(5-7) A concrete wall is exposed to outside air at 2 °C and wind speed of 20 km/h. The wall consists of 250 mm concrete
Posted: Sat May 21, 2022 10:15 am
(5-7) A concrete wall is exposed to outside air at 2 °C and wind speed of 20 km/h. The wall consists of 250 mm concrete (p = 1,600kg/m) with 20 mm cement plaster (p = 1,800 kg/m') on the inside surface of the wall. The inside air temperature is 20 °C and its relative humidity is 40 %. The wall area is 15 m². Calculate the followings: (a) Heat transfer rate through the wall. (b) State if the moisture will condense on the inside wall surface or not. (c) The polystyrene board (p = 30 kg/m) thickness needed to reduce the overall heat transfer coefficient to 1.0 W/m².K.