The walls of the refrigerated storage room are 10 m long and 3 m high and constructed with 120 mm (k = 0.935 W / [m ° C]) concrete blocks and 14 cm fiber insulation board (k = 0.048 W). / [m ° C])....

The walls of the refrigerated storage room are 10 m long and 3 m high and constructed with 120 mm (k = 0.935 W / [m ° C]) concrete blocks and 14 cm fiber insulation board (k = 0.048 W). / [m ° C]). The temperature of the cooling chamber is -10 ° C and the convective heat transfer coefficient is 40 W / (m² K); The outside air temperature is 30 ° C with a convection heat transfer coefficient of 10 W / (m² K). Calculate the overall heat transfer coefficient. Overall heat transfer coefficient =... W / (m² K).