Question

In an air-conditioned office, the dry bulb temperature of the supply air is 15°C. The state of air in the office has dry bulb temperature of 26°C and relative humidity of 52%. By using anemometer, it is measured that the flow rate of the recirculated air is 60.34 m3 /min. The HVAC system takes 18 m3 /min of outdoor air at 35°C and 55% relative humidity. The sensible heat ratio for the cooling coil is known to be 50%. Determine: (a) The latent cooling load of the office. (b) The minimum surface temperature of the office walls and windows in order to avoid condensation occurs on the walls and windows.

Answer 1

Date Page Soluhon Psoperthes al Redrulated aly Pel. humidity = z), How Tat 6σ.34 m' Proper Hes al fieshalr ->T: 35 RH SS7 How rale 182 Lcate both the pts Psychionnehic choit on. 7K5144 4o2- 0.019 thdHer -6.0 mybhit m2hy(m1m2)hs 60-34XS4 t (1&x 85)= C60.34 +18) xha Joln-4-2) =1.122 1s 10 ( 60.34 t16 xw3 60.34 X6.01)+(18x0.019 e al dA O.012

Ploting wa 61122 KS O 012 State polntom on ine (1-2) get we Psychrometric chart T3=30°c 2. hg- Eh122 ks/1s af dlA h4=atu alr enthalpy at 15 =42 ks 1gaf dA Sensible heat gain Now semsible heat Rah' gemsible heat + lakmthrat Sensible heat gain = Cha-h4) X e C60.34+18)XC GI122- 42 1498.017 ks/amin Puting Valu In aboue gquahon 1498.017 14 1498.617 +1atemt heat loac Tatimt heat load- 1498 017 Nous as the minimum tim p.al saturaton. af alr is in aboue case. sunlae e tem p. o coal. be comes less than 1'c. then condensahon may Ocear