problem 6.8P

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