An annealing furnace is depicted in the Fig. P. 7.1 The fi re in the firebox acts as a gray plane,  = 0.7 at 1500°C, whereas the steel on the hearth acts as a gray plane,  = 0.8 at 800°C. The firebox...

An annealing furnace is depicted in the Fig. P. 7.1 The fi re in the firebox acts as a gray plane,
 = 0.7 at 1500°C, whereas the steel on the hearth acts as a gray plane,
 = 0.8 at 800°C. The firebox and hearth are separated by a bridgewall, and all other surfaces act as nonconducting and reradiating walls. Find the rate of heat transfer between the fi re and steel.