Hi, I am stuck to a problem, in which I have to caculate heat loss in the system. Problem has a square channel of 9.5 cm x 9.5 cm with 3 mm thickness and 1 m in lengh. At 0.25u m a gauze is placed and heated. In this system heat is provided at only one location and is uniform across the cross-section. The temperature at the gauze is 573 k and tempearature of air outside is 300 k and inside the channel air is flowing. I am not able to calculate the heat loss since the heat is lost form the surface i have no profile for the variation of temperature of air inside channel and in this situation both conduction and convection are taking. Can someone give me the other way to loook on to this problem to calculate overall heat loss.