A drying oven consists of a long semicircular duct of diameter D = 1 m. Materials to be dried cover the base of the oven while the wall is maintained at 1200 K. What is the drying rate per unit length of the oven (kg/s ? m) if a water-coated layer of material is maintained at 325 K during the drying process? Blackbody behavior may be assumed for the water surface and the oven wall.

T- 1200 K T - 325 K - -D=I m D-1