Example 2 An uninsulated steam pipe passes through a room in which the air and walls are at 25C. The outside diameter of the pipe is 70mm, and its surface temperature and emissivity are 200C and 0.8, respectively. Determine: a) What is the rate of heat loss by convection, if the coefficient associated with free convection heat transfer from the pipe surface to the air is 15W/m2-K? b) What is the rate of heat loss by radiation exchange with the walls?